Which statement is correct:

a) Batch operations allow the process to benefit from the Economy of Scale, but at the price of less flexibility

b) Separation is the heart of any chemical process, and the conceptual design starts from designing the separation units.

c) Inert is used to control the exotherms of the reaction.

d) Valuable species or species that are toxic and hazardous should not be purged, even in small concentrations.

e) c and d

Explain: Write 1 paragraph per question explaining the reasons to pick the correct answer and why you cannot pick the other options.