| 摘要 |
<p>1,217,815. Catalytic hydrocracking. TEXACO DEVELOPMENT CORP. 9 June, 1969 [24 June, 1968], No. 29009/69. Heading C5E. In the production of motor gasoline and jet fuel a heavy hydrocarbon oil is hydrocracked in a first stage at 600-850‹ F. and 200- 10,000 p.s.i.g. using a catalyst of 2-10 wt. per cent Ni and 5-30 wt. per cent W as the sulphides on a support which contains 15-60 wt. per cent of a zeolite Y, modified by ion exchange to reduce its alkali metal content to less than 5 wt. per cent, and at least one of the amorphous metal oxides silica, alumina, silicaalumina, magnesia, zirconia and beryllia. The effluent from the first stage is separated into a hydrogen rich stream which can be recycled to the first stage after removal of H 2 S and NH 3 , and a liquid portion from which a gasoline fraction is removed and the remainder passed to the second stage. A heavy hydrocarbon fraction boiling above 850‹ F., if present, can be recycled to the first stage or removed from the system. In the second stage, hydrocracking is carried out at 600-700‹ F. using a catalyst comprising 0À2-5 wt. per cent Pt or Pd on a support such as silica-alumina or the same as that used in the first stage. The effluent from the second stage is separated into a hydrogen rich gas, which is recycled to the second stage or to the first stage, a liquid which is fractionated to provide a gasoline fraction, a jet fuel fraction and a heavier fraction which is recycled to the first stage if more gasoline is required or to the second stage if more jet fuel is required. Suitable charge stocks to the first stage are straight run gas oil, catalytically cracked cycle gas oil, atmospheric residuum, shale oil, tar sand oil, and delayed coker gas oil and can contain 100-500 p.p.m. nitrogen.</p> |
