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Estimation of environmental impact using the metrics discussed above can help identify the problems with an existing process or product. This can then help device targeted plans to find alternatives. Environmental impact assessment can also highlight future challenges, such as the need for technical developments in order to improve product quality for greener processes such that they can be competitive.

There are many ways to improve process sustainability, and most of them are based around finding alternatives to either the solvents used, the reactants used and/or the process conditions (e.g. temperature or pressure) [1]. Avoiding the use of solvents altogether is an excellent example of improving greenness of a process. Other alternatives include switching to solvents that are non-volatile organic compounds. The use of supercritical fluids (e.g. CO₂ and water) has also been reported as an alternative due to the ease of solvent separation and reuse. However, one should consider the energy required to operate processes under supercritical conditions (typically high temperatures and pressures; e.g. for water, the critical point is 374 °C and 220 bar). In the case of processes that require heating, alternative ways of providing energy, such as microwave or ultrasound, could be effective. These methods work on the principle of providing energy only to the desired location or chemicals without wasting energy by heating the entire medium or system.

Various ways of estimating the environmental impact, as discussed above, are powerful tools, however they require involvement and inputs from chemists and process engineers [7]. It is critically important to analyse how the modifications made to a section of a process can affect the entire process and perhaps beyond to the entire business. For example, environmental impact estimates cannot predict how changes in feedstock can affect the product value, profits and market competition due to feedstock availability. Answers to such questions can be obtained by performing techno-economic evaluation of a process [8].