CDMtbe®/CDEtbe® Processes—Methyl Tertiary Butyl Ether (MTBE) or Ethyl Tertiary Butyl Ether (ETBE) is formed by the catalytic etherification of isobutylene with either methanol or ethanol. Both the CDMtbe and CDEtbe technologies are highly-flexible in processing various hydrocarbon feedstocks from the FCC/RFCC and/or steam cracker and dehydrogenation units to meet refinery or petrochemical requirements. These processes can also be used as pretreatment to produce high purity butene-1 because of their high isobutylene conversion (more than 99% which exceeds equilibrium limitations). The CDMtbe technology can also be integrated with Lummus Technology's CDIB® technology for the production of high purity isobutylene.