Process for the production of alkyltin halides
A process comprising: (a) contacting a feed stream comprising a di-alkyltin dihalide distillate with an alkylation agent, thereby forming an alkylated mixture comprising R 4 Sn and optionally R 3 SnX, R 2 SnX 2 , or mixtures thereof, where R is a linear, branched or cyclic C 1 -C 20 alkyl, and X is a halide; (b) contacting the alkylated mixture with SnX 4 , thereby forming an alkyltin halide mixture comprising RSnX 3 , R 2 SnX 2 , and optionally impurities, R 3 SnX or mixtures thereof; (c) separating by distillation the alkyltin halide mixture to form a mono-alkyltin halide-rich distillate stream and a liquid di-alkyltin halide-rich bottoms stream comprising R 2 SnX 2 , RSnX 3 , and optionally impurities, R 3 SnX, or mixtures thereof; (d) separating by distillation the di-alkyltin halide-rich bottoms stream, thereby forming the liquid di-alkyltin dihalide distillate comprising R 2 SnX 2 , and optionally RSnX 3 , R 3 SnX or mixtures thereof, and an impurities-rich bottoms stream; and (e) recycling a part, x recycle , of the liquid di-alkyltin dihalide distillate to step (a), where x recycle ranges from greater than 0.0% to 100.0% of the distillate.
1. A process for producing mono-alkyltin and di-alkyltin bis(thioglycolate ester) streams comprising:
(a) contacting a feed stream comprising a di-alkyltin dihalide distillate with an alkylation agent, thereby forming an alkylated mixture comprising R 4 Sn and optionally R 3 SnX, R 2 SnX 2 , or mixtures thereof, where R is a linear, branched or cyclic C 1 -C 20 alkyl, and X is a halide;
(b) contacting the alkylated mixture with SnX 4 , thereby forming an alkyltin halide mixture comprising RSnX 3 , R 2 SnX 2 , and chromophoric impurities, R 3 SnX or mixtures thereof;
(c) separating by distillation the alkyltin halide mixture to form a mono-alkyltin halide-rich distillate stream having a boiling point of 150-250° C. at less than 10 mm Hg and a liquid di-alkyltin halide-rich bottoms stream comprising 70.0 to 97.0 wt % R 2 SnX 2 , 3.0 to 30.0 wt % RSnX 3 , chromophoric impurities, and optionally R 3 SnX;
(d) separating by distillation the liquid di-alkyltin halide-rich bottoms stream at a temperature of 200-220° C. at less than 5 mm Hg vacuum, thereby forming a separated liquid di-alkyltin dihalide distillate comprising 90.0 to 100.0 wt % R 2 SnX 2 , and at most 10.0 wt % RSnX 3 , having a Gardner color value of 2 or less, and an impurities-rich bottoms stream comprising chromophoric impurities;
(e) recycling a part, X recycle , of the separated liquid di-alkyltin dihalide distillate to step (a), thereby forming a recycled dihalide distillate stream and a non-recycled dihalide distillate stream, where X recycle ranges from greater than 10.0% to 90.0% of the separated liquid di-alkyltin dihalide distillate;
(f) reacting the non-recycled liquid di-alkyltin dihalide distillate with iso-octylmercaptoacetate, 2-ethylhexylmercaptoacetate, or n-octylmercaptoacetate, to form the corresponding di-alkyltin bis(thioglycolate ester)-containing stabilizer, wherein the di-alkyltin bis(thioglycolate ester)-containing stabilizer has a Gardner color value of at most 3.
2. The process of claim 1 wherein the separated liquid di-alkyltin dihalide distillate comprises R 2 SnX 2 and RSnX 3 .
3. The process of claim 1 wherein the separated liquid di-alkyltin dihalide distillate comprises R 2 SnX 2 and R 3 SnX.
4. The process of claim 3 wherein the separated liquid di-alkyltin dihalide distillate further comprises RSnX 3 .
5. The process of claim 1 wherein the alkylation agent is selected from a C 1 -C 20 tri-alkylaluminum compound, or a C 1 -C 20 alkylmagnesium halide compound.
6. The process of claim 1 wherein R is n-octyl.
7. The process of claim 1 wherein the halide is chloride.
8. The process of claim 1 wherein RSnX 3 is mono-n-octyltin trichloride.
9. The process of claim 1 wherein R 2 SnX 2 is di-n-octyltin dichloride.
10. The process of claim 1 wherein X recycle is 30.0% to 80.0%.
11. The process of claim 10 wherein X recycle is 50.0% to 70.0%.
12. The process of claim 1 wherein the mono-alkyltin halide-rich distillate stream of step (c) comprises 90.0 to 100 wt % RSnX 3 , 0.0 to 10.0 wt % R 2 SnX 2 and less than 1.0 wt % R 3 SnX.
13. The process of claim 1 wherein the non-recycled liquid di-alkyltin dihalide distillate is reacted with 2-ethylhexyl mercaptoacetate.
14. The process of claim 1 wherein the Gardner color value of the separated liquid di-alkyltin dihalide distillate of step (d) is at most 1.
15. The process of claim 1 wherein the chromophoric impurities are ligand precursors, hydrolyzed ligand precursors, tin halides, solvents, alkenes, alkyl halides, neutralization salts or mixtures thereof.
16. The process of claim 1 wherein the alkylated mixture formed in step (a) comprises a Gardner color value of at most 3.
17. The process of claim 1 wherein the R 2 SnX 2 content of the separated liquid di-alkyltin dihalide distillate of step (d) is from 97.0 to 100.0 wt %.
18. A process for producing a di-alkyltin oxide-containing catalyst stream comprising:
(a) contacting a feed stream comprising a di-alkyltin dihalide distillate with an alkylation agent, thereby forming an alkylated mixture comprising R 4 Sn and optionally R 3 SnX, R 2 SnX 2 , or mixtures thereof, where R is a linear, branched or cyclic C 1 -C 20 alkyl, and X is a halide;
(b) contacting the alkylated mixture with SnX 4 , thereby forming an alkyltin halide mixture comprising RSnX 3 , R 2 SnX 2 , and chromophoric impurities, R 3 SnX or mixtures thereof;
(c) separating by distillation the alkyltin halide mixture to form a mono-alkyltin halide-rich distillate stream having a boiling point of 150-250° C. at less than 10 mm Hg and a liquid di-alkyltin halide-rich bottoms stream comprising 70.0 to 97.0 wt % R 2 SnX 2 , 3.0 to 30.0 wt % RSnX 3 , chromophoric impurities, and optionally R 3 SnX;
(d) separating by distillation the liquid di-alkyltin halide-rich bottoms stream at a temperature of 200-220° C. at less than 5 mm Hg vacuum, thereby forming a separated liquid di-alkyltin dihalide distillate comprising 90.0 to 100.0 wt % R 2 SnX 2 , and at most 10.0 wt % RSnX 3 , having a Gardner color value of 2 or less, and an impurities-rich bottoms stream comprising chromophoric impurities;
(e) recycling a part, X recycle , of the separated liquid di-alkyltin dihalide distillate to step (a), thereby forming a recycled dihalide distillate stream and a non-recycled dihalide distillate stream, where X recycle ranges from greater than 10.0% to 90.0% of the separated liquid di-alkyltin dihalide distillate;
(f) reacting a first portion of the non-recycled liquid di-alkyltin dihalide distillate with iso-octylmercaptoacetate, 2-ethylhexylmercaptoacetate, or n-octylmercaptoacetate, to form the corresponding di-alkyltin bis(thioglycolate ester)-containing stabilizer, wherein the di-alkyltin bis(thioglycolate ester)-containing stabilizer has a Gardner color value of at most 3, and reacting a second portion of the non-recycled liquid di-alkyltin dihalide distillate with water, thereby forming the di-alkyltin oxide-containing catalyst.
19. A process for producing mono-alkyltin rich and di-alkyltin rich streams comprising:
(a) contacting a feed stream comprising a liquid di-alkyltin dihalide distillate with a tri-alkyl aluminum compound, thereby forming an alkyltin halide mixture comprising RSnX 3 , R 2 SnX 2 , chromophoric impurities, and optionally R 3 SnX wherein the alkyltin halide mixture formed in step (a) has a Gardner color value of at most 3;
(b) separating by distillation the alkyltin halide mixture to form a mono-alkyltin halide-rich distillate stream having a boiling point of 150-250° C. at less than 10 mm Hg and a liquid di-alkyltin-rich bottoms stream comprising 70.0 to 97.0 wt % R 2 SnX 2 , 3.0 to 30.0 wt % RSnX 3 , chromophoric impurities, and optionally R 3 SnX or mixtures thereof;
(c) separating by distillation the liquid di-alkyltin halide-rich bottoms stream at a temperature of 200-220° C. at less than 5 mm Hg vacuum, thereby forming a separated liquid di-alkyltin dihalide distillate comprising 90.0 to 100.0 wt % R 2 SnX 2 , at most 10.0 wt % RSnX 3 , and optionally R 3 SnX; and an impurities-rich bottoms stream comprising chromophoric impurities; and
(d) recycling a fraction, X recycle , of the separated liquid di-alkyltin dihalide distillate to step (a), thereby forming a recycled liquid di-alkyltin dihalide distillate stream and a non-recycled liquid di-alkyltin dihalide distillate stream, where X recycle ranges from greater than 10.0% to 90.0% of the distillate product.
20. The process of claim 19 further comprising reacting the non-recycled dihalide distillate with an organic acid selected from the group consisting 2-ethylhexanoic acid, neodecanoic acid, lauric acid, myristic acid, oleic acid, and stearic acid, thereby forming a di-alkyltin bis-carboxylate-containing stabilizer or a catalyst.
21. The process of claim 19 wherein the R 2 SnX 2 content of the separated liquid di-alkyltin dihalide distillate of step (d) is from 97.0 to 100.0 wt %.