Catalytic reforming hydrogen production

Feeds and Products, Barrels per Calendar Day Refinery Input High Severity Hydrotreating Catalytic Reforming Hydrogen Manufacture Recovery and Sulfur Plant Refinery Fuel Motor Gasoline Kerosene Jet Fuel By- Products... 

The conversion products, other than gas and hydrogen sulfide (H2S), are essentially a gasoline fraction that, after pretreatment, will be converted by catalytic reforming an average quality distillate fraction to be sent to the gas oil pool and an atmospheric residue or vacuum distillate and vacuum residue whose properties and impurity levels (S, N, Conr. 

Mixtures of CO—H2 produced from hydrocarbons, as shown in the first two of these reactions, ate called synthesis gas. Synthesis gas is a commercial intermediate from which a wide variety of chemicals are produced. A principal, and frequendy the only source of hydrogen used in refineries is a by-product of the catalytic reforming process for making octane-contributing components for gasoline (see Gasoline and OTHER MOTOR fuels), eg. 

C, 0.356—1.069 m H2/L (2000—6000 fU/bbl) of Hquid feed, and a space velocity (wt feed per wt catalyst) of 1—5 h. Operation of reformers at low pressure, high temperature, and low hydrogen recycle rates favors the kinetics and the thermodynamics for aromatics production and reduces operating costs. However, all three of these factors, which tend to increase coking, increase the deactivation rate of the catalyst therefore, operating conditions are a compromise. More detailed treatment of the catalysis and chemistry of catalytic reforming is available (33—35). Typical reformate compositions are shown in Table 6. 

The process consists of a reactor section, continuous catalyst regeneration unit (CCR), and product recovery section. Stacked radial-flow reactors are used to minimize pressure drop and to facilitate catalyst recirculation to and from the CCR. The reactor feed consists solely of LPG plus the recycle of unconverted feed components no hydrogen is recycled. The liquid product contains about 92 wt% benzene, toluene, and xylenes (BTX) (Figure 6-7), with a balance of Cg aromatics and a low nonaromatic content. Therefore, the product could be used directly for the recovery of benzene by fractional distillation (without the extraction step needed in catalytic reforming). 

The catalytic combustor provides heat for the endothermic reforming reaction and the vaporization of liquid fuel. The endothermic reforming reaction is carried out in a parallel flow-type micro-channel of the reformer unit. It is well known that the methanol steam reforming reaction for hydrogen production over the Cu/ZnO/AbOs catalyst involves the following reactions [10]. Eq. (1) is the algebraic summation of Eqs. (2) and (3). 

Methanol production, where CO is added as additive, is very a well-known reaction. The production is carried out in two steps. The first step is to convert the feedstock natural gas into a synthesis gas stream consisting of CO, CO2, H20 and hydrogen. This is usually accomplished by the catalytic reforming of feed gas and steam. The second step is the catalytic synthesis of methanol from the synthesis gas. If an external source of C02 is available, the excess hydrogen can be consumed and converted to additional methanol. 

Aznar, M. P. Caballero, M. A. Corella, J. Molina, G. Toledo, J. M., Hydrogen production by biomass gasification with steam-02 mixtures followed by a catalytic steam reformer and a CO-Shift system. Energy and Fuels 2006, 20, 1305-1309. 

Abedi, J., Yeboah, Y.D., Howard, J., and Bota, KB. (2001) Development of a catalytic fluid bed steam reformer for production of hydrogen from biomass, 5th Biomass Conference of the Americas, Orlando, FL (Cancelled). Abstracts to be published on CD/ROM. 

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