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Cyclohexane is an important organic chemical raw materials and organic solvents, for the production of polyamide fiber products is one of important organic composition, may be hydrogenated benzene or petroleum distillate recovery system. With the rapid growth requirements cyclohexane, cyclohexane isolated from the crude oil in terms of quantity or quality can not meet the requirement, hence the hydrogenation of benzene to cyclohexane raw materials has become a mainstream approach. With Coke products refined technology matures development, the use of benzene in coking benzene was prepared from purified cyclohexane, has become coking products deep processing research directions. At present, the benzene hydrogenation catalyst used in the reaction are mainly metal, in order to improve the catalytic activity is often necessary to increase the amount of the noble metal loading, increasing the cost of the catalyst, the relatively poor economic efficiency. Therefore, the development of a noble metal can reduce the amount of load, economical and practical benzene hydrogenation catalyst, to reduce production costs and enhance our products in the deep processing of coal production capacity, market competitiveness and rational use of resources is especially important. Used in this study were prepared by impregnation of nickel-based catalyst, homemade integral reactor catalytic hydrogenation of benzene to cyclohexane reaction with benzene in the catalytic reaction conversion and selectivity of cyclohexane as a catalyst evaluation indicators, combined with XRD, TPR, IR and other characterization testing methods, respectively, through the optimization of operating conditions of the reaction, carrier selection, additives selection, carrier modification, preparation conditions and other means, prepared by gas phase hydrogenation of benzene cyclohexane catalytic process and catalyst developed a preliminary study. The main conclusions are: (1) a load mass fraction of 30% (Ni-30%) as a catalytic reaction of Ni/γ-Al2O3 catalysts of reaction temperature (T), the hydrogen - benzene molar ratio (n (H2 ) / n (C6H6)), benzene liquid space velocity (VLSP) and the reaction pressure (P) and other process parameters for nickel-based catalyst activity, and through orthogonal experiment, established the nickel-based catalysts for hydrogenation of the best Operating conditions: T is 200 ℃; H2/C6H6 to 6:1; VLSP of 0.5-1.Oh-1; P is 2.0MPa. (2) Select the γ-Al203 catalyst carrier, and Ti02 is different to Ni (NO3) 2 as the precursor to prepare a Ni-10% of Ni/γ-Al2O3 and Ni/TiO2 catalyst, and in the same process conditions Hydrogenation, Ni/y-Al203 catalytic reaction of benzene into 30.73%, while the Ni-TiO2 catalytic benzene conversion rate was 8.06%. And characterized by XRD analysis showed that H2-TPR, NiO uniformly dispersed in the γ-Al203 carrier surface, and in the TiO: crystallization appears on; reduction catalyst at different temperatures in different carriers Ni have different phases. (3) y-Al2O3 catalyst carrier was prepared mass fraction of 1% of La, Ce, Mo, Cu four different nickel-based catalyst loading aids, and in the same process carried out under catalytic hydrogenation conditions, La-Ni/γ-Al2O3 benzene catalyzed reaction conversion rate of 65.17 percent, the highest activity; Cu-Ni/γ-Al2O3 catalytic hydrogenation of benzene conversion rate 58.91%; Ce-Ni/γ-Al2O3 conversion rate was 46.92 %; while Mo-Ni/γ-Al203 of benzene conversion rate was 36.49%, thus, La, Cu Ni addition of additives at low load can be significantly increased amount of catalyst activity. In the XRD spectrum does not show diffraction peaks additives and NiO, with NiO All additives uniformly dispersed on the support surface. H2-TPR analysis showed Cu-NiO/γ-Al203 catalyst can begin restoring at 200 ℃, while adding other additives initial reduction temperature higher than 400 ℃. Infrared spectroscopy showed that the addition of different additives on Ni-O bond vibration peak degree of deviation differently. (4) Ti02, γ-Al203 as catalyst carrier, the carrier modified by phosphorylation, to obtain P-1%, Ni-10% of P-Ni/TiO2, P-Ni/γ-Al203 catalyst, the same process conditions Catalytic conversion of benzene under P-Ni/γ-Al203 57.17%, P-Ni/TiO2 catalyst was 25.10%, NiO dispersed on the support surface, can significantly increase the activity of the catalyst; but excessive phosphate modification, because the carrier NiO crystal is generated, it will cause reduced activity. (5) Select P-1%, Ni-10% of P-Ni/γ-Al2O3 catalyst was investigated in the preparation process of calcination temperature on activity. The experimental results showed that: in the calcination temperature range of 350-600 ℃, 450 ℃ when the catalytic conversion of benzene best, up 57.17 percent.
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