Claims
- 1. In a process for removing sulfur and nickel from a heavy hydrocarbon charge stock which contains from about 10 to about 3000 ppm total metals including nickel and from about 1 to about 10 weight percent sulfur by reaction of the charge stock with hydrogen in the presence of a desulfurization catalyst in a reactor with one or more catalyst beds including a first catalyst bed, the improvement comprising reducing the hydrogen partial pressure and enhancing sulfur and nickel removal by:
- (a) mixing said charge stock and a hydrogen-rich stream optionally containing water;
- (b) heating the mixture from step (a) to reaction temperature;
- (c) injecting said heated mixture and water into said reactor and reacting the resulting heated admixture in said first catalyst bed, said first catalyst bed containing desulfurization catalyst which consists of at least one metallic component selected from the Groups VIB and VIII of the Periodic Table deposited on a refractory inorganic oxide support, under desulfurization conditions, wherein the water to hydrogen molar ratio in the reaction is from about 0.05 to about 0.5;
- (d) separating a light gas stream which contains H.sub.2, H.sub.2 O, H.sub.2 S and light hydrocarbons from the effluent of said reaction zone;
- (e) separating the H.sub.2 O from said light gas stream leaving a substantially dry light gas stream;
- (f) recycling the separated H.sub.2 O for injection as in step (c);
- (g) separating from H.sub.2 S from the dry light gas stream leaving a hydrogen-rich stream;
- (h) recycling said hydrogen-rich stream for admixing with said charge stock, and
- (i) recovering the desulfurized and demetallized product from the effluent of said reaction zone; said water injected in steps (a) and (c) being at a temperature which is not in excess of the reaction temperature in step (b).
- 2. The process of claim 1 wherein at least a portion of the water present in the reaction step (c) is injected with the hydrogen-rich stream.
- 3. The process of claim 1 wherein the conditions of step (c) comprise a pressure of about 500 to about 3000 psig and a temperature of about 250.degree. to about 500.degree. C.
- 4. The process of claim 1 wherein said catalyst comprises cobalt and molybdenum in either the oxide or sulfide form deposited on alumina.
- 5. The process of claim 1 wherein water is injected into said reaction zone at a water to hydrogen molar ratio from about 0.5 to about 0.2.
- 6. The process of claim 1 wherein separation of step (d) is effected by a high temperature flash.
- 7. The process of claim 1 wherein the admixture of step (a) comprises from about 1000 to about 20,000 SCF H.sub.2 /BBL.
- 8. The process of claim 1 wherein the separation of step (e) is effected by condensation.
- 9. The process of claim 1 wherein said sulfur free and nickel-free product is conducted to a catalytic cracking zone and catalytically cracked products are withdrawn from said zone.
- 10. The process of claim 1 wherein said Group VIB metallic component of the catalyst of step (c) is present in an amount from 5-25 percent by weight and said Group VIII metallic component is present in an amount from 1-15 percent by weight.
- 11. The process of claim 1 wherein the reaction step (c) is conducted in one or more catalyst beds in addition to said first catalyst bed.
Parent Case Info
This application is a continuation of Ser. No. 671,906, filed Mar. 29, 1976, now abandoned.
US Referenced Citations (11)
Continuations (1)
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Number |
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671906 |
Mar 1976 |
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