By Timothy Solheim
The global interest in moving towards sustainable and environmentally friendly practices extends beyond the desire for renewable energy, but also applies to the development of green processes for chemical processes. The production processes for most pharmaceuticals are incredibly wasteful, with the generation of 50 kg of waste for 1 kg of pharmaceutical being very common with the industry. One reason these processes are incredibly wasteful is the style of the process, where each step in the process is performed in batches, with extensive purification between each step generating significant volumes of waste. One alternative to this style of processing is continuous flow, where chemicals are continuously fed through series of interconnected tubing, reducing the need for purification, leading to a greener, more environmentally procedure for creating pharmaceuticals.
Nanotechnology plays a role in this through the generation of tiny particles capable of accelerating chemical reactions, reducing the time and energy required for the reactions to occur. These nanoparticles come in a wide range of types, from particles made from gold and platinum, to tiny particles of sand or plastic coated with enzymes. In typical batch-by-batch processing, the removal of these particles is time consuming and generates a large waste stream, particularly because some of the particles can be harmful. This challenge of purification is less difficult for continuous flow processes where the nanoparticles can be attached to the inside of the tubing. Because the particles are attached to the tube, they never enter solution, and do not need to be removed through extensive purification. This also allows the reusability of the catalysts, again reducing the waste stream. The generation of these particles using nanotechnology contributes to the global goal of working towards green and sustainable practices.