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Furthermore, biodegradable plastics are another area of application for green chemistry. Exploration of substitutes is necessary to decrease dependence on nonrenewable energy resources because of depleting fossil fuels, high costs of fossil oils, and environmental influences related to their byproducts (Giin-Yu, Chia-Lung, Ling, Liya, & Lin, 2014). Plastic substances that originate from petroleum chemicals have a harmful influence on the environment due to their non-biodegradable character (Getachew & Woldesenbet, 2016). Most plastic substances that are presently utilized in daily life are non-biodegradable polymers that are produced from fossil fuels (Dahman & Ugwu, 2014). Non-biodegradable plastics have an adverse impact on the environment, so different types of biodegradable plastics are being researched (2014). An alternative method to prevent plastic pollution generated through conventional fossil fuel-based plastics is the use of biodegradable plastics (Getachew & Woldesenbet, 2016). Poly(-β-hydroxybutyrate) (PHB) is an important biodegradable natural polymer that can be generated through zymosis procedures using various bacterial species, the majority of which have been proven to use PHB in their cells as the source of carbon and energy (Dahman & Ugwu, 2014). This makes PHB an ideal green biological material that can be produced from recycled low-cost materials using fermentative procedures (2014).
These principles of green chemistry have been used successfully in several aspects worldwide. Numerous consumers worry about their carbon footprint through the commodities they purchase, therefore, companies are regarding green chemistry as a tool to improve their market presence (Savage, 2013). However, there are plenty of barriers to green chemistry: for example, the entire green chemistry usage in the science group meets with remarkable difficulties that comprise economic, financial, regulatory, technical, organizational, and cultural barriers (Roschangar, Sheldon & Senanayake, 2015). Several companies have a serious resistance to the application of green chemistry due to a misconception that the development of green procedures is merely motivated by environment-friendly beliefs (Meyer, Gonzalez, Marteel‐Parrish, & Abraham, 2014). The main problem that engineers and chemists encounter is with regard to helping chemical industries increase their reliance on green chemistry (Meyer et al., 2014). An effective method would be to make stakeholders, such as investors and manufacturers, realize the advantages of using green chemistry in industries (2014). Looking to the future, the replacement of traditional chemical technologies by greener catalytic substitutes and the displacement of the noxious and/or harmful menstruums will continue to be significant, but needs to be supported by 2 more elements toward sustainability (Sheldon, 2017). First, the transition from a fossil fuel-based to a recycled biological-based processing of current chemical products and invention of new substances that are biological degradable (2017). Second, a shift from a discontinuous linear economy to a cyclical economy that devises substances and procedures with protection of resources and waste removal (2017). William Ford Jr pointed out that a good company produces wonderful services and products; however, a great company succeeds in all these things and makes an effort to develop a better world (2017).
In conclusion, the purpose of green chemistry is improving reaction design to minimize waste production, which has positive effects on the environment, the society, and the domain of chemical engineering. The principles of green chemistry give the chances to use eco-friendly methods and recycled materials to generate substances. There are many applications of the principles of green chemistry, such as green solvents, biological fuels and biodegradable plastics. Green chemistry has multiple advantages: firstly, safer processes can decrease the costs of toxic waste disposal. Secondly, green chemistry has advantages for workers and consumers, because it reduces exposure to harmful materials. However, there are some limitations to green chemistry: for instance, green menstruums are not always more useful than commonly used menstruums, so chemists and engineers try to find the solutions to decrease the limitations. In the future, green chemistry will still be a significant valuable part in manufacturing, as the loss of natural resources and the increasing serious environmental pollution. Green chemistry helps to develop the innovation of renewable energy, providing alternatives to fossil fuels and to a more economical use of resources.
Green chemistry is a new strategy for sustainable development of the chemical industry. The green carbon concept is the Foundation of science and as a new frontier science, it will become one of the mainstreams of chemical technology development in the 21st century. For the future development of green chemistry technology, the following aspects in researching and development should be paid attention.
(1) The direct conversion technology should be emphasised on and "atom-economy" for the synthetic steps should be improved. From a green point of view, many of the traditional organic synthesis requires two steps, or even three steps. It will reduce into one step as an atom-economic reaction and complete to direct conversion technology. This is the eternal theme for scientific workers. Such as the production of the propylene oxide, the traditionally method is by a two step reaction of chlorine by alcohol. With the development of titanium silicalite molecular sieve, you can achieve Catalysis oxidation of propylene to propylene oxide by atom-economy new method. Of course, to achieve the atom-economy with a single reaction is still very difficult, or even impossible, you can make full use of the relevant integration of chemical reactions, that is, the waste from a reaction as the raw material for another, so as to achieve the closed loop, realize the zero-emission of chemical production.
(2) Pay more attention to the input of the energy and energy management in the process. And develope technologies which will be with minimum energy consumption during the process cycle. Develop new processes and technologies for energy saving, instead of the traditional technologies with high energy consumption and carbon dioxide emissions. Rational use of solar energy, hydrogen energy and thermal energy to reduce carbon emissions in the process.
(3) The concentration conversion technologies of carbon dioxide in the output end is also paid attention to. Through the development of efficient catalytic material to address efficient activation and directional conversion of carbon dioxide and other key scientific issues. Also, it can promotion applications of renewable energy technologies with photocatalytic electrochemical methods in carbon dioxide, in pursuit of the minimum carbon dioxide emissions from the system.
In short, new developments, new requirements and new challenges in the chemical industry need to largely develop the green chemistry which is with low energy consumption, low carbon during the life cycle. To believe, with the improving of China chemical science and technology, the green and efficient chemical process will be gradually used in industria. The green chemistry will play a crucial role for the sustainable development of Chinese energy chemical industry and the environmental protection.
Sources
Ahluwalia, V. K., & Kidwai, M. (2004). Basic principles of green chemistry. In New Trends in Green Chemistry (pp. 5-14). Springer Netherlands.
Anastas, P., & Eghbali, N. (2010). Green chemistry: principles and practice. Chemical Society Reviews, 39(1), 301-312.
Chisti, Y. (2007). Biodiesel from microalgae. Biotechnology advances, 25(3), 294-306.
Dunn, P. J. (2012). The importance of green chemistry in process research and development. Chemical Society Reviews, 41(4), 1452-1461.
Dahman, Y., & Ugwu, C. U. (2014). Production of green biodegradable plastics of poly (3-hydroxybutyrate) from renewable resources of agricultural residues. Bioprocess and biosystems engineering, 37(8), 1561-1568.
Giin-Yu, A. T., Chia-Lung, C., Ling, L., Liya, G., & Lin, W. (2014). Start a research on biopolymer polyhydroxybutyrate (PHB). Polymers, 6, 706-54.
Getachew, A., & Woldesenbet, F. (2016). Production of biodegradable plastic by polyhydroxybutyrate (PHB) accumulating bacteria using low cost agricultural waste material. BMC Research Notes, 9(1), 509.
Gilbertson, L. M., Zimmerman, J. B., Plata, D. L., Hutchison, J. E., & Anastas, P. T. (2015). Designing nanomaterials to maximize performance and minimize undesirable implications guided by the Principles of Green Chemistry. Chemical Society Reviews, 44(16), 5758-5777.
Komarneni, S. (2003). Nanophase materials by hydrothermal, microwave-hydrothermal and microwave-solvothermal methods. CURRENT SCIENCE-BANGALORE-, 85(12), 1730-1734.
Mason, T. J., Cintas, P., Clark, J., & Macquarrie, D. (2002). Handbook of green chemistry and technology. Blackwell Science, Oxford, 372.
Meyer, D. E., Gonzalez, M. A., Marteel‐Parrish, A. E., & Abraham, M. A. (2014). The economics of green and sustainable chemistry. Green Chemistry and Engineering: A Pathway to Sustainability, 287-323.
Paul T.. Anastas, & Warner, J. C. (1998). Green Chemistry: Theory and Practice (pp. 25-59). New York: Oxford University Press.
Pfaltzgraff, L. A., & Clark, J. H. (2014). Green chemistry, biorefineries and second generation strategies for re-use of waste: An overview. Advances in Biorefineries: Biomass and Waste Supply Chain Exploitation, 1.
Roschangar, F., Sheldon, R. A., & Senanayake, C. H. (2015). Overcoming barriers to green chemistry in the pharmaceutical industry–the Green Aspiration Level™ concept. Green Chemistry, 17(2), 752-768. |
