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Propane dehydrogenation (PDH) technology and catalyst moving beds: 1. Honeywell UOP’s Oleflex process utilizes radial-flow moving-bed reactors; under operating conditions of 600°C to 700°C and a pressure of over 0.1 MPa, it achieves a single-pass conversion rate of 35% to 40% for propane, with an propylene selectivity of 84% to 89%, and allows for the online replacement of catalysts. Its latest DeH-26 catalyst extends the catalyst life to 4 years while improving hydraulic performance. The Oleflex process has been commercially available since 1990, and currently there are over 60 units worldwide that utilize the C3 Oleflex technology. 2 The propane dehydrogenation to propylene (PDH) process developed jointly by Luoyang Engineering Company (LPEC&GPEC) and the China Institute of Petroleum Sciences was recently approved following a review conducted by the group company. This process package has an annual capacity of 600,000 tons for the production of propylene via propane dehydrogenation using a moving bed technology. The process uses the PST-100 catalyst from the Chinese Academy of Sciences, for which no reports of industrial application have been seen to date. Fixed-bed: 1. ABB Lummus’ Catofin process. The Catofin process uses adiabatic fixed-bed reactors, and Clariant supplies the proprietary Cr2O3/Al2O3 catalyst; under conditions of 540–640°C and a pressure of over 0.05 MPa, the one-pass conversion rate of propane is 45%–50%, with a selectivity of over 88%. Clariant has recently introduced its latest propane dehydrogenation catalyst, Catofin 311, which offers improved selectivity compared to the previous generation of catalysts. Over the past two years, a total of 11 new propane dehydrogenation units worldwide have adopted the Catofin process. 2 ThyssenKrupp’s Star process employs a multi-chamber, multi-tube reactor with steam dilution; the reaction pressure is 0.5 MPa, and the catalyst used is Pt/Sn-zinc aluminate. The one-way conversion of propane is 30%~40%, with a selectivity of 85%~93%. 3 The PDH process used by German companies Linde and BASF, as well as the Norwegian company Statoil, involves multi-tube fixed-bed reactors with Cr2O3/Al2O3 catalysts; under conditions of a temperature of 590°C and a pressure of over 0.1 MPa, the conversion rate of propylene exceeds 90%. Subsequently, BASF developed Pt/zeolite catalysts, which, compared to the first generation of Cr-based catalysts, increased the one-pass conversion rate from 32% to 50%, and the overall conversion rate from 91% to 93%. However, no reports of industrial application have been seen to date. 4 Rezel’s ReFix-ProTM process The ReFix-ProTM process utilizes an adiabatic fixed-bed reactor, and it employs a proprietary Cr2O3/Al2O3 catalyst provided by Rezel Catalysts. Under conditions of 560–640°C and a pressure of over 0.1 MPa, the one-pass conversion rate of propane is 45%–50%, with a selectivity of over 88%. Over the past two years, 2 propane dehydrogenation units in China have adopted the ReFix-ProTM process. Fluidized bed: 1. The FBD process developed by Italian company Snamprogetti and Russian company Yarsintz. This process uses a fluidized-bed reactor equipped with a reaction-regeneration system, and employs microsphere Cr2O3/Al2O3 catalysts. Under conditions of 580°C–630°C and 118–147 kPa, the one-pass conversion rate of propane is 40%, while the selectivity for propylene reaches 80%. It has currently been applied to one 130,000 tons per year isobutylene industrial plant in Russia, as well as to 5 isobutane and propane dehydrogenation plants. 2 KBR’s K-PRO process: In 2018, KBR introduced a new PDH process called K-PRO, which uses a coaxial continuous reactor along with a non-Cr/Pt proprietary catalyst, and enables the continuous regeneration of this catalyst. The propylene selectivity is 87%–90%, and the propane conversion rate reaches 45%. Compared to fixed-bed or moving-bed reactors, it can reduce investment by 20%~30%. In January 2020, an Asian PDH plant with a capacity of 600,000 tons per year received the first license for this technology. 3 Dow’s Fluidized Catalytic Dehydrogenation process (FCDh) The FCDh technology introduced by Dow Chemical in the United States in 2017 utilizes a fluidized bed reactor along with a Ga/trace Pt-Al2O3 catalyst; at pressures of 0.13–0.17 MPa, it achieves a selectivity of 92%–96% with a conversion rate of 43%–48%. Compared to the current leading fixed-bed PDH technology, it features a faster conversion rate, does not require hydrogen recycling, and needs smaller reaction equipment ； The catalyst has good stability, requires a low initial loading, and needs less precious metal ； The initial investment cost is low. This process can be integrated with ethylene cracking units; in 2019, Dow Corporation announced that it would upgrade its steam cracking plant in Louisiana, USA, by adopting this process to add an additional production capacity of 100,000 tons per year dedicated to propylene production, with the project expected to come online in 2021. 4 Rezel’s PropeNEXT™ process: This process utilizes a fluidized-bed reactor equipped with a reaction-regeneration system, and employs microsphere Cr2O3/Al2O3 catalysts. Under conditions of 570°C to 620°C and 125 to 150 kPa, the one-pass conversion rate of propane is greater than 40%, while the selectivity for propylene reaches 85%. It has currently been applied to one 200,000 tons per year propane dehydrogenation industrial plant in the Middle East, as well as to multiple isobutane dehydrogenation plants. 5 The propane/butane combined dehydrogenation (ADHO) technology of China University of Petroleum utilizes non-toxic, non-corrosive oxide catalysts that are not precious metals, and an efficient circulating fluidized bed reactor has been developed to support this technology. The one-pass conversion of alkanes, as well as the yield and selectivity of olefins, are low. Currently, there are very few companies in China that possess their own propane dehydrogenation/isobutane dehydrogenation technologies, and even fewer that are capable of implementing these technologies on an industrial scale. After more than 10 years of research and development, Runhe Catalyst Company has achieved industrial application in fluidized-bed and fixed-bed propane/deisobutane dehydrogenation units, as well as the corresponding catalysts (all of which have been granted invention patents). At the same time, Runhe Catalyst is currently the only company in the world capable of industrially producing fixed-bed, moving-bed, and fluidized-bed dehydrogenation catalysts simultaneously! We welcome you to call for discussions!