Process for producing alkali taurinate

Abstract

There is disclosed a process for producing alkali taurinate from alkali isethionate, alkali ditaurinate, or alkali tritaurinate by adding excess ammonia and at least of equal molar amount of an alkali hydroxide to a solution comprised of alkali ditaurinate, alkali tritaurinate, or their mixture and subjecting the solution to an ammonolysis to yield a solution comprised of alkali taurinate.

What is claimed is: 
     
         1 . A process for producing alkali taurinate from a solution comprised of alkali ditaurinate in a molar yield of at least 70% on the basis of alkali ditaurinate, comprising:
 (a) adding an alkali hydroxide and excess ammonia to a solution comprised of alkali ditaurinate, wherein the molar amount of alkali hydroxide is at least equal to the molar amount of sodium ditaurinate and wherein the alkali is lithium, sodium, or potassium; and   (b) subjecting the solution of step (a) to an ammonolysis to yield a solution comprised of alkali taurinate.   
     
     
         2 . A process for producing alkali taurinate from a solution comprised of alkali tritaurinate in a molar yield of at least 70% on the basis of alkali tritaurinate, comprising:
 (a) adding an alkali hydroxide and excess ammonia to a solution comprised of alkali tritaurinate, wherein the molar amount of alkali hydroxide is at least equal to the molar amount of sodium tritaurinate and wherein the alkali is lithium, sodium, or potassium; and   (b) subjecting the solution of step (b) to an ammonolysis to yield a solution comprised of alkali taurinate.   
     
     
         3 . A process for producing alkali taurinate from a solution comprised of alkali ditaurinate and alkali tritaurinate in a molar yield of at least 70% on the basis of total molar amount of alkali ditaurinate and alkali tritaurinate, comprising:
 (a) adding an alkali hydroxide and excess ammonia to a solution comprised of alkali ditaurinate and alkali tritaurinate, wherein the molar amount of alkali hydroxide is at least equal to the total molar amount of sodium ditaurinate and sodium tritaurinate and wherein the alkali is lithium, sodium, or potassium; and   (b) subjecting the solution of step (b) to an ammonolysis to yield a solution comprised of alkali taurinate.   
     
     
         4 . A process for producing alkali taurinate from a mother liquor solution in a molar yield of at least 70% on the basis of total molar amount of alkali ditaurinate and alkali tritaurinate in the mother liquor solution, comprising:
 (a) adding an alkali hydroxide and excess ammonia to a mother liquor solution, wherein the molar amount of alkali hydroxide is at least equal to the total molar amount of sodium ditaurinate and sodium tritaurinate in the mother liquor solution and wherein the alkali is lithium, sodium, or potassium; and   (b) subjecting the solution of step (b) to an ammonolysis to yield a solution comprised of alkali taurinate.   
     
     
         5 . The process according to  claim 4 , wherein the mother liquor solution is produced from alkali isethionate by a process comprising the steps of:
 (1) adding excess ammonia and optionally a catalyst to a solution comprised of alkali isethionate and optionally in the presence of alkali ditaurinate, alkali tritaurinate, their mixture, or the mother liquor solution, and subjecting the solution to ammonolysis, wherein the catalyst is an alkali hydroxide.   (2) removing excess ammonia from the solution of step (1) and neutralizing the solution with an acid to form a crystalline taurine suspension; and   (3) recovering taurine to obtain a mother liquor solution comprised of alkali ditaurinate and alkali tritaurinate.   
     
     
         6 . A process for producing alkali taurinate from a solution comprised of alkali isethionate and alkali ditaurinate in a molar yield of at least 80% on the basis of alkali isethionate, comprising:
 (a) adding an alkali hydroxide and excess ammonia to a solution comprised of alkali isethionate and alkali ditaurinate, wherein the molar amount of alkali hydroxide is at least equal to the molar amount of alkali ditaurinate and wherein the alkali is lithium, sodium, or potassium; and   (b) subjecting the solution of step (b) to an ammonolysis to yield a solution comprised of alkali taurinate.   
     
     
         7 . A process for producing alkali taurinate from a solution comprised of alkali isethionate and alkali tritaurinate in a molar yield of at least 80% on the basis of alkali isethionate, comprising:
 (a) adding an alkali hydroxide and excess ammonia to a solution comprised of alkali isethionate and alkali tritaurinate, wherein the molar amount of alkali hydroxide is at least equal to the molar amount of alkali ditaurinate and wherein the alkali is lithium, sodium, or potassium; and   (b) subjecting the solution of step (b) to an ammonolysis to yield a solution comprised of alkali taurinate.   
     
     
         8 . A process for producing alkali taurinate from a solution comprised of alkali isethionate, alkali ditaurinate, and alkali tritaurinate in a molar yield of at least 80% on the basis of alkali isethionate, comprising:
 (a) adding an alkali hydroxide and excess ammonia to a solution comprised of alkali isethionate, alkali ditaurinate, and alkali tritaurinate, wherein the molar amount of alkali hydroxide is at least equal to the total molar amount of alkali ditaurinate and alkali tritaurinate and wherein the alkali is lithium, sodium, or potassium; and   (b) subjecting the solution of step (b) to an ammonolysis to yield a solution comprised of alkali taurinate.   
     
     
         9 . A process for producing alkali taurinate from a solution comprised of alkali isethionate and a mother liquor solution in a molar yield of at least 80% on the basis of alkali isethionate, comprising:
 (a) adding an alkali hydroxide and excess ammonia to a solution comprised of alkali isethionate and a mother liquor solution, wherein the molar amount of alkali hydroxide is at least equal to the total molar amount of alkali ditaurinate and alkali tritaurinate and wherein the alkali is lithium, sodium, or potassium; and   (b) subjecting the solution of step (b) to an ammonolysis to yield a solution comprised of alkali taurinate.   
     
     
         10 . The process according to  claim 9 , wherein the mother liquor solution is produced from the alkali isethionate by a process comprising the steps of:
 (1) adding excess ammonia and optionally a catalyst to a solution comprised of alkali isethionate and optionally in the presence of alkali ditaurinate, alkali tritaurinate, their mixture, or the mother liquor solution, and subjecting the solution to ammonolysis, wherein the catalyst is an alkali hydroxide.   (2) removing excess ammonia from the solution of step (1) and neutralizing the solution with an acid to form a crystalline taurine suspension; and   (3) recovering taurine to obtain a mother liquor solution comprised of alkali ditaurinate and alkali tritaurinate.