Our environment needs to be protected from ever-increasing chemical pollution. Advances in science and technology can address the challenges of global environmental sustainability, which includes the release of persistent organic pollutants, climate change, and bioaccumulation of contaminants, endocrine disruption and ozone depletion. Achieving sustainability requires an intricate balance among resource use, economic growth and environmental impact. Green chemistry is a growing field of research where pollution is reduced by designing and developing chemical products/process addresses. Many of these are concerned by combining the critical elements of environmental improvement, economic competitiveness and social responsibility. In this chapter the scope for the development of green chemistry and the beneficial aspects have been discussed stressing future research.
Top1. Introduction
The chemical industry plays a key role in sustaining the world economy which accounts for 7% of global income, 9% of global trade, US$1.5 trillion in sales in 1998, with 80% of world output produced by 16 countries. Production is projected to increase 85% by 2020 compared to 1995 levels, roughly in pace with GDP growth, but at twice the per capita intensity (“OCED Environmental Outlook”, 2001). A 2003 winner, lipase catalysts for polymerizations, developed by Richard Gross of Polytechnic University, USA eliminates the need for protecting/deprotecting groups and solvents as well as enabling milder reaction conditions. More recently, the Montreal Protocol has led to the successful replacement of chlorofluorocarbons by compounds that do not affect the ozone layer appreciably and the Kyoto Protocol for lessening greenhouse gases is also getting wider endorsement. The risks posed by chemical processes have been minimized by limiting exposure, use, handling, treatment and disposal of chemicals. The existing legislative and regulatory framework that governs these processes focuses almost exclusively on this issue. By contrast, green chemistry seeks to minimize risk by minimizing hazard. It thereby shifts control from circumstantial to intrinsic factors, such as the design or selection of chemicals with reduced toxicity and of reaction pathways that eliminate by-products or ensure that they are benign. Such design reduces the ability to manifest hazard by providing inherent safety from accidents. Many industries, especially in developing countries, use technologies that are outmoded in terms of their environmental performance, inefficient in resource and energy use and ultimately, economically unsound when the social costs of pollution are accurately accounted for. Green chemistry offers a pathway by which the increased production of needed chemical goods and services can be achieved in a more materials-efficient, economically competitive, and environmentally benign manner. Green chemistry can potentially generate an even greater environmental benefit by removing the intrinsic hazard of particular products or processes, thereby moving them outside the scope of many environmental regulations. It is a major component of the science underlying the “responsible care” program of the chemical industry and of “sustainable development”. Making reduced hazard an important criterion for judging the performance of a product or process provides a new challenge for traditional academic research. Today, there is an increasing awareness that sophisticated technologies and radical new processes will be needed for the full potential for environmental improvement to be realized.
The term “green chemistry” was coined only 10 years ago. Given that the development time for a new chemical process is often more than a decade, there has been insufficient time for green chemistry principles to be translated systematically into industrial processes. Nevertheless, many recently developed processes and products fulfill most of the principles for green chemistry discussed later. For ex. the waste greenhouse gas, N2O from the manufacture of adipic acid (a component of nylon) is being reused as the oxidant in a greener route to phenol (Poliakoff, Fitzpatrick, Farren, Anastas, 2002).