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Joint conversion of the propane–butane fraction of gaseous С3–С4 alkanes and straight-run naphtha by involving them in the joint isomerization–disproportionation process on Ме/Н–N–SO42–/ZrO2 composite catalytic systems, where N is MOR or MFI zeolite or Al2O3, was studied at atmospheric pressure in the interval 160–240°С. The catalyst of the composition 0.4Со/HZSM-5/SO42– (2.0)–ZrO2 at 180°С allows up to 63.5% of gaseous C4– alkanes to be involved in isomerization–disproportionation processing of the mixture of straight-run naphtha and propane–butane fraction (1 : 1 by weight), the content of C5–C6 alkanes in the catalyzate to be increased by 21.4%, and the relative content of their branched isomers to be increased to 88.8%. The effect of hydrogen on the conversion of С4– and С8+ components of the mixture of straight-run naphtha and propane–butane fraction (1 : 1 by weight) was studied; an increase in the Н2/hydrocarbon ratio from 2 to 4 leads to an increase in the conversion of С4– alkanes from 63.5 to 90%. The possibility of expanding the resources for producing С5–С6 alkanes with increased content of high-octane branched components by joint processing of the propane–butane fraction and straight-run naphtha was demonstrated.

The catalysts were synthesized based on the spent industrial aluminum-chromium catalyst used in the hydrocarbon dehydrogenation by SABIC Co., and the catalysts were modified with copper and potassium carbonate. The catalysts were tested in the oxidative dehydrogenation of ethylbenzene to styrene. It was found that the prepared and modified 1 wt % Cu catalyst, upon the conversion of ethylbenzene to styrene in the presence of O2, exhibits an activity of 53% with a selectivity for styrene of 85%. It was shown that the introduction of carbon dioxide into the reaction zone leads to an increase in activity to 60–63%, and selectivity to 89–91%. The stability of the functioning of a copper-promoted catalyst and the effect of water vapor on the process were studied. It was found that under conditions close to industrial, within 100 h, a stable conversion of the mixture (ethylbenzene : O2 = 9 : 1) : H2O = 4 : 1 with a selectivity for styrene of at least 90% at a space velocity of 2 h–1 (at liquid ethylbenzene).

The conversion of straight-run naphtha on composite catalytic systems containing HZSM-5 zeolite modified with 0.4 wt % Co or Ni and 15% SZ (10% SO 4 2- /ZrO2), performed at atmospheric pressure in the interval 140–200°C, was studied. At 140–200°C, the major products of straight-run naphtha conversion are branched C5−C6 alkanes. At T ≥ 180°C, the reaction products become enriched in gaseous alkanes. Analysis of the conversion products suggests that the process occurs via formation of a skeleton-isomerized intermediate, followed by its cleavage (disproportionation) at the β- or α-bond. The conversion is influenced by the conditions of the reaction and reduction of the composite catalytic system. On the Co-containing composite catalyst reduced at 380°C, the conversion of C8+ components of straight-run naphtha at 180°C, feed space velocity of 2.5 h−1, and H2/CH = 3 is 76.8%, and the content of C5−C6 alkanes consisting to 78% of isoparaffins reaches 61%.

The conversion of n-C7H16, n-C4H10 and mixtures of C7H16: n-C4H10 = 1: 0.3 on the composite catalysts Al2O3/WO 4 2– ∙ZrO2 (A-WZ) and HMOR/ WO 4 2– ∙ZrO2 (M-WZ) at atmospheric pressure, H2/hydrocarbon = 3 and temperatures of 140-200°C was studied. It was found that a mixture of C7H16: n-C4H10 on M-WZ with high selectivity is converted into C5–C6 isomers. An assumption was made about the mechanism of the formation of the bimolecular intermediate C11, which decays earlier than occurs the formation of the products of the conversion of the mixture C7H16: n-C4H10.