Question

A chemical reactor gives a fractional conversion of only 10% of the expensive limiting reactant in the feed stream. Assuming nothing will improve the reactor’s performance, how would you design a process to make better use of the expensive reactant? What performance characteristics would you need for other process units? (b) A second reactor is available which gives 90% conversion but allows an irreversible, undesirable side reaction with only a 50% selectivity or the desired product versus the undesired product. For some cases, the 1st reactor would be better, while for others the 2nd reactor is a better choice. Explain what performance characteristics of other units would dictate this choice?

Answer 1

Step-by-step explanation:

A) install a SEPARATION unit on the output from the reactor and feed the unreacted reagents back to the reactor feed in a RECYCLE stream.

B) Even if one had a perfect separation unit, the 65% or reactant which went to undesirable side reaction is wasted. Recycle is not effective to help poor selectivity of the reactor.