Dehydrogenation Catofin

Figure 6-2. The Lummus Crest Catofin dehydrogenation process (1) reactor, (2) compressor, (3) liquid product recovery, (4) product purification.

CATOFIN [CATalytic OleFIN] A version of the Houdry process for converting mixtures of C3 - C5 saturated hydrocarbons into olefins by catalytic dehydrogenation. The catalyst is chromia on alumina in a fixed bed. Developed by Air Products Chemicals owned by United Catalysts, which makes the catalyst, and licensed through ABB Lummus Crest. Nineteen plants were operating worldwide in 1991. In 1994, seven units were used for converting isobutane to isobutylene for making methyl /-butyl ether for use as a gasoline additive. 

Maxofin A dehydrogenation process for converting tight hydrocarbons such as propane and isobutane into olefins and hydrogen. Competetive with Catofin and 01eflex. Under development by Mobil Research Development Corporation since 1995. 

Fig. 1.7. CATOFIN process dehydrogenation of propane adapted from Ullmann [54]. (a) charge heater (b) air heater (c) purge step (d) production step (e) regeneration step.

R. G. Craig, T. J. Delaney, J. M. Duffalo, Catalytic dehydrogenation performance of the catofin process. DeWitt Petrochemical Review, Houston 1990. 

Application Technology for dehydrogenation of propane (or isobutane) to make high-purity propylene (or isobutylene). The CATOFIN process uses specially formulated proprietary catalyst from Sud-Chemie. 

Commercial plants Currently, 11 CATOFIN dehydrogenation plants are onstream producing over 2,600,000 mtpy of isobutylene and 700,000 mtpy of propylene. 

The application of this technique to light paralhn dehydrogenation is known as the Catofin in ocess (see Sections Z3.4J2 and 62). 

The potential benefits which can be achieved by using ceramic membranes in comparison to conventional propane dehydrogenation processes such as Oleflex and Catofin will be discussed here. 

On behalf of KTI an experimental programme on these reactor concepts has been started at the University of Southern California (USC). Some of the experimental results, concerning the use of Knudsen diffusion membranes are available in the literature [32,40]. These data have been used to calculate the economics of an isothermal propane dehydrogenation membrane reactor concept and are compared with the commercial Oleflex and Catofin processes, based on an adiabatic concept. The experimental circumstances of these lab-scale experiments, especially residence time, pressures and gas composition are not the same as in commercial, large-scale processes. However, we do not expect these differences to have a great influence on the results of the work presented here. 

In the late 1980s, the application of chromia-alumina catalysts was extended by Houdry to the dehydrogenation of propane to propylene and isobutane to isobutylene. The new process application called Catofin operates on the same cyclic principle as in the former Catadiene process. As of late 2000, a total of eight Catofin units existed for the production of isobutylene (including two converted older Catadiene units) with an aggregate capacity of about 2.8 million metric tons per annum (MTA) of isobutylene. In addition, two Catofin units were built for the production of propylene, but it is understood that only... 

Craig, R.G. Spence, D.C. Catalytic dehydrogenation of liquefied petroleum gas by the Houdry Catofin and Catadiene processes. In Handbook of Petroleum Refining Processes, Robert, A.M., Ed. McGraw-Hill, 1986 Section 4.1. 

Gussow, S. Whitehead, R. Isobutane dehydrogenation by Catofin as feed for motor fuel ether, NPRA Annual Meeting, National Petroleum Refiners Association (NPRA) San Antonio, TX, Mar 17-19, 1991. 

Several commercial processes have been developed for the catalytic dehydrogenation of propane to propylene as presented in Table 4. Of the seven commercial propane dehydrogenation plants in operation, six use UOP s Oleflex continuous moving-bed process. The other uses ABB Lummus Catofin cyclic multiple-reactor system. Other processes include Krupp Uhde s STAR process, as well as technologies from Linde and Snamprogetti. ... 

They also evaluated isothermal MR concepts and compared them in performance with the adiabatic Catofin and Oleflex processes. They studied two different type processes using Knudsen diffusion membranes a process called CMRL, patterned after the commercial Oleflex process, with low propane conversion, and a process called CMRH, patterned after the commercial Catofin process with high propane conversion. They have calculated the return on investment (ROI) for all four processes. Though marginally better than the commercial processes, the ROI for all four processes evaluated is not very attractive. A sensitivity analysis indicates that for the ROI of the MR processes to be attractive a price difference between propane and propylene of more that 300/ton is required. Though published calculations have only been performed for the propane/propylene pair, it is not unreasonable to assume that similar conclusions apply to other alkane/alkene pairs. Similar conclusions about catalytic alkane dehydrogenation have also been reached in a technical/economic evaluation study by Amoco workers and their academic collaborators (Ward et al [6.3 ]). 

Commercial plants Currently eight CATOFIN dehydrogenation plants are on stream producing over 1.8 million metric tpy of isobutylene and 1.16 million metric tpy of propylene. 

Lummus Technology Isobutylene Isobutane CATOFIN isobutane dehydrogenation process uses mulitple fixed-bed reactors in cyclic operation to produce isobutylene. 9 1996... 

Over the years, several processes for the catalytic dehydrogenation of propane to propylene have been developed, which can be divided into processes based on an adiabatic or an isothermal reactor concept, respectively. The processes currently apphed on an industrial scale are based on adiabatic systems, such as the Catofin (Lummus/Air Products) and the Oleflex (UOP) process. As the dehydrogenation of propane to propylene comprises an equihbrium reaction (11), selective removal of hydrogen from the reaction mixture can shift the reaction towards the product side. At high temperatures, thermal cracking may occur. 

Commercially, the oldest dehydrogenation process for the dehydrogenation of propane to propene is the Catofin process (113,114) developed in the late 1980s, which is based on catalysts Houdry developed in the mid-1940s. In this process, the feed is heated to 525-635°C and passed over a chromia-alumina catalyst. 

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