Environmental and Green Chemistry

Environmental components (atmosphere, hydrosphere, lithosphere and biosphere)

 Atmospheric layers, vertical temperature profile, heat radiation budget of the earth. Temperature inversion.

Environmental pollution- Introduction, Pollutants- types & Classification.

 Effects and control of air pollutants: CO, NO_x, SO₂ and particulates.

Biogeochemical cycles of carbon, nitrogen and oxygen, Residence time.

Chemistry of water and chemical reactions in aquatic environment; concept of oxygen demand -DO, BOD, COD; TDS, pH, conductivity

Green house effect: Green house gases - Major sources and climate change, effect on global

warming and agriculture.

Acid Rain: Introduction; acid rain precursor, their aqueous and gas phase atmospheric oxidation reactions; damaging effects on aquatic life, plants, buildings and health; acid rain control strategies.

Ozone depletion: Ozone layer formation, reactions, role, and processes of ozone depletion.

Consequences of ozone depletion. Creation, non-catalytic and catalytic process of ozone destruction.

Aerosols, Smog formation

Introduction; threshold limiting value (TLV); Toxicity and control of Toxicants--

Non Metallic Compounds, Asbestos, Organic Compounds- POPs (phthalate, dioxins), PCBs, Pesticides, VOCs, endocrine disrupters, heavy metals-As, Hg, Cd, Pb.

History, Need and Goals. Green Chemistry and Sustainability and background of Green Chemistry.

Twelve Basic principles of Green Chemistry with their explanation and examples and special emphasis on the following:

Designing a Green Synthesis using these principles; Prevention of Waste/ byproducts; Atom Economy: maximum incorporation of the materials used in the process into the final products, calculation of atom economy of the rearrangement, addition, substitution and elimination reactions.

Prevention/ minimization of hazardous/ toxic products reducing toxicity.

Risk = (Function) hazard x exposure; waste or pollution prevention hierarchy.

Green solvents: Supercritical fluids, water as a solvent for organic reactions, ionic liquids, fluorous biphasic solvent, PEG, solventless processes, immobilized solvents and how to compare greenness of solvents.

Energy requirements for reactions: alternative sources of energy: Microwave assisted reactions in water: Hofmann Elimination, Hydrolysis (of benzyl chloride)

Ultrasound assisted reactions: Esterification, saponification, substitution reactions, Alkylations, oxidation, reduction, coupling reaction, Cannizaro reaction, Strecker synthesis, Reformatsky reaction.

Selection of starting materials; avoidance of unnecessary derivatization-careful use of blocking/protecting groups.

Use of catalytic reagents in preference to stoichiometric reagents; catalysis and green chemistry, comparison of heterogeneous and homogeneous catalysis, biocatalysis, asymmetric catalysis and photocatalysis.