Catalytic processes for light olefin production

Abstract

Up to now, the major process for light olefin production has been thermal steam cracking. The diversification of feedstocks from heavy oil fractions to light hydrocarbons as well as methanol led to the development of catalytic processes. Differing from the radical mechanism for olefin formation by the thermal process, there are two reaction mechanisms for the description of olefin formation in the catalytic process: the carbocation mechanism for hydrocarbon cracking and the hydrocarbon pool mechanism for methanol to light olefin. Deep catalytic cracking (DCC), developed by the Research Institute of Petroleum Processing (RIPP) of Sinopec, is a fluidized catalytic cracking process that uses a proprietary catalyst for the selective cracking of a wide variety of heavy feedstocks to produce light olefins. The catalytic pyrolysis process (CPP), also developed by RIPP of Sinopec, is an extension of DCC that gives an increased ethylene yield while keeping propylene production at a reasonable rate. The commercial units run worldwide showing the success of the development of these processes. The key process features, the representative catalysts, and the performance of PetroFCC, Propy-lur, SuperFLEX, propylene catalytic cracking, olefins catalytic cracking, olefin sconversio ntechnology, propane dehydrogenation, and methanol-to-olefins are also briefly introduced. In future, for the production of light olefin, catalytic processing is the key step to integrate the refining and petrochemicals plants.