| 摘要 |
<p>Catalyst for hydroforming petroleum hydrocarbons is based on a zeolite having an SiO2/Al2O3 ratio between 3 and 7 and an alkali metal content reduced to 2, preferably 0.5-0.04% wt. (as NaO). The zeolite is treated with ammonmium separately or simultaneously with deposition of a solution of W and/or Mo and a metal from the iron group (VIII) under conditions of pH >6.8, preferably 10-13. Preferably the Na content of the natural or synthetic zeolite is reduced by precalcination at 250-450 degrees C followed by treatment with boiling 2M NH4NO3 solution and calcination at 500-825, preferably 500-700 degrees C. Preferably tungstic acid, ammonium molybdate and a Ni or Co salt are deposited on the zeolite from a basic organic solvent (an alkylamine, alkanolamine, hydrazine or hydroxylamine) and the zeolite is subsequently recalcined at 400-650 degrees C. Used especially for single stage hydroforming of petroleum hydrocarbons boiling point 350 degrees C by treatment at 250-450 degrees C with 30-200 kg/cm2 partial pressure of H2 at throughputs of 0.2-10 litres hydrocarbon per litre catalyst per hour and 250-5000 litres H2 per kg hydrocarbon. Also suitable for hydrocracking hydrocarbon liquids including gas oils and asphalt residues. The reduced Na content and good dispersion of the active metals (W, Mo) present results in high catalyst activity, allowing higher than usual feedstock throughputs or use of lower temperatures. The catalysts remain active in the presence of nitrogenous bases and will tolerate some polyaromatic materials in the feedstock, and are easily regenerated by combustion and recalcination if necessary.</p> |
