Abstract
Modern trends in the greener synthesis and fabrication of inorganic, organic and coordination compounds, materials, nanomaterials, hybrids and nanocomposites are discussed. Green chemistry deals with synthesis procedures according to its classic 12 principles, contributing to the sustainability of chemical processes, energy savings, lesser toxicity of reagents and final products, lesser damage to the environment and human health, decreasing the risk of global overheating, and more rational use of natural resources and agricultural wastes. Greener techniques have been applied to synthesize both well-known chemical compounds by more sustainable routes and completely new materials. A range of nanosized materials and composites can be produced by greener routes, including nanoparticles of metals, non-metals, their oxides and salts, aerogels or quantum dots. At the same time, such classic materials as cement, ceramics, adsorbents, polymers, bioplastics and biocomposites can be improved or obtained by cleaner processes. Several non-contaminating physical methods, such as microwave heating, ultrasound-assisted and hydrothermal processes or ball milling, frequently in combination with the use of natural precursors, are of major importance in the greener synthesis, as well as solventless and biosynthesis techniques. Non-hazardous solvents including ionic liquids, use of plant extracts, fungi, yeasts, bacteria and viruses are also discussed in relation with materials fabrication. Availability, necessity and profitability of scaling up green processes are discussed.
Highlights
The term Green chemistry, offered to the scientific community in 1991 was designed for elimination or decrease in hazardous substances, trying to reduce the exposure of humans and environment to chemicals
A recent review on photocatalysis [27] describes generation of singlet oxygen and its role in the photo-oxygenation, combination of photochemical processes with enzyme catalysis, application of continuous flows or microreactors for their optimization. Some examples of such reactions are the synthesis of N-containing heterocycles by photo-oxidation of furan derivatives, asymmetric oxidations catalysed with enzymes, and preparation of several F-organic compounds by photocatalysed trifluoromethylation of aromatics, using photocatalysis booth and reactors described in [28]
The synthesis assisted with magnetic fields has numerous advantages due to its simplicity; it has some important limitations, derived from the foundation of the technique, because it can only be applied to materials whose reactants or products have magnetic properties; that is why the vast majority of reports in the literature use magnetic iron oxides
Summary
The term Green chemistry, offered to the scientific community in 1991 was designed for elimination or decrease in hazardous substances, trying to reduce the exposure of humans and environment to chemicals. — lower-hazard chemical reactions using little-toxic and safe chemical substances; — low-toxic and safe separation agents and solvents (water, natural compounds as, for example, plant extracts); — minimization of energy consumed ( preferable/ideal conditions: normal pressure and room temperature); — renewable sources (raw materials); — minimization of reagents to avoid unnecessary wastes (lesser number of reaction steps and additional chemicals); — use of most selective catalysts, allowing higher yields of reaction products; — degradable reaction products, non-persisting in the environment; — contamination prevention via permanent (real-time) analysis of reaction intermediates when possible; — small quantities of reactants to prevent accidents (explosions, releases, fire); — green processes are cheaper and cost-effective, frequently resulting in products with a better quality; and — green reactions allow avoiding problems with many environmental regulations and laws. We will discuss below the green synthesis of organic and coordination compounds, macro- and nanosized objects
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
