The Benefits Of Green Chemistry PDF

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The Benefits Of Green Chemistry...

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The Benefits Of Green Chemistry As an inhabitant of the Earth, it is only natural to wonder what kind of effect we are having on our planet. Generally regarded as destructive and wasteful, our “footprint” as it is commonly referred to, points our world in the direction of exponential degeneration. The matter is not if, but when, we will exhaust our resources, and what can be done to reverse, or at least slow down the descent to our own demise. Things can be done on both the large and small scale to achieve such an end. Recent technological and scientific advancements have enabled scientists and engineers to protect and benefit the economy, people and the planet through implementation of Green Chemistry. The American Chemical Society Green Chemistry Institute describes green chemistry as a different perspective on how chemistry and chemical engineering should be done to reduce waste, conserve energy, and utilize replacements for hazardous substances. Through a series of twelve principles, the ideals of Green Chemistry attempt to lessen the negative effects scientific innovation and utilization tend to have on our environment (Pavia, et al 2007). The term “Green Chemistry” was coined by Paul Anastas and is comprised of twelve metrics, or principles, designed to decrease

waste and protect the environment. The first principle of green chemistry, prevention, describes the basic purpose of green chemistry, which is to protect the environment. The remaining principles of green chemistry include: atom economy, energy efficiency, catalysis, use of less harmful chemical syntheses, designing safer chemicals, solvents and auxiliaries, use of renewable feedstocks, reduction of derivatives, design for degradation, real-time analysis for pollution prevention, and inherently safer chemistry for accident preventions. All the aforementioned principles demonstrate an attempt to waste less energy and keep chemical interactions safe and controlled (Wardencki, et al 2015). The first metric, prevention, is an overall, generic principle which defines the greater purpose of green chemistry – that is to eliminate waste, protect the environment, and moderate hazards. “It is better to prevent waste than to treat or clean up waste after it has been created”. Treating waste can be a difficult as some reactions yield hazardous byproducts, byproducts which may require even more energy to dispose of safely and properly. By designing a process to create minimal to no waste, one does not have to worry about disposal of mass quantities of dangerous waste.

Second to prevention, atom economy is another principle of green chemistry. Akin to percent yield, atom economy compares the final mass of product with the final mass of all products, or reactants (Tobiszewski, et all 2015). According to the ideals of green chemistry, one should always strive for a high percent yield, and likewise should strive for optimal atom economy. In order to achieve the best yield, secondary reactions, additional catalysts, and/or environmental influences may be necessary to utilize all reactants for the production of a desired product. By doing a little research and adding a few steps to a reaction, one can greatly diminish the waste a reaction produces. Less popular among organic chemists is the practice of performing less hazardous chemical syntheses. This principle demonstrates how synthetic methods should be designed to generate substances that possess little to no toxicity to human health and the environment (Gupta, et al 2010). Not always practicable, toxic chemicals are still used by chemists because they are often thought of as the best option when trying to witness a particular reaction. Research into replacement chemicals still needs to be done, but until then, one should attempt to use less toxic materials in chemical reactions.

Another principle of green chemistry, energy efficiency is a principle which strives to utilize the least amount of energy possible to reach a desired outcome. Again, reduction of waste is a central theme. In this case, however, waste refers not to a physical manifestation resulting from a reaction, but a waste of energy resources. An example of such waste, Bunsen burners use energy which becomes lost in the ambient environment and therefore waste energy that is never used in a reaction. Following green chemistry, we must strive to utilize all resources in a reaction, and we must do so using the least amount of energy necessary to energize said reactions. Working hand-in-hand with energy efficiency, the utilization of catalysts helps decrease energy and time spent in a reaction. A catalyst is defined as “a substance that changes the velocity of a reaction without itself being changed in the process” (Gupta, et al 2010). Though unchanged in a reaction, the very presence of a catalyst speeds up the rate of reaction and results in full utilization of reactants involved in synthesis of a certain product. As energy input is diminished, the use of a catalyst results in less waste of energy, as well as less physical waste. Utilization of this principle has resulted in numerous advances in various fields, some of the most notable found

in the pharmaceutical industry. One objective of the pharmaceutical industry is to synthesize better drugs with less harmful side effects and that produce less toxic waste. Improvements to already existent compounds, made in cooperation with the principles of green chemistry, accomplishes such a goal. After developing a “greener” version of sitagliptin, the active ingredient in a drug for type 2 diabetes, the need for a metal catalyst was eliminated in favor of a biocatalyst. This process reduces toxic waste and improves yield and safety (Examples of Green Chemistry). All of the principles detailed in P.T Anastas and J.C Warner’s twelve principles of green chemistry should be given genuine consideration. Each principle is important in their own right and each contribute to the fundamental ideas of reduction of waste and protection of self and environment. As a college student, I have come to appreciate the third principle of green chemistry which is the utilization of catalysis. Having a catalyst presence in a reaction has saved me both time and energy and often resulted in a better yield. We should continue to use catalysts whenever possible in organic chemistry, and we should strive to understand their function in a reaction, as well as the benefits of their utilization....