A process is described for making renewable isobutene and renewable isoprene, comprising converting a mixed acid feed including acetic acid and propionic acid to a product mixture including isobutene and at least one or both of 2-methyl-1-butene and 2-methyl-2-butene in the presence of a catalyst, separating isobutene from the product mixture and dehydrogenating either or both of the 2-methyl-1-butene and 2-methyl-2-butene in the remainder to provide isoprene.