Hydrocarbon synthesis

摘要

In the synthesis of hydrocarbons and oxygenated derivatives from carbon monoxide and hydrogen by contact with a fluidized bed of powdered iron catalyst, the bed is maintained in fluidized condition, as evidenced by a high heat transfer coefficient, by adding more coarsely ground iron powder responsive to the tendency of the powdered iron in the bed to disintegrate into smaller particles. The particle size of the catalyst bed is desirably maintained so that a major proportion of the particles are greater than 20 microns and preferably there is less than 20-25 per cent of fines of less than 20 microns. Where the percentage of such fines approaches 30-40, coarse material of 80-200 micron size is added in amount of, say, 60 per cent of the total weight of catalyst so that a major proportion of the catalyst particles has a particle size of 80-200 microns. Preferred temperatures are 525-650 DEG F. and pressures 250-700 p.s.i. The lowering of the heat transfer coefficient as catalyst particles disintegrate, and the increase after addition of coarse material is exemplified. Catalysts made from spent pyrites or catalyst used in ammonia synthesis are suitable. Regeneration may be effected by burning off carbon, resintering, and grinding if necessary. Such regenerated catalyst may be that of 80-200 microns added to the fluidized bed.ALSO:In the synthesis of hydrocarbons and oxygenated derivatives from carbon monoxide and hydrogen by contact with a fluidized bed of powdered iron catalyst, the bed is maintained in fluidized condition, as evidenced by a high heat transfer coefficient, by adding more coarsely ground iron powder responsive to the tendency of the powdered iron in the bed to disintegrate into smaller particles. The particle size of the catalyst bed is desirably maintained so that a major proportion of the particles are greater than 20 microns and preferably there is less than 20-25 per cent of fines of less than 20 microns. When the percentage of such fines approaches 30-40, coarse material of 80-200 micron size is added in amount of, say, 60 per cent of the total weight of catalyst so that a major proportion of the catalyst particles has a particle size of 80-200 microns. Preferred temperatures are 525-650 DEG F., and pressures 250-700 p.s.i. The lowering of the heat transfer coefficient as catalyst particles disintegrate, and the increase after addition of coarse material is exemplified. Catalysts made from spent pyrites or catalyst used in ammonia synthesis are suitable. Regeneration may be effected by burning off carbon, resintering, and grinding if necessary. Such regenerated catalyst may be that of 80-200 microns added to the fluidized bed.