Sustainable, efficient and safe processes through the use of flow and catalytic reactions
The use of flow reactions allows for better stoichiometry in reactions, which provides for greener chemistry. The use of catalysts, rather than stoichiometric reagents, is also one of the principles of green chemistry. These catalysts can be chemical or biological.
There is an increasing awareness of the impact chemical processes can have on the environment. The scientific and industrial community is reacting to these pressures by the use of sustainable and green chemistries. Flow processes are now being used to manufacture intermediates and pharmaceuticals.
Sustainable chemistry can be interpreted as the use of raw materials that can be renewed or recycled and incorporate the principles of green chemistry (1). The areas of interest for research and development are summarised in Table 1.
The twelve principles of green chemistry are shown in Table 2 (2).
The overall goals for new processes should, therefore, to be efficient and this has been called process intensification, where the goal is to perform a reaction at the limits of chemistry and physics, rather than at the limits imposed by the equipment used (3).
There are many ways to make a process green and more sustainable and many ways to assess the environmental impact. Some of the methods include E-factor (4), process mass intensification (PMI), atom economy and ECO+ (Figure 1) (5). A simple change of solvent can have a significant impact on environment ...