There is disclosed a process for producing taurine in a molar yield of at least 80% 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.

There is disclosed a process for producing taurine in a molar yield of at least 80% 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.

The present invention discloses a method for preparing taurine. According to the method, ethylene oxide reacts with hydrosulphite to generate isethionate, after the isethionate and ammonia are subjected to an ammonolysis reaction under a microwave condition, ammonia removal is conducted to obtain a taurine salt solution, the taurine salt solution is converted into a taurine solution through acidification or ion exchange or ion membrane or heating, and taurine is extracted through concentration and crystallization. According to the present invention, the reaction time can be shortened, and the reaction temperature and pressure can be reduced, thereby achieving high yield and reducing energy consumption.

The present invention discloses a method for preparing taurine. According to the method, ethylene oxide reacts with hydrosulphite to generate isethionate, after the isethionate and ammonia are subjected to an ammonolysis reaction under a microwave condition, ammonia removal is conducted to obtain a taurine salt solution, the taurine salt solution is converted into a taurine solution through acidification or ion exchange or ion membrane or heating, and taurine is extracted through concentration and crystallization. According to the present invention, the reaction time can be shortened, and the reaction temperature and pressure can be reduced, thereby achieving high yield and reducing energy consumption.

The present invention provides a method for producing an aqueous tin methanesulfonate solution by dissolving tin (II) oxide in an aqueous methanesulfonic acid solution, wherein if A is the number of moles of the tin (II) oxide and B is the number of moles of the methanesulfonic acid, the value of B/2A is within the range of from 1.0 to 1.4. This method for dissolving tin (II) oxide into an aqueous methanesulfonic acid solution is able to achieve a high tin ion concentration.

The present invention provides a method for producing an aqueous tin methanesulfonate solution by dissolving tin (II) oxide in an aqueous methanesulfonic acid solution, wherein if A is the number of moles of the tin (II) oxide and B is the number of moles of the methanesulfonic acid, the value of B/2A is within the range of from 1.0 to 1.4. This method for dissolving tin (II) oxide into an aqueous methanesulfonic acid solution is able to achieve a high tin ion concentration.

The present invention provides a method for producing an aqueous tin methanesulfonate solution by dissolving tin (II) oxide in an aqueous methanesulfonic acid solution, wherein if A is the number of moles of the tin (II) oxide and B is the number of moles of the methanesulfonic acid, the value of B/2A is within the range of from 1.0 to 1.4. This method for dissolving tin (II) oxide into an aqueous methanesulfonic acid solution is able to achieve a high tin ion concentration.

Disclosed are compounds of general formula (I):

##STR00001##

and pharmaceutically acceptable salts thereof, formulations, methods and uses in, for example, the treatment of disease.

Provided is a catalyst for preparing high-purity taurine, and the catalyst is N,N-disubstituted aminoethanesulfonic acid and has a structure represented by Formula I, in which R.sup.1 and R.sup.2 are each independently selected from alkyl, alkenyl, alkynyl, alkoxy, benzyl, sulfhydryl, thioether group, aryl, heteroaryl, amino, amide, imide, cyano, aldehyde group, carbonyl, carboxyl, sulfonic acid group, or ester group. Also provided is a method for preparing high-purity taurine, which adds the catalyst in an ammonolysis step for preparing taurine, thereby having effects of high yield, inhibition of impurity production and a reduced amount of ammonia used, etc. The catalyst has advantages of low cost, stable physical properties, and easy separation from the product. The preparation method is simple to operate with easily available raw materials and high yield, and can be employed for industrial production. Moreover, the purity of the prepared taurine can be up to 98% or higher. ##STR00001##

Provided is a catalyst for preparing high-purity taurine, and the catalyst is N,N-disubstituted aminoethanesulfonic acid and has a structure represented by Formula I, in which R.sup.1 and R.sup.2 are each independently selected from alkyl, alkenyl, alkynyl, alkoxy, benzyl, sulfhydryl, thioether group, aryl, heteroaryl, amino, amide, imide, cyano, aldehyde group, carbonyl, carboxyl, sulfonic acid group, or ester group. Also provided is a method for preparing high-purity taurine, which adds the catalyst in an ammonolysis step for preparing taurine, thereby having effects of high yield, inhibition of impurity production and a reduced amount of ammonia used, etc. The catalyst has advantages of low cost, stable physical properties, and easy separation from the product. The preparation method is simple to operate with easily available raw materials and high yield, and can be employed for industrial production. Moreover, the purity of the prepared taurine can be up to 98% or higher. ##STR00001##