Understanding Flow Chemistry
Flow chemistry is also known as plug flows or microchemistry. A flow chemistry is a chemical reaction run in a pipe or a tube. By pumping a reactive component together at a mixing junction and the flowing down a temperature controlled pipe or tube the microchemistry is achieved. The fluids in a pipe or a tube are moved in the pumps and where the tubes join one another fluids get into contact with each other. A flow reactor is a device in which chemical reactions take place in micro channels and thus are the apparatus where flow chemistry is achieved. Large companies in manufacturing can largely and effectively use flow chemistry.
Faster reactions offered by flow chemistry are some of its major advantages. Since flow reactors can be easily pressurized then this will allow the reactions to heated 100 to 150 degrees above normal boiling points thus creating reaction rates that are 1000 times faster, this whole process is known as super-heating. Secondly flow reactors enable excellent reaction selectivity thus ensuring cleaner products. Ultimate temperature control is achieved by rapid diffusion mixing which increases the surface area to volume ratio thus enabling instantaneous heating or cooling. Flow chemistry allows only a small amount of hazardous intermediate to be formed at any instant thus allowing excellent control of exotherms. concentration of chemical reagents and their volumetric ratio is the main focus for batch process while flow focuses on concentration of flow reagents and their ratio of their flow rate.
Reaction products existing in a flow reactor can flow into aqueous work up a system and this important since it allows it to be analyzed in line or by sampler or diluter. Plug flows offer rapid reaction optimization by enabling quick variations of reactions condition on a tiny scale which can be achieved with automation. Scale up issues is also minimized due to maintaining excellent mixing and heat transfer. Flow chemistry such as a five-second reaction at 250 degrees are enabled but are not possible in batch . Multistep procedure such as rapid, low-temperature deprotonation followed by instant addition of electrophile high temperature is made possible.
One of the biggest examples of flow chemistry is syrris. Other types of flow chemistry reactors are spinning disk reactors, spinning tube reactors, multicell flow reactors and oscillatory flow reactors. Variety of flow chemistry notes and reactions using flow chemistry systems are demonstrated by range of resources in syrris. However flow chemistry also has its drawbacks, the flow chemistry will require a dedicated equipment for precious continuous dosing. For the flow chemistry to be effective, the startup and shut up time of the process must be established.