| 摘要 |
<p>Cyclic fluidised cracking process for S-contg. oils, in which (a) cracking is at 454-649 degrees C using a catalyst contg. (1) a molecular sieve and/or amorphous carrier and (2) a metal component of Na, Sc, Ti, Fe, Cr, Mo, Mn, Co, Ni, Sb, Cu, Zn, Cd, rare earth metal or Pb, or a cpd. of these, in amount sufficient to absorb at least 50% of the sulphur oxides formed in the regenerator; (b) the deactivated catalyst is stripped at 454-649 degrees C using a gas contg. steam in wt. ratio to (1) of 0.0005-0.025:1; (c) the stripped catalyst is regenerated at 566-788 degrees C; (d) >=50% of the sulphur oxides is absorbed by the catalyst, (e) the catalyst is recycled to the reactor; (f) a waste gas stream is drawn off from the regenerator contg. O2 and a low concn. of sulphur oxides; and (g) most of the absorbed SO2 is drawn off from the reactor and/or stripper as S-contg. gas e.g. H2S. Emission of sulphur oxides is reduced, together with amount of CO in the exhaust gas from regenerator, which causes after-burning in the pipes, etc. Regenerated catalyst with reduced coke content and higher activity and selectivity is obtained. Exhaust gas contains 0.2% vol. CO and can be discharged directly to the atmos.</p> |
