Green Chemistry Flashcards
(16 cards)
Prevention
It is better to prevent waste then to try and clean it up or treat it.
Atom Economy
Synthetic methods should be designed to maximise the use of of all materials used in the reactions.
Less Hazardous Chemical Syntheses
Synthetic methods should be designed to use and generate substances that possess little to no toxicity to human health and the environment.
Designing Safer Chemicals
Chemical products should be designed to exhibit little to no toxicity while achieving their desired function.
Safer Solvents and Auxilliaries
The use of auxiliary substances (e.g., solvents, separation
agents, etc.) should be made unnecessary wherever possible and innocuous when used
Design for Energy Efficiency
Energy requirements of chemical processes should be recognized for their environmental and economic impacts and should be minimized. If possible, synthetic methods should be conducted at ambient temperature and pressure.
Use of Renewable Feedstocks
A raw material or feedstock should be renewable rather than depleting whenever technically and economically practicable.
Reduce Derivatives
Unnecessary derivatization (use of blocking groups, protection/deprotection, and temporary modification of physical/chemical processes) should
be minimized or avoided if possible, because such steps require additional reagents and can
generate waste
Catalysis
Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.
Design for Degradation
Chemicals should be designed so at the end of their function they break down into innocuous degradation products and do not persist in the environment.
Real-time Analysis for Pollution Prevention
Analytical methodologies need to be further
developed to allow for real-time, in-process monitoring and control prior to the formation of hazardous substances.
Inherently Safer Chemistry for Accident Prevention
Substances and the form of a
substance used in a chemical process should be chosen to minimize the potential for chemical accidents, including releases, explosions, and fires.
What is atom economy?
(grams desired product/grams of all products and byproducts )multiplied by 100 to get a percentage.
Absorbance and Fluorescence Spectroscopy: Food Dyes and Roboflavin in Beverages
This experiment will introduce constructing calibration curves and determining unknown
concentrations from absorbance and fluorescence data. You will determine the concentration of
red and yellow food dyes both individually and in mixtures using absorbance spectroscopy. You
will also quantify the amount of riboflavin in a Rock Star energy drink using fluorescence
spectroscopy. This experiment is an example of using Inherently Safer Chemistry for Accident Prevention. Previous versions of this experiment used toxic metal ions in solution
instead of food dyes.
Computational and experimental investigation of pesticides
In this experiment you will analyze the toxicity of two common pesticides using both computational and experimental methods. You will examine many different properties of these pesticides including UV spectra, octanol-water partition coefficients, predictions of vibrational
modes, molecular orbitals, solvent accessible surface area and polarity, and molecule conformations. You will use some of these properties as guidelines for the potential toxicity of
the pesticides. You will then test the toxicity of the compounds through using data from an algae
ecotoxicity assay. Computational methods can Prevent waste by helping to identify which experiments might be fruitful to do before simply testing things out in the lab. In addition, this data from this experiment can be used to help predict if a compound will be toxic to aquatic life. This experiment also highlights the principles of Designing Safer Chemicals, Designing for Degradation, and Real-Time Analysis for Pollution Prevention.
Quantitative Gas Chromatography: Determination of D-Limonene in Orange Peel by a Liquid CO2 Extraction
You will extract orange oil from orange peels using liquid CO2 in this lab. Anisole is added as an internal standard. You will determine the amount of limonene in your samples using both internal standard and external standards. You will be asked to compare the two methods. The
use of greener solvents is discussed in the experiment because CO2 has been successfully used to
replace CH2Cl2 as extraction solvent. Methylene chloride is also replaced by ethyl acetate as the orange oil solvent prior to GC analysis. In addition to meeting the teaching objectives of analytical chemistry, this experiment serves to
introduce green chemistry principles. This experiment highlights Pollution Prevention, Energy
Efficiency, Renewable Feedstocks, Design for Degradation, and Safer Chemistry for accident prevention. Both the extraction and the analysis use Safer Solvents.
