How flow chemistry addresses the
12 Principles of Green Chemistry
Joe Socci and Sam Adams of Stoli Catalysts introduce the SABRe as an example of flow chemistry aiding in the greening of chemical production
In recent years , there has been a growing societal expectation that chemists and chemical engineers must do more to produce greener and more sustainable chemical processes . Customers are increasingly factoring sustainability into their purchasing decisions , including the sourcing of materials . As chemicals and their derivatives underpin the vast majority of consumer products , from detergents and plastics to batteries and drugs , chemical manufacturers clearly will be a key driver of the sustainable ( green ) revolution . When designing new processes or chemistries , a key tool in the chemist ’ s toolbox is the 12 Principles of Green Chemistry ( Figure 1 ), which Paul Anastas and John C . Warner developed in 1998 as a guiding framework to help achieve the goal of sustainability . Furthermore , the aim of green chemistry – “ to use chemical skills and knowledge to reduce or eliminate the use or generation of hazardous substances during the planning , manufacturing and application of chemicals in order to minimise threats to the health of operators and the environment ” - has been shown to be economically profitable . 1
Figure 1 – The 12 Principles of Green Chemistry
In the 1990s , green chemistry was established as a legitimate scientific field and the release of the EU ’ s Chemistry Council published the influential work , ‘ Chemistry for a Clean World ’, which enhanced the importance of ‘ greenness ’ for chemistry . In line with this , several process efficiency metrics were developed such as atom economy , the environmental impact factor ( E-factor ) and process mass intensity ( PMI ) to assess the environmental impact of chemical processes . Sheldon in 1992 defined the E-factor as : -
Mass of input materials ( kg ) - Mass of product ( kg ) - Mass of product ( kg )
Preventing waste
The first of the 12 Principles - the prevention of waste - considers the generation of any material that does not have realised value to be waste . This is often one of the simplest ways to determine the efficiency of the process . It can be done through
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