Method of purifying dimethyl sulfoxide

Abstract

A method of purifying dimethyl sulfoxide includes distilling a dimethyl sulfoxide-containing liquid in the presence of sodium carbonate under a reduced pressure in an inert gas atmosphere to distill out dimethyl sulfoxide, an amount of the sodium carbonate with respect to 100 g of pure dimethyl sulfoxide in a residual liquid after the distillation being 6 times or more the amount of the sodium carbonate with respect to 100 g of the pure dimethyl sulfoxide in the dimethyl sulfoxide-containing liquid before the distillation.

1 . A method of purifying dimethyl sulfoxide comprising distilling a dimethyl sulfoxide-containing liquid in the presence of sodium carbonate under reduced pressure in an inert gas atmosphere to distill out dimethyl sulfoxide, an amount of the sodium carbonate with respect to 100 g of pure dimethyl sulfoxide in a residual liquid after the distillation being 6 times or more the amount of the sodium carbonate with respect to 100 g of the pure dimethyl sulfoxide in the dimethyl sulfoxide-containing liquid before the distillation. 
     
     
         2 . The method according to  claim 1 , wherein the distillation is performed by adding, at a start of the distillation, the sodium carbonate in an amount of 0.0005 to 1.0 g with respect to 100 g of the pure dimethyl sulfoxide in the dimethyl sulfoxide-containing liquid. 
     
     
         3 . The method according to  claim 1 , wherein the amount of the sodium carbonate with respect to 100 g of the pure dimethyl sulfoxide in the residual liquid after the distillation is 6 to 1000 times the amount of the sodium carbonate with respect to 100 g of the pure dimethyl sulfoxide in the dimethyl sulfoxide-containing liquid before the distillation. 
     
     
         4 . The method according to  claim 1 , wherein the amount of the sodium carbonate in the residual liquid after the distillation is 0.01 to 100 g with respect to 100 g of the pure dimethyl sulfoxide in the residual liquid after the distillation. 
     
     
         5 . The method according to  claim 1 , wherein, after water in the dimethyl sulfoxide-containing liquid is distilled out as an early distillate, the dimethyl sulfoxide is distilled out as a main distillate. 
     
     
         6 . The method according to  claim 1 , wherein the purified dimethyl sulfoxide has a purity of 99.990 area % or more. 
     
     
         7 . The method according to  claim 1 , wherein the sodium carbonate is used as an inhibitor for dimethyl sulfoxide decomposition. 
     
     
         8 . The method according to  claim 2 , wherein, after water in the dimethyl sulfoxide-containing liquid is distilled out as an early distillate, the dimethyl sulfoxide is distilled out as a main distillate. 
     
     
         9 . The method according to  claim 3 , wherein, after water in the dimethyl sulfoxide-containing liquid is distilled out as an early distillate, the dimethyl sulfoxide is distilled out as a main distillate. 
     
     
         10 . The method according to  claim 4 , wherein, after water in the dimethyl sulfoxide-containing liquid is distilled out as an early distillate, the dimethyl sulfoxide is distilled out as a main distillate. 
     
     
         11 . The method according to  claim 2 , wherein the purified dimethyl sulfoxide has a purity of 99.990 area % or more. 
     
     
         12 . The method according to  claim 3 , wherein the purified dimethyl sulfoxide has a purity of 99.990 area % or more. 
     
     
         13 . The method according to  claim 4 , wherein the purified dimethyl sulfoxide has a purity of 99.990 area % or more. 
     
     
         14 . The method according to  claim 5 , wherein the purified dimethyl sulfoxide has a purity of 99.990 area % or more. 
     
     
         15 . The method according to  claim 2 , wherein the sodium carbonate is used as an inhibitor for dimethyl sulfoxide decomposition. 
     
     
         16 . The method according to  claim 1 , wherein the distillation is performed at a reduced pressure of 10 to 750 Torr. 
     
     
         17 . The method according to  claim 1 , wherein the distillation is performed at a reduced pressure of 15 to 730 Torr. 
     
     
         18 . The method according to  claim 1 , wherein the distillation is performed at a temperature of 108° C. to 180° C. 
     
     
         19 . The method according to  claim 1 , wherein the distillation is performed at a temperature of 120° C. to 170° C. 
     
     
         20 . The method according to  claim 1 , wherein the distillation is performed at a. temperature of 131° C. to 160° C.