Hydrocarbon processing apparatuses and processes for producing n-pentane and isobutane are provided herein. In an embodiment, a process for producing n-pentane and isobutane includes providing a hydrocarbon feed stream that includes C4 and C5 hydrocarbons. A recycle stream that includes C4+ hydrocarbons and the hydrocarbon feed stream is combined to produce a combined feed stream. The combined feed stream is separated to produce an iC4 product stream, an nC5+ product stream, and an iC5/nC4 feed stream. The iC5/nC4 feed stream is simultaneously disproportionated and isomerized in an isomerization zone to produce an intermediate stream that includes C3-C6 hydrocarbons. The C3-C6 hydrocarbons in the intermediate stream are separated to produce a C3− stream and the recycle stream that includes C4+ hydrocarbons.