Methane steam reforming process

Marigliano, G., Barbieri, G. and Drioli, E. (2001) Effect of energy transport in a palladium based membrane reactor for methane steam reforming process. Catalysis Today, 67 (1-3), 85-99. 

Barbieri, G. DiMaio, F. Simulation of the Methane Steam reforming Process in a Catalytic Pd-Membrane Reactor Ind. Eng. Chem. Res. 36 (1997) 2121-2127. 

FIGURE 1.3 Equilihrium CO conversions of a typical reformate stream from a methane steam reforming process at various steam to dry gas (S/G) ratios. (Taken from D. Mendes, A. Mendes, L.M. Maderia, A. Lidianelli, JM. Sousa, A. Basile, Asia-Pac. J. Chem. Eng. 5 (2010) 111.)... 

De Falco M (2004) Pd-based membrane reactor a new technology for the improvement of methane steam reforming process. Thesis, University of Rome La Sapienza ... 

Hydrocarbons are converted into a mixture of hydrogen and oxides of carbon by reaction with steam over steam reforming catalysts. The reforming reaction is endothermic and the catalysts are packed into narrow tubes, which are heated in a furnace. The reforming furnace is commonly known as a reformer. An efficient methane steam reforming process was developed by 1936 and was first used on a large scale in North America during World War Two as shown in Ta-... 

Na.tura.1 Ga.s Reforma.tion. In the United States, most hydrogen is presently produced by natural gas reformation or methane—steam reforming. In this process, methane mixed with steam is typically passed over a nickel oxide catalyst at an elevated temperature. The reforming reaction is... 

Steam Reforming Processes. In the steam reforming process, light hydrocarbon feedstocks (qv), such as natural gas, Hquefied petroleum gas, and naphtha, or in some cases heavier distillate oils are purified of sulfur compounds (see Sulfurremoval and recovery). These then react with steam in the presence of a nickel-containing catalyst to produce a mixture of hydrogen, methane, and carbon oxides. Essentially total decomposition of compounds containing more than one carbon atom per molecule is obtained (see Ammonia Hydrogen Petroleum). 

Natural gas consists mainly of methane together with some higher hydrocarbons (Tab. 8.1). Sulfur, if present, must be removed to a level of about 0.2 ppm prior to the steam reforming process as it poisons the catalyst. This is typically done by cata-lytically converting the sulfur present as thiols, thiophenes or COS into H2S, which is then adsorbed stochiometrically by ZnO, at 400 °C, upstream of the reactor. 

Discuss the importance of the steam-reforming process for the production of hydrogen and synthesis gas. Is this process endothermic or exothermic What is the rate-limiting step for the steam reforming of methane ... 

Fuel reforming is popular way for hydrogen production for fuel cell use. Hydrocarbons are used for the fuel resource. Methane (CH4) steam reforming process consists of the following two gas phase reactions with various catalysts. 

The steam reformer process involves the reaction of methane and high temperature steam in the presence of a nickel catalyst. The reactions are... 

Biological conversion via anaerobic digestion is currently being practiced, resulting in methane that can be processed to hydrogen by conventional steam reforming processes. 

They used a Ni-containing catalyst. In contrast to steam reforming of methane, methane partial oxidation is exothermic. However, the partial oxidation requires pure oxygen, which is produced in expensive air separation units that are responsible for up to 40% of the cost of a synthesis gas plant (2) (in contrast, the steam reforming process does not require pure oxygen). Therefore, the catalytic partial oxidation of methane did not attract much interest for nearly half a century, and steam reforming of methane remained the main commercial process for synthesis gas manufacture. 

In this ideahzed, stoichiometric equation (Eq. 6.36), cellulose (represented as CjHj Oj) reacts with water to produce and CO, the conunercial production of Hjfrom methane by the catalytic steam reforming process (Wagner and Froment, 1992). 

A variety of low molecular weight hydrocarbons can be used as feedstock in the steam-reforming process. Equations are given for both methane (natural gas) and propane. The reaction occurs in two separate steps reforming and shift conversion. 

The necessary fuel processing of natural gas or other hydrocarbons and coal before its use in the SOFC changes the system design. The following investigations have been done for methane as the main component of natural gas to keep the calculations simple. A common type of fuel processing for hydrocarbons is the endothermic steam reforming process as shown for methane in Equation (2.105) with the heat demand Equation (2.106)... 

Considering methane steam reforming [see Eq. (2.12)] as a large-scale process, Xu and Froment found that only the outer 2 mm of the catalyst pellets actually participates in the reaction [41], thus theoretically allowing for a two orders of magnitude reduction in catalyst volume. However, the well-known pressure drop limitations have prevented practical applications in the industrial field so far. 

Large-scale production of hydrogen for fuel and chemicals starts from fossil fuels, typically by methane steam reforming (MSR) and WGS processes. 

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