Hydroisomerization of benzene on the catalysts Pt/MOR/Al2O3
The process of hydroisomerization of benzene is one of the most promising processes to convert benzene to methylcyclopentane (MCP) - a more environmentally friendly and octane components of motor fuels. In this paper the authors study the characteristics of the hydroisomerization reaction of benzene to MCP on catalytic system Pt/MOR/Al2O3 (MOR-mordenite). Influence of acidic properties of the support and platinum predecessor (in the form of [Pt (NH3)4]Cl2 and H2PtCl6) on the yield of the desired product was studied in order to optimize the composition of the catalyst. Changing the acidity of the surface was carried out by the introduction of aluminum oxide in an amount of from 30 to 95 wt.% in the support. The catalytic activity of the samples was measured in the reactions of hydroisomerization of cyclohexane and benzene/ n-heptane (20/80 by weight) in a flow reactor in the temperature range 250-350 °C at a pressure of 1,5 MPa, H2/CH = 3/1, the volume rate filing of cyclohexane - 6 h-1, mixed raw material - 2 h-1, the amount of catalyst - 2 cm3, the fraction 0,25-0,75 mm. Found that the most efficient in the isomerization of cyclohexane, n-heptane and hydroisomerization of benzene is a platinum catalyst (0,3 wt.% Pt), whose support contains 30 wt.% MOR and 70 wt.% Al2O3. The maximum yield of target products of isomerization in the presence of that catalyst obtained in the temperature range 280-310 °C, what the thermodynamically favorable for the process of formation of methylcyclopentane from benzene, indicating that its prospects for application in hydroisomerization of benzene-containing gasoline fractions. Application H2PtCl6 acid as a precursor of platinum ensures the availability of reagents for the preparation of commercial batches of catalyst and attractive pricing for its industrial production.