Claims
- 1. A process for the selective production of organic trisulfides of the formula R.sup.1 SSSR.sup.2 where R.sup.1 and R.sup.2 are independently C.sub.1 -C.sub.24 monovalent hydrocarbon radicals optionally having hydroxy or alkoxy substituent groups, said process comprising reacting in the absence of a polar solvent a first high sulfur rank polysulfide as the major sulfur source of the reaction, said polysulfide having the formula R.sup.1 SS.sub.x-1 SR.sup.2 where x is greater than 2 and R.sup.1 and R.sup.2 are as defined above, with an excess of a mercaptan of the structure R.sup.3 SH, where R.sup.3 is of the same description as R.sup.1 and R.sup.2, at a reaction temperature ranging from about 30.degree. to 120.degree. C. and in the presence of a heterogeneous catalyst which is a) an alumina-containing material, b) silica modified with at least 0.5 weight percent of either sodium, potassium, calcium or magnesium, or c) a zinc oxide-containing material, each of the recited catalysts being different in composition than the others, and terminating the reaction in sufficient time to permit recovery of a total product containing at least 70 weight percent of organic trisulfide of the above formula, at least a portion of which is the product of the reaction of said first high sulfur rank polysulfide and said mercaptan.
- 2. The process of claim 1 wherein said monovalent hydrocarbon radical is alkyl, aryl or alkaryl.
- 3. The process of claim 2 wherein the process is carried out in the presence of a catalyst which is an alumina-containing material.
- 4. The process of claim 2 wherein the process is carried out in the presence of a catalyst which is alumina, zinc oxide-alumina or titania-silica-alumina.
- 5. The process of claim 1 wherein said first high sulfur rank polysulfide is earlier prepared by reacting a mercaptan of the formula R.sup.3 SH wherein R.sup.3 is of the same description as R.sup.1 and R.sup.2 with elemental sulfur or a polysulfide of higher sulfur rank than said first polysulfide in the presence of a solid particulate catalyst.
- 6. The process of claim 5 wherein said mercaptan is prepared by reacting an olefin or alcohol corresponding to said mercaptan with hydrogen sulfide in the presence of a catalyst.
- 7. The process of claim 5 where, in the reaction for the production of trisulfide, R.sup.1 and R.sup.2 are alkyl radicals having 1 to 12 carbon atoms, the reaction ratio ranges between 1.7 to 10 moles of mercaptan to each g-atom of sulfur contributed by said first polysulfide, said reaction temperature ranges from 35.degree. to 100.degree. C., and the reaction pressure ranges between 0.015 psia to about 250 psig.
- 8. The process of claim 7 wherein the reaction for the production of trisulfide is carried out in the presence of a catalyst which is an alumina-containing material.
- 9. The process of claim 7 wherein said "alumina-containing material is alumina, zinc oxide-alumina, or titania-silica-alumina.
- 10. A process for the selective production of t-butyl, t-nonyl or t-dodecyl trisulfide which comprises reacting in the absence of a polar solvent, a first high sulfur rank polysulfide as the major sulfur source of the reaction, said polysulfide having the formula
- R.sup.1 SS.sub.x-1 SR.sup.2
- where R.sup.1 and R.sup.2 are t-butyl, t-nonyl or t-dodecyl and x is greater than 2, with its corresponding t-alkyl mercaptan at a reaction temperature ranging between 35.degree. and 100.degree. C., a reaction pressure ranging between about 0.015 psia and about 250 psig and at a reactant ratio of from 1.7 to 10 moles of mercaptan for each g-atom of sulfur contributed by said first polysulfide in the presence of a heterogeneous catalyst material which is alumina, zinc oxide-alumina, zinc oxide-silica-alumina, or titania-silica-alumina, and terminating the reaction in sufficient time to recover a total product containing at least 70 weight percent of the-corresponding t-alkyl trisulfide at least a portion of which is the product of the reaction of said first high sulfur rank polysulfide and said mercaptan.
- 11. The process of claim 10 wherein said first sulfur rank polysulfide is earlier prepared by reacting a mercaptan of the formula R.sup.3 SH wherein R.sup.3 is t-butyl, t-nonyl or t-dodecyl with elemental sulfur or a polysulfide of higher sulfur rank than said first polysulfide in the presence of a solid, particular catalyst.
- 12. The process of claim 11 wherein said mercaptan is prepared by reacting an olefin or alcohol corresponding to said mercaptan with hydrogen sulfide in the presence of a catalyst.
- 13. The process of claim 11 wherein any hydrogen sulfide generated during the preparation of said first polysulfide is removed from the presence of said first polysulfide before said polysulfide is used to prepare organic trisulfide.
- 14. The process for selective production of t-butyl trisulfide which comprises reacting in the absence of a polar solvent, a high sulfur rank polysulfide as the major sulfur source of the reaction, said polysulfide having the formula
- R.sup.1 SS.sub.x-1 SR.sup.2
- where R.sup.1 and R.sup.2 are t-butyl and x is greater than 2, with t-butyl mercaptan at a reaction temperature ranging between 35.degree. and 70.degree. C., a reaction pressure ranging between about 5 psia and about 250 psig, at a reactant ratio of from 5 to 10 moles of mercaptan to each g-atom of sulfur contributed by said polysulfide, for a time ranging from about 5 minutes to about 6 hours, and in the presence of a heterogeneous catalyst material which is alumina, zinc oxide-alumina, or titania-silica-alumina, and continuously removing any H.sub.2 S as it is formed during the reaction.
Parent Case Info
This is a continuation-in-part of application Ser. No. 07/748,377, filed on Aug. 22, 1991, now abandoned.
US Referenced Citations (9)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0337837 |
Oct 1989 |
EPX |
1162334 |
Aug 1959 |
GBX |
Non-Patent Literature Citations (2)
Entry |
Vineyard, B. D., Jour. Organic Chemistry 32, 3833-6 (Dec. 1967). |
Rabo, Zeolite Chemistry and Catalysis, ACS, 1976 p. 35. |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
748377 |
Aug 1991 |
|