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- Herausgeber: John Wiley & Sons
- Kategorie: Wissenschaft und neue Technologien
- Sprache: Englisch
This groundbreaking book offers an in-depth description of sustainable green catalytic processes that have emerged as the means to empower the existing protocols with greener, sustainable, and environmentally benign versions that hold enormous potential in industry and society.
Growing worldwide concerns about environmental pollution and global warming have directed the attention of scientists towards approaches for developing sustainable protocols, and the need for employing greener and more sustainable catalytic approaches that are environmentally greener and more eco-friendly than current ones. Green and sustainable catalysts are the one class of catalysts that possess higher selectivity and activity, efficient recovery from the reaction medium, recyclability, cost-effectiveness and are prepared using environmentally benign preparation techniques. The most potent instrument in organic synthesis, and the cornerstone of green chemistry, is catalysis which has broadened the possibilities for organic transformations in the direction of a sustainable future. The catalyst has been playing a vital role, from the improvement of reaction conditions to enhanced selectivity towards the intended product and a decrease in the creation of byproducts. The purpose of this book is to highlight the developments made towards designing new catalysts (homogeneous, heterogeneous, organocatalyst, nanocatalyst, photocatalyst, nanophotocatalyst, biocatalyst, nanobiocatalyst, metal catalyst etc,.) and present the advancements in the field of chemical synthesis using greener catalytic routes with far-reaching applications.
The other environmentally friendly method is the enzymatic synthesis of organic molecules, which substitutes safe reagents for those that imitate the biosynthetic route to synthesize the desired organic molecules. With its ability to produce transformations that occasionally enable the reduction of steps in a synthetic route, biophotocatalysis has long been recognized as a green technology and key to creating environmentally friendly and sustainable chemistry. The employment of sustainable green processes on the most crucial reaction steps of the synthetic protocol satisfies contemporary needs for environmentally friendly operations during the creation of valuable chemicals.
Readers will find the book:
- details new catalysts development designs (homo and heterogeneous);
- presents the advancement of organic synthesis using greener catalytic routes with far-reaching applications;
- elaborates on preparation techniques for green and sustainable catalysts that possess higher activity, efficient recovery, and cost-effectiveness;
- discusses how to epitomize a green approach towards the preparation of organic moieties via enzymatic synthesis;
- analyzes nano-catalysis with green-based reagents and solvents that allow producers to follow the fundamental pillars of the green economy;
- elucidates green chemistry’s principles and metrics of the chemical’s life cycle and design through disposal.
Audience
The core audiences for this book include scientists and engineers working in green chemistry, materials science, photocatalysts, biotechnology, nanotechnology, waste minimization, and sustainability. This book is an excellent resource for graduate students, R&D experts, and researchers in academic and industrial fields of chemical synthesis.
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Veröffentlichungsjahr: 2024
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Table of Contents
Cover
Table of Contents
Series Page
Title Page
Copyright Page
Preface
1 Green and Sustainable Catalytic Reaction Processes Including New Reaction Medium-Enriched Atom Utilization
1.1 Introduction
1.2 Background
1.3 Literature Review
1.4 Environmental Impact of Catalytic Reactions
1.5 Experimental Section
1.6 Results and Discussion
1.7 Summary and Outlook
References
2 Green Catalysis for Chemical Transformation: Need for the Sustainable Development
2.1 Introduction
2.2 Conclusion
References
3 Green Avenues in Controlled Radical Polymerization for Precision Synthesis of Macromolecules
3.1 Introduction
3.2 Green Advances in Atom Transfer Radical Polymerization Technique
3.3 Green Advances in Reversible Addition Fragmentation Chain Transfer Polymerization Technique
3.4 Green Advances in Nitroxide-Mediated Polymerization Technique
3.5 Conclusions and Future Perspective
References
4 Catalytic Synthesis and Application of Heterocyclic and Heteroatom Compounds: Recent Advances
4.1 Introduction
4.2 Conclusion
References
5 The Novel Trends in Asymmetric Catalysis: Green and Sustainable Catalysts
5.1 Introduction
5.2 Role of Green Synthesis and Catalyst
5.3 Asymmetric Hydrogenation Catalyzed by Transition Metals
5.4 Asymmetric Cross-Couplings Catalyzed by TM
5.5 Approaches to Profens Through Organocatalysis
5.6 Conclusions
Acknowledgments
References
6 Application of Nanocatalysts in Greener Synthesis of Chemical Compounds
6.1 Introduction
6.2 Green Strategies
6.3 Nanocatalysts for Green Synthesis of Organic Compounds
6.4 Conclusion
References
7 Heterogeneous Photocatalysis: Recent Advances and Applications
7.1 Introduction
7.2 Fundamental Principles of Photocatalysis
7.3 Photocatalytic Mechanisms
7.4 Factors Affecting Photocatalytic Efficiency
7.5 Recent Advances in Heterogeneous Photocatalysts
7.6 Applications of Heterogeneous Photocatalysis
7.7 Recent Advances in Enhancing Photocatalytic Performance
7.8 Prospects and Pioneering Challenges in Heterogeneous Photocatalysis
7.9 Conclusion
References
8 Role of Biocatalysis-Biotransformations in Sustainable Chemistry
8.1 Introduction
8.2 Principle of Biocatalysis
8.3 Recent Development in Biocatalysis
8.4 Future in Biocatalysis
8.5 Conclusion
Acknowledgments
References
9 Synthesis and Functionalization of Natural Products with Light-Driven Reactions
9.1 Introduction
9.2 Visible Light-Driven Total Synthesis of Natural Products
9.3 Visible Light-Driven Functionalization of Natural Products
9.4 Conclusion
Acknowledgements
References
10 Metrics of Green Chemistry and Sustainability
10.1 Green Metrics
10.2 Tools and Applications of Green Metrics
10.3 Life Cycle Assessment
10.4 Conclusions
References
11 Biocatalysis and Biobased Economy
11.1 Introduction of Biocatalysis and Biobased Economy
11.2 Carbon-Based Biocomposites
11.3 Waste Biomass
11.4 Enzymes as Catalytically Active
11.5 Immobilization of Enzymes in Biocatalysts
11.6 Biopolymer
11.7 Catalytic Applications in Biocatalysts
11.8 Computational Approaches in Biocatalyst
11.9 Conclusion and Future Prospects
References
12 Chemistry and Technology Innovation to Advance Green and Sustainable Chemistry
12.1 Introduction
12.2 Computational Chemistry Methods in Green and Sustainable Drug Design and Development
12.3 Green Chemistry Principles in Computational Drug Design
12.4 Case Studies in Green and Sustainable Drug Design Using Computational Approaches
12.5 Technology Innovations in Computational Green and Sustainable Drug Design
12.6 Challenges and Limitations in Computational Green and Sustainable Drug Design
12.7 Future Directions and Conclusion
References
13 Green Chemistry: The Emergence of a Transformative Framework
13.1 Introduction
13.2 Synthetic Routes with Catalysts in Stoichiometric Amounts with the Higher Selectivity of the Chemistry Showcasing Its Advancement
13.3 Solvent-Free Syntheses or Alternative Environmental Benign Solvents
13.4 Overcoming the Conventional Methods by Switching to Microwave, Ball Milling, and Photochemical Synthesis
13.5 Preventing the Usage of Toxic Chemicals, Use of Alternative Chemicals
Conclusion
References
14 Sustainable Therapeutic Approaches with Nanophotocatalyst
14.1 Introduction
14.2 Cancer Therapeutics
14.3 Photocatalysis and Drug Delivery
14.4 Challenges and Perspectives
14.5 Conclusion
References
15 Chemistry for Catalytic Conversion of Biomass/Waste Into Green Fuels
15.1 Introduction
15.2 Lignocellulosic Biomass
15.3 Conventional Approach for the Generation of Liquid Fuels From Lignocellulosic Biomass
15.4 Selective Transformations of Platform Chemicals
15.5 Conclusions and Future Perspectives
References
16 Detoxification of Industrial Wastewater by Catalytic (Photo/Bio/Nano) Techniques
Abbreviations
16.1 Introduction
16.2 Detoxification of Wastewater
16.3 Miscellaneous Types of Adsorbent
16.4 Adsorption Isotherm and Its Kinetics
16.5 Significance of Adsorption Technique for Remediation of Hazardous Effluents
16.6 Future Prospects of Detoxification of Wastewater Through Catalysis
16.7 Conclusion
References
17 New Trends in Asymmetric Catalysis: Chiral Hypervalent Iodine Compounds as Green and Sustainable Catalysts
17.1 Introduction
17.2 Role of Hypervalent Iodines in Asymmetric Synthetic Approach
17.3 Synthesis and Reactivity
17.4 Conclusion
References
18 High-Turnover Palladium Catalysts: Accelerating C-H Activation for Sustainable Green Catalysis
18.1 Introduction
18.2 High-TON Pd Catalysis for C-H Arylation of Arenes
18.3 Palladium-Catalyzed Activation of Csp
3
-H Bonds
18.4 Palladium-Catalyzed Cross-Dehydrogenative Coupling
18.5 Oxidative Alkynylation Reactions
18.6 Tandem C–H and N–H Activation
18.7 Conclusions
References
19 Thin-Film Fabrication Techniques in Dye-Sensitized Solar Cells for Energy Harvesting
19.1 Introduction
19.2 Structure and Operation Principle of DSSCs
19.3 Various Methods for Fabricating Thin Films for DSSCs
19.4 Concluding Remarks
References
Index
End User License Agreement
List of Tables
Chapter 1
Table 1.1 Comparison of deep eutectic solvents (DESs), supercritical fluids, a...
Table 1.2 Comparison of traditional catalytic processes with green, sustainabl...
Chapter 6
Table 6.1 Nanocatalysts for green synthesis of organic compounds.
Chapter 8
Table 8.1 Difference between catalysis and biocatalysis.
Table 8.2 Green chemistry and biocatalysis.
Chapter 10
Table 10.1 Mass-based metrics categorized as analogs of either E-factor or ato...
Table 10.2 E-factors for different chemical industries [6].
Table 10.3 Assigned penalty points for Eco-Scale calculation from Van Aken
et
...
Table 10.4 An example of Eco-Scale comparison of (1) reduction to nitrobenzene...
Table 10.5 Penalty points applied to calculate the final analytical Eco-Scale ...
Table 10.6 Most used metrics in the pharmaceutical industry [2, 28].
Chapter 19
Table 19.1 List of references for thin-film synthesis with magnetron sputterin...
Table 19.2 References using laser ablation or pulsed laser deposition techniqu...
Table 19.3 List of references used in thin-film fabrication by CBD technique f...
Table 19.4 List of references for thin-film fabrication by chemical vapor depo...
Table 19.5 List of references for thin-film fabrication by molecular beam epit...
Table 19.6 List of references for photoanode preparation by ALD technique for ...
Table 19.7 List of references for thin-film fabrication by thermal oxidation t...
Table 19.8 List of references for thin-film fabrication by SILAR technique for...
Table 19.9 List of references for dip coating (immersion) technique-based thin...
Table 19.10 List of references for thin-film fabrication by spin coating techn...
Table 19.11 List of references for thin-film fabrication by doctor blade techn...
Table 19.12 List of references for thin-film fabrication by solvothermal techn...
Table 19.13 List of references for thin-film fabrication by spray pyrolysis de...
Table 19.14 List of references for thin-film fabrication by sol-gel method for...
Table 19.15 List of references for thin-film fabrication by screen printing me...
Table 19.16 List of references for thin-film fabrication by ECD method for its...
Table 19.17 List of references for thin-film fabrication by electrospray depos...
List of Illustrations
Chapter 1
Figure 1.1 Environmentally friendly and sustainable catalytic reactions have s...
Figure 1.2 Novel reaction media include deep eutectic solvents, supercritical ...
Chapter 3
Figure 3.1 General reaction scheme showing the mechanism of conventional free-...
Figure 3.2 General reaction scheme representing atom transfer radical polymeri...
Figure 3.3 (a) Mechanism proposed for polymerization of 2-(methacryloyloxy) et...
Figure 3.4 Representation of general structures of RAFT agents and steps invol...
Figure 3.5 General reaction scheme of nitroxide-meditated polymerization techn...
Chapter 4
Figure 4.1 Schematic representation of the catalytic cycle showing photoredox ...
Chapter 5
Figure 5.1 Modern industrial era: green chemistry and enzymatic biocatalysis.
Figure 5.2 Enzymatic biocatalysis and the 12 principles of green chemistry are...
Figure 5.3 Compounds that have been created through substantial industrial app...
Figure 5.4 The common structure of (S)-profens.
Chapter 7
Figure 7.1 Multiple aspects of heterogeneous photocatalysis.
Figure 7.2 Mechanism for the generation of an electron-hole pair within a semi...
Figure 7.3 Illustration of different applications of heterogeneous photocataly...
Figure 7.4 Platinum loaded onto TiO
2
to increase active sites for charge trans...
Chapter 9
Figure 9.1 Few of the selective photocatalysts (PCs).
Figure 9.2 General photoredox cycle.
Chapter 10
Figure 10.1 The 12 principles of green analytical chemistry.
Figure 10.2 Metrics that can be employed in GAC.
Figure 10.3 NEMI pictogram. The field is filled with green, which means that t...
Figure 10.4 Modified NEMI pictogram. A three-degree scale for the greenness as...
Figure 10.5 Description of different pentagrams of the GAPI pictogram.
Figure 10.6 GAPI rules and criteria for assessing the analytical method.
Figure 10.7 Sample pictogram of AGREE tool in color scale.
Figure 10.8 Color scale for evaluation of green analytical chemistry using Eco...
Figure 10.9 Stages of an LCA according to EN ISO 14040 [35].
Chapter 12
Figure 12.1 Virtual screening process.
Figure 12.2 Molecular docking pose of a ligand into the binding cavity of the ...
Figure 12.3 Representation of molecular dynamics and simulation of targeted pr...
Figure 12.4 QSAR model generation.
Figure 12.5 Computational approaches in green chemistry.
Figure 12.6 Integrated green chemistry with modern computational techniques.
Figure 12.7 Challenges and limitations in computational green and sustainable ...
Chapter 13
Figure 13.1 Green chemistry: the emergence of a transformative framework.
Chapter 14
Figure 14.1 Carbonized hemin nanoparticle encapsulated in polymer for PDT to i...
Figure 14.2 Preparation of nanoenzyme OxgeMCC-r with single-layer Ru atom for ...
Figure 14.3 (a, b) The combined hole/hydrogen therapy protocol using nanocatal...
Figure 14.4 Synthesis of upconversion-Au/TiO
2
nanotubes (a). Controlled drug r...
Chapter 15
Figure 15.1 Classification of biofuels based on biomass feedstock.
Figure 15.2 Chemical structure of cellulose, hemicellulose, and lignin fractio...
Figure 15.3 Generation of biofuels from lignocellulosic biomass via thermochem...
Figure 15.4 Generation of bio-oils via pyrolysis of cellulose-based biomass.
Figure 15.5 Generation of bio-oils via pyrolysis from hemicellulose-based biom...
Figure 15.6 Generation of bio-oils via pyrolysis from lignin-based biomass.
Figure 15.7 Suggested cellulose depolymerization mechanism during organic solv...
Figure 15.8 Suggested conversion of D-xylose in the presence of supercritical ...
Figure 15.9 Decomposition of lignin proceeds through depolymerization.
Figure 15.10 Acidic hydrolysis of cellulose, hemicellulose, and lignin.
Figure 15.11 Generation of alkanes from sorbitol over metal and acid catalysts...
Figure 15.12 Suggested mechanism for hydrogen generation from glucose.
Figure 15.13 C–C coupling reactions of biomass-derived oxygenates over dual-be...
Figure 15.14 Schematic representation of the generation of biofuel from sugars...
Figure 15.15 Schematic representation of the two electrochemical routes involv...
Figure 15.16 Upgradation of HMF to biofuels.
Figure 15.17 Generation of levulinic acid from cellulose.
Figure 15.18 Different high value-added chemicals and fuels derived from levul...
Figure 15.19 Fundamental steps for the synthesis of GVL from levulinic acid.
Figure 15.20 Fundamental steps for the synthesis of GVL from furfural.
Figure 15.21 Chemicals and fuels obtained from GVL upgradation.
Chapter 16
Figure 16.1 Source of water pollution mainly groundwater and surface water pol...
Figure 16.2 Schematic representation of mechanism of photocatalysis.
Figure 16.3 Schematic representation of remediation of pollutants using bio-na...
Figure 16.4 Schematic representation of detoxification of wastewater by microb...
Figure 16.5 A schematic representation of clay nanocomposite used as an adsorb...
Chapter 17
Figure 17.1 Iodanes with iodine in +3 oxidation state.
Figure 17.2 Iodanes with iodine in +5 oxidation state.
Figure 17.3 First reported chiral hypervalent iodine(III) compounds.
Figure 17.4 (a, b) First reported hypervalent iodine(III) derivatives of amino...
Figure 17.5 Approaches to stereoselectivity.
Figure 17.6 Hypervalent iodine molecules with helical chirality.
Figure 17.7 Structure of hypervalent iodine presenting helical chirality.
Figure 17.8 Various reagents of chiral hypervalent iodine(III).
Figure 17.9 Various reagents of chiral hypervalent iodine(V).
Figure 17.10 Chiral iodoarene precursors.
Chapter 18
Figure 18.1 General mechanism of palladium-catalyzed C-H activation process.
Chapter 19
Figure 19.1 World electricity generation by different sources in 2018 [3].
Figure 19.2 Solar radiations on the Earth’s surface [13].
Figure 19.3 The diagram presenting working principles of a DSSC.
Figure 19.4 Brief classification of thin-film deposition techniques used in DS...
Figure 19.5 Schematic illustration of the apparatus, principle, and deposition...
Figure 19.6 Schematic illustration of DSSC with compact blocking layer to avoi...
Figure 19.7 Schematic representation of chemical vapor deposition experimental...
Figure 19.8 Basis of the SILAR method and its different steps.
Figure 19.9 Basis of dip coating method and its different steps.
Figure 19.10 Schematic representation of spin coating of the thin film with di...
Figure 19.11 Schematic representation of the doctor blade technique process fo...
Figure 19.12 A schematic diagram of the screen printing technique for thin-fil...
Figure 19.13 Schematic diagram of electrospray deposition techniques for the f...
Guide
Cover Page
Table of Contents
Series Page
Title Page
Copyright Page
Preface
Begin Reading
Index
WILEY END USER LICENSE AGREEMENT
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Scrivener Publishing100 Cummings Center, Suite 541JBeverly, MA 01915-6106
Publishers at ScrivenerMartin Scrivener ([email protected])Phillip Carmical ([email protected])
Sustainable Green Catalytic Processes
Edited by
Mousumi Sen
Department of Applied Chemistry, Amity University, Uttar Pradesh, Noida, India
This edition first published 2024 by John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, USA and Scrivener Publishing LLC, 100 Cummings Center, Suite 541J, Beverly, MA 01915, USA© 2024 Scrivener Publishing LLCFor more information about Scrivener publications please visit www.scrivenerpublishing.com.
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Library of Congress Cataloging-in-Publication Data
ISBN 978-1-394-21255-2
Cover image: Wikimedia CommonsCover design by Russell Richardson
Preface
This book offers a concise description of the application of catalysts for sustainable transformation of the environment in various essential aspects of science and technology. Sustainable green catalytic processes are emerging as the means to empower the existing protocols with a greener, sustainable, and environmentally benign versions that hold enormous potential in industry and academia. Growing international concerns about environmental pollution and global warming have directed the attention of scientists worldwide toward approaches for developing sustainable protocols, and the need for employing greener and more sustainable catalytic approaches that are environmentally greener and more eco-friendly than present ones. Green and sustainable catalysts possess higher selectivity and activity, efficient recovery from the reaction medium, recyclability, and cost-effectiveness, and are prepared using environmentally benign preparation techniques.
The most potent instrument in organic synthesis and the cornerstone of green chemistry is catalysis, which has broadened the possibilities for sustainable, organic transformations in future. The challenges associated with the application of synthetic transformations include the hazardous and cost inefficiency of reaction conditions. Green catalytic conditions, mostly dealing with utilization of safer driven chemical reactions, relax the processes in terms of ambiance and environment. Moreover, the application of photo- and biocatalytic reactions in organic synthesis has received a lot of hype in recent years, with the light-mediated access to bioactive and medicinal compounds along with natural products attracting the focus of the scientific world.
The application in drug derivatization and degradation has explicitly boosted the potency of photo- and biocatalytic processes. The concept of nano photocatalyst for drug-free therapeutics has added a new dimension to the process. The catalyst has played a vital role, from the improvement of reaction conditions to enhanced selectivity of products with a decrease in the creation of byproducts. However, all the catalytic approaches are not always greener. Some employ toxic metals that are not environmentally friendly and are difficult to recycle, which ultimately limits their application on an industrial scale.
The major challenge now is to frame a greener design and development process to create catalysts, and then to use those catalysts in chemical processes that are sustainable. Several catalysts are used in this, including, but not limited to, metal-catalysis, organometallic catalysis, electrocatalysis, photocatalysis, nanocatalysis, biocatalysis, homogeneous and heterogeneous catalysis, and others. Thus, this book highlights the developments made toward designing new catalysts and presents the advancements in the field of chemical synthesis using greener catalytic routes with far-reaching applications.
Chapter 1 focuses on the creation of ecologically friendly chemical processes that depend heavily on green and sustainable catalytic reactions. As the need to lessen the environmental impact of industrial activities becomes more widely acknowledged, catalysis offers a viable solution by permitting effective and selective transformations with less waste creation. The idea of an “atom economy” and the use of renewable feedstock help to further advance sustainability and lessen reliance on fossil fuels. These developments in green catalysis lay the groundwork for the creation of more effective chemical processes that are also cleaner, promoting a more sustainable future.
The second chapter describes various organic transformations that take place in water. Although significant advancements occur every day in the field of green chemistry, there is still much to discover. To attain a sustainable future, there is an urgent requirement to focus on the development of diverse, eco-friendly protocols, especially those which can be carried out in H2O. Enzyme catalysis needs to be explored extensively as well.
Chapter 3 is about the Reversible Addition-Fragmentation Chain Transfer (RAFT) polymerization, which operates through the reversible deactivation of radicals using special transfer agents. Photocatalysts in atom transfer radical polymerization (ATRP) have been found to mitigate downsides, such as biocidal UV light, low oxygen tolerance, and applicability to limited monomers.
The RAFT technique has been integrated with photooxidation/reduction catalytic reaction, where the modification has benefited in terms of low energy consumption, mild reaction condition, controllability, and high tolerance towards oxidation. Also note that while the inclusion of organic or inorganic photo redox catalysts to enhance the oxygen-tolerance of RAFT polymerization has been widely accepted, a metal-free approach has been additionally developed which is considered “greener”. Further, the sustainability of the RAFT polymerization technique has been improved by expanding its applicability to design bio-renewable plastics.
Chapter 4 evaluates new approaches like C-H bond activation, photoredox catalysis, borrowed hydrogen catalysis, selective (stereo- and regio-) syntheses, as well as other novel, inventive general protocols for the synthesis and functionalization of heterocyclic compounds that have greatly aided in drug discovery and pharmaceutical research. Therefore, this chapter provides an overview of several cutting-edge heterocyclic synthesis techniques currently used in the field of drug development and medicinal chemistry.
The study of asymmetric organo-catalysis is currently quite popular. Numerous appealing characteristics exist in it, including new forms of activation, gentle reaction conditions, and processes free of transition metals. These organo-catalysts more effectively uphold the sustainability and green chemistry principles. Asymmetric organocatalytic synthesis of enantioenriched profens has made amazing progress, although it has yet to reach its full potential. Thus, the fifth chapter discusses the future advancements in the synthesis of profens and how their derivatives are expected to significantly aid further research into innovative organo-catalyst systems that require reduced catalytic loadings.
Chapter 6 discusses the advancements made in recent years for the greener synthesis of chemical compounds using nanocatalysts. The chapter focuses on three major ideas that are considered important in the green synthesis of chemical compounds: (i) synthesis of green nanocatalysts; (ii) greener reaction conditions; and (iii) the use of green nanocatalyst along with greener reaction conditions.
The seventh chapter frames the recent advances in heterogeneous photocatalysis and its applications. It delves into the fundamental principles that underpin photocatalysis, encompassing a comprehensive examination of photocatalyst categories, the mechanisms governing photocatalysis, and the factors that influence its efficiency. Subsequently, this section explores the diverse applications of heterogeneous photocatalysis, spanning pollutant degradation, CO2 reduction, water splitting, and organic synthesis. The mechanisms and challenges associated with each application are discussed, along with recent advances in enhancing the photocatalytic performance of catalysts.
The chapter also presents the future directions and challenges in heterogeneous photocatalysis, which include the development of more efficient and stable catalysts, exploring new photocatalytic reactions, optimizing reaction conditions, and highlighting the importance of heterogeneous photocatalysis in addressing global environmental and energy challenges.
Briefly put, compared to traditional chemical processes, biocatalytic processes are more cost- and environmentally friendly, as well as sustainable. By applying the ideas of biochemistry, chemical science may solve the energy crisis, make industrial production infinitely more efficient, and provide mankind with wings.
Chapter 8 emphasizes the applications and improved properties of the nanostructures obtained using green synthesis, while Chapter 9 explores the mechanisms underlying the total synthesis and functionalization of natural products with light-driven reactions. This section explores the important phtoredox catalysis process, which is used extensively for the total synthesis of natural products of their functionalization. Because, the utility of natural products has been expanding their application in several fields like human and veterinary medicine, agriculture, the food and cosmetic industries, etc. The widespread application of visible-light-mediated photocatalysis is evolving as a new chemical tool for various C-C bond formation reactions.
Upcoming directions could include the increased use of these photocatalytic approaches due to its atom economical, green, and efficient characteristics. The introduction of “Green Metrics” has played a pivotal role, underscoring their critical contribution to advancing sustainable development. The tenth chapter introduces numerous metrics from across different fields, many have seen limited use for specific, one-time purposes.
Chapter 11 discusses the bio-based economy as the best approach to converting waste biomass, similar to how agricultural forestry by-products and food supply chain waste convert into liquid fuels, common chemicals, and biopolymers. Carbon-based nanocomposites are used as bio-catalysis, which are environmentally friendly.
Every technology’s success is determined by its accessibility of use and economic feasibility. This is the first evaluation of its sort to shed light on the energy and exergy evaluation of catalytic pyrolysis. As an alternative, exploration towards biocatalysts has begun because of their benefits, including milder reaction conditions, recyclability, selectivity, and biodegradability. Today, these changes could help bio-based chemistry by making it easier to develop helpful new ideas.
The goal of the twelfth chapter is to provide a brief overview of the various aspects of computational approaches, which provides a robust framework embedded with green chemistry. The development of extensive databases of chemical and environmental data can help to increase the precision of computational models and make it easier to create pharmaceutical products that are more environmentally friendly.
Chapter 13 highlights various green synthesis techniques and the principles of green chemistry that validate its power and potential to be highly beneficial to humans and the environment. The discipline of green chemistry has demonstrated that the innovation of thorough experts worldwide is producing an interesting and new chemistry that commands the drive of this transformation in theory and practice.
The fourteenth chapter presents various photocatalysts with high activity and functionality, better physicochemical stability, and superior biocompatibility, as well as potential applications in the bio-medical field. These compounds can also be used to manage biomedical waste. Various standard physicochemical techniques have been introduced to create nano-photocatalysts, but there may be impediments, such as the use of unsafe chemicals, arduous methods, expensive instruments, and time-consuming reactions. Furthermore, while researchers have explored the use of photocatalysts in drug delivery, their use in gene transport has not yet been well studied and requires further inquiry.
Chapter 15 concerns the sustainable development of a modern society that largely depends on the improvement of biorefinery platforms and green renewable fuels that reduce environmental pollution, as well as meet the global energy demand. This section explains how the chemistry behind the biofuel generation process will help design robust strategies for large-scale production of green fuels derived from biomass and waste for industrial applications.
The sixteenth chapter aims to detoxify industrial wastewater and reuse it through techniques like photo-, bio-, and nanocatalysts. The catalytic method is likely to be effective for treating drinking water and domestic and commercial wastes. Overall, this section projects a path of rapid development that provides a broad overview of recent applications of nanotechnologies and biotechnologies in wastewater treatment.
Chapter 17 presents a concise overview of several catalytic properties exhibited by hypervalent iodine (III/V). This section collates the reactions documented in the field of asymmetric hypervalent iodine chemistry, with a particular emphasis on the synthesis of chiral iodine (III and V) reagents or chiral iodoarenes, and explores the reactivity and proposed mechanisms of these reactions.
The eighteenth chapter sheds light on the significance of high-turnover palladium catalysts in the acceleration of C-H activation for sustainable green catalysis. The integration of efficient catalysts like palladium not only enables the synthesis of complex molecules but also reduces the environmental impact of chemical processes.
The last chapter broadly overviews the recent developments and novel applications of thin film fabrication techniques used in dye-sensitized solar cells (DSSCs) fabrication and discusses their advantages and challenges.
In conclusion, I am very grateful for all the hard work and effort made by the many contributors to this book. I thank all the authors for sharing their insightful research and information. I am particularly thankful to Aarushi Sen for her unending encouragement and support throughout the making of this book. Finally, I am most grateful to Martin Scrivener of Scrivener Publishing for his help and for making this book possible. I thank him for his patience and consistent support throughout the journey.
Dr. Mousumi SenJuly 2024
1Green and Sustainable Catalytic Reaction Processes Including New Reaction Medium-Enriched Atom Utilization
Amit and Mousumi Sen
Department of Chemistry, Amity Institute of Applied Sciences, Amity University, Uttar Pradesh, India
Abstract
The creation of ecologically friendly chemical processes depends heavily on green and sustainable catalytic reactions. As the need to lessen the environmental impact of industrial activities is becoming more widely acknowledged, catalysis offers a viable solution by permitting effective and selective transformations with less waste creation. With a special emphasis on the creation of novel reaction media and the enrichment of atom use, this abstract focuses on the essential elements of environmentally friendly and sustainable catalytic reactions. Since using a greener reaction medium can considerably increase the overall sustainability and efficiency of catalytic processes, it has attracted a lot of interest. These media, which have special features that enable increased selectivity, simpler separation, and less environmental impact, include ionic liquids, supercritical fluids, and water. To further reduce the usage of risky and volatile organic solvents and the total carbon footprint of the reaction, efforts have been made to design and develop alternative solvents or solvent-free systems. Ionic liquids have demonstrated significant potential as green reaction media due to their low vapor pressure, excellent thermal stability, and recyclable nature. They provide increased catalytic activity and selectivity while reducing the atmospheric release of volatile organic compounds (VOCs). Water, a plentiful and renewable solvent, has gained popularity as a desirable reaction medium for many catalytic processes. Its application decreases waste production and removes the need for hazardous and combustible organic solvents. The maximization of atom use is a fundamental component of environmentally friendly and sustainable catalytic reactions. Low atom efficiency in traditional catalytic processes frequently results in significant waste production. Recent developments, however, have concentrated on creating catalytic systems that enhance atom usage while minimizing waste generation. This can be done by creating catalysts with high selectivity, using cascade reactions to change several reactants at once, and coming up with methods to value-add waste streams or by-products. The overall effectiveness and sustainability of the reaction can be significantly increased by using catalysts that support high atom economy. Incorporating renewable feedstocks, such as molecules generated from biomass, also improves atom use and lessens reliance on fossil fuels. The idea of an “atom economy” and the use of renewable feedstocks help to further advance sustainability and lessen reliance on fossil fuels. These developments in green catalysis lay the groundwork for the creation of more effective chemical processes that are also cleaner, promoting a more sustainable future.
Keywords: Sustainable, catalytic, environmental, renewable, atom economy, selectivity
1.1 Introduction
A viable strategy for creating new chemicals and materials that adhere to environmental norms is using green and sustainable catalytic reactions. Three key components of an environmentally friendly and sustainable catalytic reaction process are the use of sustainable and renewable raw materials, the creation of effective catalytic systems, and the application of atom-efficient reactions. Additionally, generating long-lasting and effective catalytic reactions might greatly benefit from the creation of novel reaction media [1]. The process of green and sustainable catalytic reactions includes atom-efficient reactions as a key component. With little waste and great atom utilization, these processes utilize all or almost all of the atoms in the starting materials. With this method, there is less of a need for energy-intensive separation and purification procedures, which means less energy use and less negative environmental effects. Another crucial component of environmentally friendly and sustainable catalytic reactions is the utilization of renewable raw materials. Sustainable chemical and material production can be accomplished by using renewable raw materials like biomass and trash [2]. For catalytic reactions to be sustainable, efficient catalytic systems must also be developed. Effective catalytic systems can speed up reactions, use less catalyst, and increase product yields. To achieve sustainable and effective catalytic reactions, new reaction media such as ionic liquids (ILs), supercritical fluids, and deep eutectic solvents can also be crucial. These media can decrease waste production, increase energy efficiency, and enhance reaction selectivity [3]. The most prevalent solvent on Earth, water, has become a popular medium for environmentally friendly catalytic processes. Due to its low cost, non-toxicity, and inflammability, it demonstrates great green credentials. Different catalysts’ hydrophobicity and hydrophilicity can be adjusted to support specific aqueous medium reactions. Additionally, improved selectivity and reduced energy demands are frequently produced via water-mediated catalysis, thus boosting the sustainability of the process. Another prominent green reaction medium that has attracted interest recently is supercritical carbon dioxide (scCO2). Carbon dioxide transforms into a supercritical fluid with gas-like diffusivity and liquid-like density under particular pressure and temperature conditions. scCO2 is an eco-friendly substitute for conventional organic solvents, since it is nontoxic, nonflammable, and simple to recover after the reaction [4]. The family of solvents known as ionic liquids is made up only of ions. They are suitable for a variety of processes due to their low vapor pressure, good thermal stability, and excellent solubilizing qualities. By choosing various cations and anions, ILs can be customized to improve the solvation of reactants and catalysts, enabling cleaner and more effective catalytic processes. Due to their low cost, low toxicity, and ease of production, deep eutectic solvents (DESs) have become recognized as viable green reaction media. DESs are created by combining two or more components, often a hydrogen bond acceptor (such as urea) and a hydrogen bond donor (such as choline chloride). They are extremely adaptable as reaction media due to the specific interactions that result in the production of a eutectic mixture with properties different from those of its separate parts [5]. Numerous environmentally friendly catalytic reactions have been created as a result of the fusion of green catalysts and cutting-edge reaction media. Each of these illustrates the promise of green catalysis in diverse areas of organic synthesis, medicines, and materials research. They range from C-C and C-X bond formation, reduction and oxidation reactions, to multicomponent processes. In conclusion, resource conservation and environmental sustainability are two major worldwide concerns that need to be addressed. Green and sustainable catalytic reactions, with an emphasis on enhanced atom utilization in innovative reaction media, constitute a groundbreaking solution. Researchers and businesses alike may plow the way toward a greener and more affluent future where chemistry acts as a catalyst for change by leveraging the power of eco-friendly catalysts and cutting-edge solvents. The advancements and applications of particular green catalytic reactions will be covered in more detail in the sections that follow, with a focus on their revolutionary potential for creating a sustainable future [6].
1.2 Background
1.2.1 Traditional Catalytic Reactions
Traditional catalytic reactions are chemical processes that need a catalyst to speed up the process and/or modify the reaction’s selectivity. Catalytic reactions are more effective and economical ways to create compounds, since the catalyst is not used up in the reaction and may be reused [7]. The idea of catalysis has been around for centuries, ever since the first scientists noticed how particular compounds affected chemical reactions. However, important advancements in our understanding of catalysis did not occur until the late 18th and early 19th centuries. The groundwork for the creation of catalytic theory was built by scientists like Humphry Davy and Johann Wolfgang Döbereiner, who conducted groundbreaking research [8]. A typical illustration of a conventional catalytic reaction is hydrogenation. In this procedure, a metal catalyst made of platinum, palladium, or nickel is used to catalyze the reaction between hydrogen gas (H2) and unsaturated hydrocarbons such alkenes or alkynes. The catalyst makes it easier for the hydrocarbon’s double or triple bonds to break, allowing hydrogen atoms to combine with the carbon atoms to form saturated hydrocarbons. In order to improve the texture and stability of liquid vegetable oils, hydrogenation is frequently employed in the food industry to turn them into solid fats like margarine [9]. The traditional catalytic reaction known as oxidation, in which a material loses electrons or joins with oxygen, is another significant one. Transition metal catalysts like iron or manganese are frequently used to promote this reaction. For instance, the industrial manufacturing of nitric acid, a critical chemical used to make fertilizers, explosives, and other compounds, requires the oxidation of ammonia to produce nitric oxide (NO) and then nitrogen dioxide (NO2).
The Haber–Bosch process, which creates ammonia from nitrogen and hydrogen, is an illustration of a conventional catalytic reaction. Iron is used in this process as a catalyst, allowing the reaction to take place at lower temperatures and pressures than would otherwise be necessary [10].
The transformation of complicated hydrocarbons into useful products is a major function of catalysis in the petroleum industry. One noteworthy example is the catalytic cracking process, which converts big hydrocarbons from crude oil into smaller, more valuable hydrocarbons like petrol and diesel. In this procedure, zeolite catalysts are frequently used because of their great selectivity and stability. Traditional catalytic reactions are important for the industry, but they are also essential for environmental conservation. Vehicle catalytic converters transform dangerous exhaust gases like nitrogen oxides (NOx) and carbon monoxide (CO) into less dangerous substances like nitrogen, carbon dioxide, and water vapor using precious metals like platinum, palladium, and rhodium. Research into new catalyst materials and novel reaction routes is advancing quickly in the field of catalysis. In order to lower energy usage, waste production, and environmental effect, scientists are working to create more efficient and selective catalysts. Interdisciplinary research projects combining chemistry, physics, materials science, and engineering are responsible for this ongoing advancement. The efficient production of necessary chemicals, fuels, and minerals has been made possible by conventional catalytic reactions, which have altered industries and contemporary civilization. These processes have wide-ranging effects on numerous industries, ranging from catalytic cracking to ammonia synthesis and hydrogenation to oxidation. The future of humanity will be more sustainable and prosperous—thanks to the continued research and development in catalysis [11].
1.2.2 Significance of Green and Sustainable Catalytic Reactions
Due to growing worries about how human activity affects the environment, green and sustainable catalytic reactions are very important in today’s society [12]. The following are some of the main implications of environmentally friendly and sustainable catalytic reactions (Figure 1.1):
Figure 1.1 Environmentally friendly and sustainable catalytic reactions have several major ramifications.
Environmental Sustainability:
By using fewer harmful chemicals, producing less waste, and using less energy, green and sustainable catalytic reactions help to lessen their negative effects on the environment.
Resource Conservation:
By utilizing raw materials and renewable resources, these catalytic reactions lessen reliance on nonrenewable resources
[13]
.
Economic Advantages:
By lowering costs related to waste disposal and energy consumption, environmentally friendly and sustainable catalytic reactions can offer economic advantages. In the process of producing sustainable materials, they might also open up new economic prospects.
Benefits for Health:
By decreasing exposure to dangerous chemicals, these catalytic reactions help to lower the health risks connected to their use.
Innovation:
The development of new catalysts, reaction mechanisms, and process designs are encouraged by green and sustainable catalytic reactions, which can result in more effective and environmentally friendly chemical production
[14]
.
1.2.3 New Reaction Medium-Enriched Atom Utilization
In the area of environmentally friendly and sustainable catalytic reactions, substantial research is being done on the use of new reaction medium-enriched atoms. The effectiveness and viability of catalytic reactions can be significantly impacted by the use of innovative reaction media [15].
Deep eutectic solvents, supercritical fluids, and ionic liquids are a few examples of novel reaction media (Figure 1.2) that have recently been studied and compared (Table 1.1). These materials offer special qualities that can increase atom utilization, boost selectivity, and cut down on waste production [16].
1.2.4 Overview of Research Problem
Using enriched atoms and new reaction media, the research problem on green and sustainable catalytic reactions focuses on the environmental and sustainability issues raised by conventional catalytic processes [20]. The goal is to create and improve catalytic reactions that are more energy-, environmentally, and commercially feasible [21].
Figure 1.2 Novel reaction media include deep eutectic solvents, supercritical fluids, and ionic liquids.
Table 1.1 Comparison of deep eutectic solvents (DESs), supercritical fluids, and ionic liquids based on a few common criteria.
Reaction medium
State at standard conditions
Melting point
Applications
Reference
Deep eutectic solvents (DESs)
Liquid condition under ordinary pressure and room temperature
Possess reduced melting points
Utilized in electrochemistry, the extraction of metals from biomass, and pharmaceutical manufacturing
[17]
Supercritical fluids
Depending on the particular fluid and its critical temperature, a gaseous or liquid condition at standard pressure and temperature
Have no definite melting point
Used for medicinal purposes, essential oil extraction, and decaffeination
[18]
Ionic liquids
Liquid condition under ordinary pressure and room temperature
Melting points lower than 100°C
Used as lubricants, separation agents, electrolytes in batteries, and in electrochemistry and catalysis
[19]
Key elements of the research issue are as follows:
Environmental Impact:
Conventional catalytic processes frequently use solvents and reagents that are toxic or bad for the environment, which results in the production of hazardous waste and contamination. The goal of the research is to find and create greener reaction media with reduced or no negative environmental effects.
Energy Efficiency:
Finding methods to lower energy usage during the reaction processes is a key component of sustainable catalysis. This could involve researching renewable energy sources to power catalytic reactions or creating catalysts that can operate at lower temperatures
[22]
.
Atom Economy:
A key component of green catalysis is the use of enriched atoms. A reaction system’s overall efficiency is increased by making the most of its atoms in order to reduce waste production.
Catalyst Design:
The goal of the research is to develop new, effective, selective, and reusable catalysts. This will lessen the need for excessive catalyst dosages and prevent the usage of potentially dangerous substances.
Renewable Feedstocks:
Investigating the use of renewable feedstocks as the initial components in catalytic reactions promotes sustainability and lessens reliance on finite resources.
Green Chemistry Principles:
The study issue is in line with green chemistry’s guiding principles, which emphasize the value of waste minimization, ecologically friendly methods, and the use of safer chemicals
[23]
.
Interdisciplinary approaches incorporating knowledge from the fields of engineering, chemistry, and environmental sciences are necessary to meet these difficulties. By encouraging the use of green and sustainable catalytic processes in a variety of applications, the aim is to help the chemical industry become more environmentally friendly and sustainable [24].
1.3 Literature Review
1.3.1 Sustainable Catalysis
The creation and application of catalytic procedures that are socially, economically, and environmentally sound are referred to as sustainable catalysis. Utilizing catalysts that are nontoxic, regenerative, and effective at transforming raw materials into finished goods with high selectivity and yield constitutes sustainable catalysis [25]. With sustainable catalysis, the production of waste and the usage of dangerous chemicals are all reduced or eliminated. It also involves the utilization of renewable raw resources, such as biomass, and the creation of new catalytic processes that have a high atom economy, meaning that they employ a high percentage of the starting material to make the desired output [26]. The use of heterogeneous catalysts, which are easily removed from the reaction mixture and reused numerous times, is one of the important methods in sustainable catalysis. This reduces waste formation and boosts cost-effectiveness. High selectivity and yield can also be achieved using heterogeneous catalysts that are tuned to particular processes [27].
Overall, research on sustainable catalysis is crucial because it attempts to advance the creation of chemical processes that are more economically and environmentally sound. The production of chemicals and materials could be revolutionized through sustainable catalysis, creating a more sustainable future [28].
1.3.2 Green Catalytic Processes
Green catalytic reactions are those that are developed and put into use in a sustainable and environmentally beneficial manner. Green catalytic processes strive for excellent selectivity and yield while minimizing or eliminating the use of potentially harmful compounds, creating less waste, and consuming less energy [29].
There are a number of methods for creating green catalytic processes, such as the following:
Developing New Catalysts:
The development of novel catalysts that are more efficient and selective can lead to the generation of less waste and reduce energy usage. Natural minerals and other renewable resources can be used to make catalysts, which can help keep the process sustainable
[30]
.
Utilizing Renewable Raw Materials:
Utilizing sustainable raw materials that are renewable, such as biomass or garbage, might lessen the process’s negative effects on the environment
[31]
.
Using Nontoxic Solvents:
Using nontoxic solvents, including water or green solvents, can lessen the process’s negative effects on the environment and encourage sustainability.
Employing Heterogeneous Catalysis:
Less waste is produced and expenses are reduced when heterogeneous catalysis, which uses a solid catalyst, is easily removed from the reaction mixture
[32]
.
Developing Biocatalysts:
Enzymes are an example of a biocatalyst that may catalyze reactions under benign conditions, eliminating the need for harsh chemicals and fostering sustainability
[33]
.
1.3.3 Atom Utilization in Catalysis
The efficient use of atoms in a catalytic reaction to increase the yield of the desired product and reduce the creation of undesirable by-products is known as atom utilization in catalysis. Atom economics, which refers to the proportion of atoms from the beginning material that end up in the finished product, is closely related to the idea of atom utilization [34]. Effective atom utilization in catalysis is crucial for a number of reasons, including lowering the amount of waste produced during the reaction, utilizing fewer raw materials, and lessening the process’s negative effects on the environment. As a result of using atoms more effectively, less expensive reagents or catalysts are required, which can also result in cost savings [35].
Utilizing highly selective catalysts, which encourage the desired reaction pathway and minimize the creation of undesirable by-products, is one technique to increase atom utilization in catalysis. This can be accomplished by selecting the catalyst carefully, enhancing the circumstances of the reaction, and managing the stoichiometry of the reactants [36]. Utilizing catalysts made to function at low catalyst loadings is another technique to increase atom utilization during catalysis. High-activity catalysts that run at low loadings can improve reaction efficiency and lower waste production [37].
1.3.4 Reaction Medium for Green Catalysis
In green catalysis, the choice of reaction medium is crucial, since it has a big impact on the process’s overall effectiveness and sustainability. By utilizing safe and sustainable reaction media, green catalysis aims to reduce its negative effects on the environment and encourage environmentally friendly practices. This essay will examine some of the most popular reaction media used in green catalysis and how they help the chemical industry become more environmentally friendly and sustainable. Green catalysis is the use of catalysts and reaction conditions that limit the use of potentially dangerous solvents, limit the use of energy, and limit the production of trash. Therefore, for green catalysis, the choice of the reaction media is crucial [38].
Water, ethanol, isopropanol, and supercritical carbon dioxide are some of the most often used green solvents in green catalysis. Since it is so plentiful and safe for the environment, water is frequently utilized as a reaction medium in green catalysis. Water is an ideal solvent for high-temperature reactions because it is a polar solvent that can dissolve a wide variety of organic and inorganic compounds and has a high boiling point [39].
The reaction medium supercritical carbon dioxide is another one that shows promise for green catalysis. When carbon dioxide is exposed to particular temperature and pressure conditions, it transforms into the dense phase known as scCO2. It is a flexible solvent for numerous reactions, since it combines the characteristics of both gases and liquids. scCO2 is abundantly available from natural sources, nontoxic, and inflammable, making it safe for the environment. Its distinctive solvation capabilities make it possible to selectively extract some substances and can improve the catalytic activity and selectivity of some catalysts. Additionally, the separation of scCO2 from reaction by-products is simple, allowing catalyst renewal and streamlining the purification procedure. As a result, scCO2 has drawn attention as a sustainable and environmentally friendly substitute for conventional organic solvents. Ionic liquids have also shown promise as reaction media for environmentally friendly catalysis. Ionic liquids are molten salts made up of cations and anions; they are excellent for a variety of catalytic reactions due to their adjustable properties. They do not emit harmful fumes and are not combustible or volatile, and they frequently have very little vapor pressure. Ionic liquids have a wider range of applications, since they may dissolve a variety of substrates, including polar and nonpolar molecules. They can also stabilize catalysts and metal nanoparticles, making it simple to recover and recycle catalysts. Ionic liquids are used in green catalysis; however, their use may lead to questions regarding their biodegradability and potential toxicity. As a result, efforts are being undertaken to design and use more ecologically friendly ionic liquids. In some circumstances, the greenest method of preparing reaction media is solvent-free or solid-state catalysis. By removing the need for any liquid medium, solvent-free catalysis minimizes waste production and lowers the energy required for solvent recovery. On the other side, solid-state catalysis includes performing reactions on solid catalyst surfaces, enabling increased selectivity and recyclability. Both strategies boost atom utilization efficiency (AUE) while minimizing their negative effects on the environment, making them appealing choices for green catalysis [40–42]. In green catalysis, ethanol and isopropanol are frequently employed as environmentally friendly solvents. Both solvents are great choices for environmentally friendly reactions because they are both readily biodegradable and relatively nontoxic.
Overall, the type of reaction being performed, the characteristics of the catalyst, and the desired result all influence the choice of the reaction medium. But for green catalysis, water, ethanol, isopropanol, and supercritical carbon dioxide are all fantastic options [43].
1.4 Environmental Impact of Catalytic Reactions
Various industrial processes and chemical transformations depend heavily on catalytic reactions, but they can also have a big influence on the environment. Although catalysis can be more environmentally friendly than non-catalytic alternatives, it is important to be mindful of any possible environmental problems brought on by catalytic reactions [44]. Key environmental effects include the following:
Energy Requirement:
Energy input is frequently needed for catalytic reactions, particularly in processes that involve high temperatures and pressures. The energy source employed for these reactions may emit carbon, which would increase greenhouse gas emissions and the effects of climate change.
Production and Disposal of Catalysts:
The creation of catalysts can be an energy- and resource-intensive process. The creation of the catalyst may require mining, refining, and processing of raw materials, which might result in habitat loss, water pollution, and energy consumption, depending on the catalyst’s composition. In addition, if the used catalysts contain dangerous or poisonous components, their disposal may be problematic
[45]
.
Production of Waste:
Catalytic reactions can result in the production of waste products such as by-products, unreacted starting materials, and used catalysts. These wastes have the potential to pollute the environment and contaminate the air, water, and soil if improperly managed.
Toxicity and Pollution:
Some catalytic reactions may use hazardous compounds as catalysts or produce toxic by-products, which, if released into the environment, can be harmful to human health and ecosystems. Pollutants can have a negative impact on aquatic life, wildlife, and human populations by leaking into water bodies or entering the atmosphere.
Greenhouse Gas Emissions:
Some catalytic processes can result in the release of greenhouse gases, which fuels the warming and changing of the climate. For instance, the creation and usage of specific catalysts as well as the energy needed to power catalytic reactions could emit greenhouse gases like carbon dioxide
[46]
.
Water Use:
For cooling and processing, some catalytic reactions need a lot of water. Utilizing too much water can put a burden on the local water supply, especially in areas where there is a water shortage or a drought.
Land Use and Habitat Destruction:
The extraction of raw materials for the manufacture of catalysts and the construction of facilities for catalytic processes can result in land use changes and habitat destruction, which can have an impact on biodiversity and ecosystem balance.
Risk of Accidents:
Some catalytic reactions could include dangerous substances or high pressure, raising the possibility of mishaps or leaks that might endanger people on the job, nearby communities, and the environment
[47]
.
Researchers, businesses, and politicians are aggressively exploring sustainable catalysis methods to reduce these negative environmental effects. Green catalytic processes strive to use less energy, use less hazardous catalysts, increase atom efficiency, and provide environmentally friendly reaction media. Catalyst recycling and reuse can also cut down on resource use and waste production. The environmental impact of catalytic processes can be considerably decreased by using more environmentally friendly procedures and technology, which will help create a cleaner and more sustainable future [48].
1.4.1 Impact of Traditional Catalytic Reactions
The creation of materials, chemicals, and fuels, as well as other facets of contemporary civilization, has been significantly influenced by conventional catalytic processes. These responses have made it possible to produce goods in huge quantities effectively and affordably, which has helped the world economy expand [49]. Catalytic reactions have been essential in the manufacture of fuels, polymers, and other chemical compounds in the petrochemical industry. The subject of refining crude oil represents one of the most significant contributions. Heavy hydrocarbons have been transformed into lighter, more valued products like petrol and diesel using catalytic breaking and reforming techniques. This helps countries that are largely dependent on oil exports expand economically while also meeting the need for transport fuels on a worldwide scale [50]. Additionally, conventional catalytic processes have had a significant impact on the pharmaceutical sector. Catalysis is used to selectively and effectively produce a number of necessary pharmaceuticals and therapies. Palladium and platinum are two transition metal catalysts that have become essential instruments in the synthesis of pharmaceuticals because they allow for the precise assembly of complicated molecular structures. As a result, the creation of new medications has been accelerated, improving the choices for treating many disorders. It is impossible to ignore how classical catalytic processes affect the environment. The attempts to reduce waste and manage pollution have benefited greatly from these reactions. Catalytic converter application in automobile exhaust systems is one such instance. Before being released into the environment, these devices transform dangerous pollutants like nitrogen oxides and carbon monoxide into less dangerous ones. As a result, catalytic converters have considerably improved air quality and lessened the negative effects of vehicle emissions on the environment [51]
