Naphtha, steam reforming

The first naphtha steam-reforming furnaces were operated by ICl in the U.K. There are now many similar plants in operation all over the world. 

Krupp Udhe Methanol Natural gas, LPG and heavy naphtha Steam reforming process cost-effectively manufactures methanol from varying feedstocks 11 NA... 

Carbon deposition is one of the luost serious problems of the steam reforming catalyst process (ref 1). The deposition of carbon on naphtha steam reforming catalysts depends ori the chemical composition of the hydrocarbon oil, the steam/carbon ratio in the feedstock, as well as the pi ocesa temperature and pressure, it is also affected by tlie presence of sulfur poisons Our past research of SNG catalysts ejiamined the nature of the carbon deposits as a function of the sulfur level on the catalyst (refs, 2 4). A small amount of sulfur was found to promote the formation of carbon that is non-reactive with steam and hydrogen under steam reforming reaction conditions. The continuous accumulation of this less reactive carbon [continuous carbon deposition (CCD)l on the catalyst surface leads to coke fouling Studies of the occurrence of CCD in our laboratory tests allow ua to predict, that coke fouling is likely to occur on the same catalyst used in real Indusl.rlal applications. 

Melo, F. and Morlanes, N. Synthesis, characterization and catalytic behaviour of NiMgAl mixed oxides as catalysts for hydrogen production by naphtha steam reforming. Catalysis Today, 2008, 133-135, 383. 

Carbon formation is a major concern in methane and naphtha steam reforming, but Fig. 8.26 shows that under reaction conditions only reaction... 

Xi, intrinsic = rate calculated with bulk fluid conditions The catalyst activity is calculated as a parameter, updated from operating data. 2.2 Naphtha Steam Reforming Kinetic Relationships... 

The mechanisms account for chemisorption of the hydrocarbon and steam, followed by a-scission of the carbon-carbon bonds. The resulting adsorbed Cj species react with adsorbed steam to form carbon monoxide and hydrogen. These mechanisms alone would result in no formation of methane, which is of course generated from naphtha feed stocks which are totally free of methane. Methane concentrations of 8 to 10 mole percent (dry basis) are typical at the outlet of industrial naphtha steam reformers. Methane is generated when the hydrogen partial pressure is sufficiently high so that the reverse of the methane reforming reaction ... 

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