Are bio plastics green if there aren’t recipes for degrading the materials at the end of the cycle?
Think about it. We have answers to all the above questions. Just contact and ask us. Besides, there are twelve principles of green chemistry. These are found and detailed on page 30 of the book “Green Chemistry: Theory and Practice by Paul T. Anastas and John D. Warner (see reference below). These principles are described below with an explanation of what they mean.
PreventionPreventing waste is better than treating or cleaning it after it is formed. This is self-explanatory. Currently there is a whole industry built on cleaning waste. It is very expensive to treat waste and contain it. The waste has to be monitored even after it has been contained.
Atom EconomyWhen creating materials it is important to maximize the incorporation of all the materials used into the final product. In other words waste as little material as possible. For example, if the process has 50% atom economy, then half of the materials that are used turn out to be waste. Only half of the materials actually end up as product.
Less Hazardous SynthesisProcesses should be designed to use and generate substances that have little to no toxicity. Plan the process of creating the materials to use substances that are not toxic and to produce substances that are not toxic. This is often easier said than done!
Designing Safer ChemicalsChemical products should be designed to function well but while reducing toxicity. Reducing toxicity of the products reduces hazards to people and to the environment.
Safer SolventsWhenever possible avoid the use of additional substances such as solvents and separating agents. When these substances are needed they should be nontoxic substances.
Energy EfficiencyEnergy efficiency should be considered when designing and producing a product. The energy requirements should be minimized since they impact the environment and raise cost. When possible, processes should be conducted at room temperature and pressure.
Use Renewable ResourcesWhen possible the feedstock (or material used to make the product) should come from a renewable resources. For example, there is research being done to make chemicals out of products such as corn instead of coal or oil. Also, when choosing a feedstock look at waste from other reactions being made in the lab.
Reduce DerivativesDerivatives are chemicals which are used to cause a temporary effect in the process. This could be a chemical which protects a certain part of the substance that is later removed or it could be a chemical that causes a temporary change in a property so that a reaction can take place. Using derivatives should be avoided when possible. They do not end up in the final product and only increase waste, etc.
CatalysisUse selective catalytic reagents over stoichiometric reagents. A catalyst helps a reaction occur with less energy plus it speeds the reaction.
Consider the EndDesign for the proper disposal of the item. The product that is made should break down into nontoxic substances after it has been used. This way the product will not remain and buildup in the environment.
Use Real-time Pollution PreventionMethods need to be further developed to allow real-time monitoring of chemical processes. This includes monitoring while the process is happening, detection and control of the formation of hazardous substances, and monitoring after the substance has been disposed.
Accident PreventionThe substance and the form of the substance (liquid, gas, etc) should be carefully chosen to minimize accidents during the chemical process. Accidents include fire, explosion and accidental release.
Theory and Practice
paul T. Anastas and john C.
Publication Date – May 2000