Syngas methane partial

Koppers Hasche A cyclic process for converting methane to syngas by partial oxidation over an alumina catalyst ... 

C.-Y. Tsai, Y.H. Ma, W.R. Moser and A.G. Dixon, Simulation of nonisothermal catalytic membrane reactor for methane partial oxidation to syngas, in Y.H. Ma (Ed.), Proceedings of the 3rd International Conference on Inorganic Membranes, Worcester, 1994, pp. 271-280. 

Catalytic oxidation reactions on noble metal surfaces are sufficiently fast and exothermic that they can be operated at contact times on the order of one millisecond with nearly adiabatic temperatures of 1000°C. At short contact times and high temperatures complete reaction of the limiting feed is observed, and highly nonequilibrium products are obtained. We summarize experiments where these processes are used to produce syngas by partial oxidation of methane, olefins by partial oxidation of higher alkanes, and combustion products by total oxidation of alkanes. The former are used to produce chemicals, while the latter is used for high temperature catalytic incineration of volatile organic compounds. 

H2) where a complex network, involving secondary reactions of CO2 and H2O with CH4, enhance the yield of H2 and CO so that thermodynamic equilibrium can be reached easily [27]. It can be inferred that, like the oxidation of methane to syngas, the partial oxidation of methanol with a CH3OH/O2 ratio near to the stoichiometric value (ca. 2/1) operating with an optimum residence time and temperature can reach very high yields also approaching thermodynamic equilibrium. 

Figure 4 shows the model results (lines) along with e.xperimental data from steady state experiments (symbols) during methane partial oxidation with air on a Pt coated monolith for two feed temperatures. Obviousl . the model very closely reproduces both the catalyst temperature and methane conversion over the entire range of methane/air mixtures studied, while syngas selectivities are in less good agreement with the experiment. 

These estimates give only an upper limit of oxygen permeation rate because surface exchange reactions may result in some suppression of the overall transport. For the conditions typical for syngas generation (pO2=0.21 atm, pOj = 10 atm, 950°C), the results for the membranes with L = 0.1cm and different chromium contents are shown in Fig. 3. In the calculations at high pressures the ion conductivity values were assumed to be nearly equal to those at low pressures. Fig. 2. It is seen that the permeation rate in chromium doped samples is smaller than in the parent ferrite. Nonetheless, it may achieve a value of about 4 ml cm min in the sample with y = 1, which corresponds to the syngas production rate of about 20-25 ml-cm -min in the methane partial oxidation process. In combination... 

Au, C. and Wang, H. (1996). Pulse study of methane partial oxidation to syngas over Si02-supported nickel catalysts, Catal. Lett., 41, pp. 159-163. 

Kikuchi, E. and Chen, Y. (1998). Syngas Formationby Partial Oxidation of Methane in Palladium Membrane Reactor. Stud. Surf. Sci. Catal., 119, pp. 441 446. 

Controlled addition of a Production of syngas from partial oxidation of reactant or two reactants methane (membrane tube packed with Rhodium based reforming catalyst)... 

An important product made from methane is methanol. It involves an indirect route, also via the reforming of methane with water and oxygen to form syngas. Direct partial oxidation of methane is not sufficiently selective to make methanol or formaldehyde. Methanol is made from syngas by passing it over a copper zinc oxide catalyst The selectivity is very high and thus the impetus for development of other routes such as direct oxidation is not extremely high. 

Synthesis gas, a mixture of CO and o known as syngas, is produced for the oxo process by partial oxidation (eq. 2) or steam reforming (eq. 3) of a carbonaceous feedstock, typically methane or naphtha. The ratio of CO to may be adjusted by cofeeding carbon dioxide (qv), CO2, as illustrated in equation 4, the water gas shift reaction. 

Carbon Dioxide Removal. Aside from contained carbon dioxide which is removed from syngas when absorbing hydrogen sulfide, the total carbon dioxide produced in the methanation system is removed by conventional absorption in a single-stage operation in which the volume of gas to be treated is minimum and the partial pressure of the carbon dioxide is maximum. 

The two mechanisms proposed to account for the partial oxidation of methane to syngas may be dedgnated as the IPO (Indirect Partial Oxidation) mechanism and the DPO (Direct Partial Oxidation) mechanism. The IPO mechanism was proposed by Prette et al [16] and Lunsford et al [12]. They think CO and H2 are the products of indirect reaction, the overall reaction of the POM reaction is composed of three different reactions... 

---