Hydrocarbon catalytic partial oxidation

Ahmed, S. et al., Catalytic partial oxidation reforming of hydrocarbon fuels, Proc. of 1998 Fuel Cell Seminar, Palm Springs, CA, 242,1998. 

Private communication with Johnson Matthey Technology Centre, Reading, England, February 2000. 17. "Catalytic Partial Oxidation Reforming of Hydrocarbon Fuels," S. Ahmed, et al., ANL, Pg. 242, Fuel Cell Seminar Abstracts, Courtesy Associates, Inc., November 1998. 

Non-catalytic partial oxidation (POX) of hydrocarbons from residual fuel oils to methane is commercially proven by two processes, one offered by Texaco and the other by Shell. Davy has experience with both processes. Each process has a large number of plants in operation, with feeds varying from natural gas to high sulfur residual oil. (In fact, so long as the feedstock can be pumped, it is a suitable feestock for a partial oxidation gasifier. 

Ceramic Membranes for Oxygen Separation and Catalytic Partial Oxidation of Hydrocarbons... 

Gardner et al. reported that H2S catalytic partial oxidation technology with an AC catalyst is a promising method for the removal of H2S from fuel cell hydrocarbon feedstocks.206 Three different fuel cell feedstocks were considered for analysis sour natural gas, sour effluent from a liquid middle distillate fuel processor, and a Texaco 02-blown coal-derived synthesis gas. Their experimental results indicate that H2S concentration can be removed down to the part per million level in these plants. Additionally, a power-law rate expression was developed and reaction kinetics compared with prior literature. The activation energy for this reaction was determined to be 34.4 kJ/g mol with the reaction being first order in H2S and 0.3 order in 02. 

Several processes, including noncatalytic partial oxidation (POX), catalytic partial oxidation (CPO), and ATR may be used to perform partial oxidation of hydrocarbons. In all cases, some or all of the reactions listed in Table 4 are involved. Normally, these reactions are accompanied by the steam-reforming and shift reactions. The oxidation reactions are irreversible at all conditions of practical interest. 

Catalytic partial oxidation of hydrocarbons represents an important class among petrochemical reactions. Complete oxidation of hydrocarbons gives CO2, H2O. During the partial oxidation processes the conversion of a certain percentage of reactants and/or products to complete combustion products cannot be avoided. The main role of the catalyst in these reactions is to accelerate (at relatively lower temperatures) the reaction paths to the desired product without having the same effect on the paths to the complete combustion products. The partial oxidation reactions are usually consecutive or consecutive/parallel reactions with quite complex networks in many cases. 

Palladium membranes have been known for years, and the concept of a membrane reactor that would allow the continuous removal of a reaction product from an equilibrium controlled reactor has been discussed and to some degree practiced for several decades. Hydrogen production, via some type of hydrocarbon reforming or catalytic partial oxidation, coupled with the WGS reaction CO -I- H2O H2 -I- CO2 (AG° = -41 kJ/mole) is one application for such a membrane reactor. 

Ahmed, S. (1998), Catalytic Partial Oxidation Reforming of Hydrocarbon Fuels, 1998 Fuel Cell Seminar, California, p. 242, Elsevier, N.Y. 

A part from the steam reforming there are other interesting applications in the petrochemical industry methane dry reforming, catalytic partial oxidation, auto-thermal reforming, water gas shift, H2S cracking, and hydrocarbon dehydrogenation. More details about some of these applications are given in Chaps. 5, 6, 7, 8, and 9. 

A new horizon in S3mthesis gas production may be the process of catalytic partial oxidation (CPO) (59-61), of hydrocarbons, for example, the selective oxidation of methane... 

Newson, E. and Truong, T.B. (2003) Low-temperature catalytic partial oxidation of hydrocarbons (Cj—Cjo) for hydrogen production. Int. J. Hydrogen Energ., 28, 1379-1386. 

Ereni, S., Calogero, G. and Cavallaro, S. (2000) Hydrocarbon production from methane through catalytic partial oxidation reactions. J. Power Sources, 87, 28-38. 

Krummenacher, J.J., West, K.N. and Schmidt, L.D. (2003) Catalytic partial oxidation of higher hydrocarbons at millisecond contact times decane. 

Exxon (now ExxonMobil) has developed a two-step process for conversion of natural gas to liquid hydrocarbons. The process, referred to as AGC-21, utilizes a fluidized bed for catalytic partial oxidation/steam reforming of natural gas to syn gas, and a slurry bed reactor for conversion of the syn gas to hydrocarbons. The hydrocarbons are processed further to produce liquid products that are used as refinery or chemical plant feedstock. 

Contrary to the catalytic steam reforming, the non-catalytic partial oxidation process is also suitable for heavier hydrocarbons such as heavy oils, pitch or coal. Usually, oxidation takes place with prue oxygen. If air is used, the effort for the separation of nitrogen from the synthesis gas would be higher than for the air separation. The reaction is strongly exothermal and is realized uncooled in the... 

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