There is a raw material that we can consider as a pure molecule $A.$ In a chemical reactor, this molecule $A$

can be transformed into $B($which is the desired product$)$ or into $C,$ which is the residual product. The first

reaction is irreversible second$-$order and the second one is reversible first$-$order. From both a productivity

and environmental standpoint, discuss the following alternatives:

a$.$ Using a plug flow reactor or a continuous stirred tank reactor.

b$.$ Incorporating a device inside the reactor that allows for continuous separation of B $($for example, a

selective membrane for B$).$

c$.$ Directing the reactor outlet stream to a separation operation that selectively separates $C$ and recycles it

back to the reactor.