A process for the production of high purity isobutylene, comprising: supplying a mixed C4 feed stream, comprising isobutylene, isobutane, and 1-butene, and optionally comprising one or more of butadiene, 2-butene, or n-butanes, to a catalytic distillation column containing a butene isomerization catalyst; in the catalytic distillation column, concurrently isomerizing 1-butene to 2-butene and separating the 2-butene from the isobutane and isobutylene; recovering the 2-butene from the catalytic distillation column as a bottoms stream; recovering an overheads fraction comprising the isobutane and isobutylene from the catalytic distillation column; condensing the overheads fraction comprising the isobutane and isobutylene in an overheads system; feeding at least a portion of the condensed overheads fraction to a splitter and separating the isobutane from the isobutylene in the splitter; recovering a bottoms stream from the splitter comprising the isobutylene; and recovering an overheads stream from the splitter comprising the isobutane; wherein the process further comprises: operating the catalytic distillation column at a pressure in the range of 0.5 MPaa to 2 MPaa (5 bara to 20 bara) and at an overheads temperature greater than a bottoms temperature of the splitter, wherein the overheads temperature is in the range from 42°C to 138°C; and heating a portion of the splitter bottoms stream via indirect heat exchange with at least a portion of the catalytic distillation column overheads fraction, producing a heated bottoms stream fed to a lower portion of the splitter and a cooled overheads fraction; and feeding the cooled overheads stream via at least one flow line to the overheads system. supplying a mixed C4 feed stream, comprising isobutylene, isobutane, and 1-butene, and optionally comprising one or more of butadiene, 2-butene, or n-butanes, to a catalytic distillation column containing a butene isomerization catalyst; in the catalytic distillation column, concurrently isomerizing 1-butene to 2-butene and separating the 2-butene from the isobutane and isobutylene; recovering the 2-butene from the catalytic distillation column as a bottoms stream; recovering an overheads fraction comprising the isobutane and isobutylene from the catalytic distillation column; condensing the overheads fraction comprising the isobutane and isobutylene in an overheads system; feeding at least a portion of the condensed overheads fraction to a splitter and separating the isobutane from the isobutylene in the splitter; recovering a bottoms stream from the splitter comprising the isobutylene; and recovering an overheads stream from the splitter comprising the isobutane; wherein the process further comprises: operating the catalytic distillation column at a pressure in the range of 0.5 MPaa to 2 MPaa (5 bara to 20 bara) and at an overheads temperature greater than a bottoms temperature of the splitter, wherein the overheads temperature is in the range from 42°C to 138°C; and heating a portion of the splitter bottoms stream via indirect heat exchange with at least a portion of the catalytic distillation column overheads fraction, producing a heated bottoms stream fed to a lower portion of the splitter and a cooled overheads fraction; and feeding the cooled overheads stream via at least one flow line to the overheads system. operating the catalytic distillation column at a pressure in the range of 0.5 MPaa to 2 MPaa (5 bara to 20 bara) and at an overheads temperature greater than a bottoms temperature of the splitter, wherein the overheads temperature is in the range from 42°C to 138°C; and heating a portion of the splitter bottoms stream via indirect heat exchange with at least a portion of the catalytic distillation column overheads fraction, producing a heated bottoms stream fed to a lower portion of the splitter and a cooled overheads fraction; and feeding the cooled overheads stream via at least one flow line to the overheads system.