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Catalysts paraffin/olefin conversion

The composition of the gasoline obtained by catalytic cracking and used as a feedstock for the ZSM-5 catalyst is given in Table VI. Product analyses, also given in Table VI, show that 80% of the olefins and less than 10% of the paraffins are converted by the ZSM-5 catalyst with about 30% of the olefin conversion attributable to the matrix present in the catalyst. This is not surprising due to the well-known higher reactivity of olefins. [Pg.44]

Light hydrocarbons (Ci to C4) and aromatics (mainly Ce to Ce) were produced by ZSM-5 due to the the conversion of olefins and paraffins. Thus,these results provide evidence for cracking of olefins, paraffins and cyclization of olefins by ZSM-5 at 500 C. The steam deactivated ZSM-5 catalyst exhibited reduced olefin conversion and negligible paraffin conversion activity. [Pg.44]

Earlier work in this laboratory showed that chromium oxide supported on alumina is a good catalyst for the conversion of olefins (ref. 1) as well as paraffins (ref. 2) to nitriles with high selectivities, by reaction of NO with the hydrocarbons (nitroxidation). Recent work (ref. 3) reported preliminary results of the nitroxidation of paraxylene as an extension of the use of C Oj-Al Oj to the catalytic synthesis of aromatic nitriles. It should be mentioned that only few data are available in the literature related to the nitroxidation of aromatic hydrocarbons. Teichner et al (ref. 4 ) reported interesting results of selective synthesis of benzonitrile by nitroxidation of toluene on NiO-AlgO catalysts. Improvements of the catalytic activity and selectivity in this reaction were reached by use of C Og-Al. which also exhibits striking properties in the synthesis of paratolunitrile by contact of NO with paraxylene (ref. 3). [Pg.455]

The high influence of cracking catalyst on PE conversion was confirmed by Aguado et al. [11] in a continuous screw kiln reactor. The application of a sophisticated laboratory Al-MCM-41 cracking catalyst and process temperature of 400-450°C led to 85-87% yield of gas and gasoline fractions (C1-C12). Besides olefins and n- and iso-paraffins some quantity of aromatics, 5 wt% was determined in the process products. In the same reactor system with a noncatalytic process the gas yield was halved while similarly as in case of the fluid reactor system yields of gas oil and heavy waxes fraction (C13-C55) attained values of 62% (compared with 4 wt% in catalytic process) [12]. [Pg.116]

The parafFin/olefin ratio as a function of conversion at different temperatures is shown in Figure 4 for MCM-41 and the equilibrium catalyst. Comparing the parafBn/olefm ratio obtained from these two catalysts at the same conversion levels (e.g. 50 %) it can be seen that MCM-41 produces a remarkably higher amount of unsaturated species. [Pg.395]

The overall path of methanol conversion to hydrocarbons over ZSM-5 is illustrated in Fig. 2. Methanol and dimethyl ether (DME) form olefins, which are then converted to naphthenes, aromatics, and paraffins. Olefins initially react by oligomerization and methylation, and at increasing conversion olefins distribution is governed by kinetics. This effect, and the effects of process variables were summarized by Chang (ref. 14). The directional effects of process and catalyst variables on the MTO reaction are summarized in Table 3. [Pg.311]

Methanol Conversion. Methanol conversion reactions based on borosilicate catalysts have been studied extensively (10.15,24,28.33.52-54). During the conversion of methanol, the reaction proceeds through a number of steps, to yield dimethylether, then olefins, followed by paraffins and aromatics. The weaker acid sites of borosilicate molecular sieves relative to those of aluminosilicates require higher reaction temperatures to yield aromatics. The use of less forceful process conditions leads to the formation of olefins selectively, instead of a mixture of paraffins, olefins, and aromatics (10.28.53.54). [Pg.537]

Inui et al. have investigated the influence of crystallization conditions of ZSM-34 zeolite on the attainment of a selective catalyst for olefin formation. They found that an optimum selectivity was obtained with a zeolite ZSM-34 crystallized for 25 to 30 days at 100 C. For shorter crystallization times, the principal product was dimethyl ether. For longer times paraffin selectivity increased, while olefin selectivity decreased. When the precursor was kept at 100 C for only 3 days and then heated to 190 C for 30 min, the resulting catalyst exhibited a better selectivity than zeolites prepared by standard methods. In this case, the conversion of methanol was about 96.9% and about 67.8% was... [Pg.11]

Romannikov et al. studied the catalytic properties of beryllium-silicates with a zeolite-type structure. Methanol conversion yielded primarily olefins, while on the isostructural aluminum-silicate catalyst paraffins and aromatics were obtained. The methanol conversion was considerably higher on the [AlJ-ZSM-5 than on the [Be]-ZSM-5, except in one example (Table 12). [Pg.38]

Raney nickel A porous solid catalyst made from an activated alloy of nickel and aluminium. The nickel is the catalytic metal with the aluminium as the structural support It was developed by American mechanical engineer Murray Raney (1885-1966) in 1926 for the hydrogenation of vegetable oil and is now used in hydrogenation reactions in various forms of organic synthesis. It is widely used as an industrial catalyst for the conversion of olefins and acetylenes to paraffins, nitriles, and nifro compounds to amines, and benzene to cyclohexane amongst others. [Pg.314]

C with low conversion (10—15%) to limit dichloroalkane and trichloroalkane formation. Unreacted paraffin is recycled after distillation and the predominant monochloroalkane is dehydrochlorinated at 300°C over a catalyst such as nickel acetate [373-02-4]. The product is a linear, random, primarily internal olefin. [Pg.459]

Mobil MTG and MTO Process. Methanol from any source can be converted to gasoline range hydrocarbons using the Mobil MTG process. This process takes advantage of the shape selective activity of ZSM-5 zeoHte catalyst to limit the size of hydrocarbons in the product. The pore size and cavity dimensions favor the production of C-5—C-10 hydrocarbons. The first step in the conversion is the acid-catalyzed dehydration of methanol to form dimethyl ether. The ether subsequendy is converted to light olefins, then heavier olefins, paraffins, and aromatics. In practice the ether formation and hydrocarbon formation reactions may be performed in separate stages to faciHtate heat removal. [Pg.165]


See other pages where Catalysts paraffin/olefin conversion is mentioned: [Pg.17]    [Pg.94]    [Pg.327]    [Pg.328]    [Pg.332]    [Pg.334]    [Pg.88]    [Pg.510]    [Pg.522]    [Pg.104]    [Pg.5]    [Pg.42]    [Pg.355]    [Pg.515]    [Pg.327]    [Pg.328]    [Pg.332]    [Pg.334]    [Pg.127]    [Pg.489]    [Pg.226]    [Pg.78]    [Pg.363]    [Pg.483]    [Pg.156]    [Pg.18]    [Pg.47]    [Pg.227]    [Pg.122]    [Pg.127]    [Pg.21]    [Pg.56]    [Pg.199]    [Pg.2376]    [Pg.225]    [Pg.76]    [Pg.44]   
See also in sourсe #XX -- [ Pg.519 ]




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Olefin conversion

Olefins paraffins

Paraffin catalysts

Paraffin conversion

Paraffins conversion catalysts

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