green chemistry milan sanader author, nelson chemistry
TRANSCRIPT
Green Chemistry
Milan SanaderAuthor,
Nelson Chemistry
GREEN CHEMISTRY INVOLVES…
• Reducing or eliminating the use or production of hazardous substances in the manufacture of chemical products
Considering the hazards of reagents as well as their properties
A GREEN CHEMICAL PROCESS IS
“benign by design”
Principles of Green Chemistry
Preventing pollution makes more sense that treating it
Less toxic reagents are safer
Use less solvents
Design for energy efficiency
Use Renewable Feedstocks
Design Safer Chemicals
Use catalysis rather than stoichiometric reagents
Improve atom economy% of atoms in raw materials
than make it into the final product
Less Hazardous Chemical Syntheses
Reduce Derivatives
Design for Degradation
Real-time analysis for Pollution Prevention
EXAMPLES OF GREEN CHEMISTRY
Safer dry cleaning
Replace chlorinated solvents like perchloroethylene (perc) with liquid carbon dioxide (CO2)
Reduction in solvent from 1300 L/kg to 7 L/kg
Elimination of the solvent dichloromethane, CH2Cl2
VIAGRA SYNTHESIS
IBUPROFEN SYNTHESIS
Boot’s synthesis 6 steps Atom economy: 40% (40% of atoms in raw
materials end up in product)
BHC synthesis 3 steps Catalysts Atom economy >90%
Battery Recycling
Tonolli Canada
Flash Smelting
Features:
Smelting occurs in an enriched oxygen atmosphere
Exothermic reactions fuel the smelter
Flash Smelting
Reduced fuel consumption Energy released fuels the reaction High yield of sulfur oxides – enough to
make the conversion to sulfuric acid economically feasible
Use of scrubbing is minimized or eliminated
Green Chemistry Is About...
Waste
Materials
Hazard
Environmental Impact
COST
Risk
Energy
Some Aspects of Green Chemistry
Catalysis
Process
Intensification
Separation
Processes
Energy
Efficiency
Solvent
Replacement
Safer Reactions
& Reagents
Use of
Renewable
Feedstocks
Waste
Minimisation
Green
Chemistry
IN SUMMARY,GREEN CHEMISTRY IS…
• Based on proven chemistry • Cost effective• More sustainable
= A “win-win” for business and the environment