Graded catalyst bed for methyl mercaptan synthesis
AssigneeChevron Phillips Chemical Company LP
InventorsDaniel M Hasenberg, Mitchell D Refvik
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Abstract
A process and graded catalyst bed for selectively producing methyl mercaptan from methanol. The methanol is reacted with hydrogen sulfide, in the presence of a graded catalyst bed containing at least three types of nickel or cobalt molybdenum alumina catalysts to convert the methanol to methyl mercaptan in one-pass. At least one of the hydrotreating catalysts can contain aluminium phosphate. Use of the graded catalyst bed prevents the formation of a hot spot within the graded catalyst bed. The methyl mercaptan having less than about 30 wt. % unreacted methanol contained therein.
Claims15
A process for selective production of methyl mercaptan comprising the steps of:
- (a) contacting methanol and hydrogen sulfide with a graded catalyst bed, the graded catalyst bed comprising at least three catalysts having an activity for converting methanol to methyl mercaptan that increases from an inlet to an outlet of the graded bed and from a first catalyst to a second catalyst to a third catalyst;
- and
- (b) reacting the methanol and the hydrogen sulfide to produce a reactor effluent comprising the methyl mercaptan while maintaining near isothermal conditions during reaction of the methanol and the hydrogen sulfide.
A process for selective production of methyl mercaptan comprising the steps of:
- (a) contacting methanol and hydrogen sulfide with a graded catalyst bed comprising at least three catalysts having an activity for converting methanol to the methyl mercaptan that increases from a first catalyst to a second catalyst to a third catalyst, the first catalyst being located upstream of the second catalyst and the second catalyst being located upstream of the third catalyst, the hydrogen sulfide and methanol being fed at a hydrogen sulfide to methanol molar feed ratio that ranges from about 6:1 to about 20:1;
- and
- (b) reacting the methanol and the hydrogen sulfide to produce a reactor effluent comprising the methyl mercaptan while maintaining near isothermal conditions during reaction of the methanol and the hydrogen sulfide, the reactor effluent comprising less than about 20 wt. % dimethyl sulfide.
Dependencies are inferred from the claim text.