Naphtha reformers

Currendy, there are three commercially available PX adsorption processes UOP s Parex, IFP s Eluxyl, and Toray s Aromax (not to be confused with Chevron s Aromax process for reforming naphtha into aromatics). In all of these processes, the feed and desorbent inlets and the product oudet ports are moved around the bed, simulating a moving bed. 

In addition to straight run naphthas, 70—190°C cuts obtained by distillation from streams produced by cracking high boiling petroleum fractions can also be used as feed to reformers. Naphthas produced by hydrocracking are particularly suitable. 

In Europe, synthesis gas is mainly produced by steam reforming naphtha. Because naphtha is a mixture of hydrocarbons ranging approximately from C5-C10, the steam reforming reaction may be represented using n-heptane ... 

Catforming a process for reforming naphtha using a platinum-silica-alumina catalyst which permits relatively high space velocities and results in the production of high-purity hydrogen. 

Results showed that the two-stage TCH process could be used for upgrading Athabasca bitumen and for producing reformer naphtha feedstock, fuel oils, and catalytic cracking gas-oil feedstock. Product weight yields ranging from 86.4% to 93.0% were obtained. A 3 wt % CoO-15 wt % Mo03 on alumina catalyst was found to be sufficiently active to produce specification distillates. Comparison of various catalysts showed some differences in selectivities. However, extended life studies should be carried out to substantiate the differences. 

Catalytic reforming Naphtha hydrotreating Distillate hydrotreating Gas oil desulfurization Resid desulfurization Resid hydrocracking... 

The feedstock consists of a mixture of C8 aromatics typically derived from catalytically reformed naphtha, hydrotreated pyrolysis gasoline oran LPG aromatization unit. The feed may contain up to 40% ethylbenzene, which is converted either to xylenes or benzene by the Isomar reactor at a high-conversion rate per pass. Feedstocks may be pure solvent extracts or fractional heartcuts containing up to 25% nonaromatics. Hydrogen may be supplied from a catalytic reforming unit or any suitable source. Chemical hydrogen consumption is minimal. 

Gasoline is usually produced as a blend of several petroleum streams that boil in the range of naphtha. A typical gasoline might contain 50% by volume of cracked naphtha with benzene content between 0.5 wt% and 2.0 wt% and 25% by volume of catalytically reformed naphtha with benzene content between 1 wt% and 3 wt%. Estimate the cost per gallon of gasoline of reducing the final benzene content to 0.62% by volume. Compositions of other components in the naphtha streams can be found in the patent literature. 

Fig. 19. Relationship between temperature requirement for reforming naphtha to 98 O.N. level and the activity of the acidic function. Crossed points mark mechanically mixed composites.

Let us demonstrate Fig. 1.8 with an example. A process for steam reforming naphtha is carried out at HjO/HC - 10, SOO C, and 40 atm total pressure. A Ni/AIjOj catalyst, diameter 4 mm, 0 0.6, was tested in a pilot unit and gave 75% conversion at a GHSV of 5000 hr. For pressure drop reasons, the process designer wants to double the size of the particle but keep all conditions the same. Will this change the conversion ... 

Reformate A reformed naphtha upgraded in octane number by catalytic reforming. 

Substitute Natural Cas iSNG) Methane produced from synthesis gas derived from steam reforming naphthas, coal, or biomass. 

Steam reforming, naphtha, syngas, ammonia, hydrogen. 

The chemistry of reforming naphtha is considerably more complex than methane. Reforming naphtha with the general formula C,n)H,2n+2) proceeds according to the following reactions ... 

In reforming naphtha with a nickel-based catalyst, three phenomena occur simultaneously. The first is decomposition of naphtha into lower molecular weight unsaturated intermediates. As this is essentially a cracking process, the lower molecular weight intermediates contain double bonds or olefins. Second, there is the reaction of steam with olefinic intermediates. The third is cracking and polymerization of the olefinic fragments forming carbon. 

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