There is disclosed a cyclic process for producing taurine from monoethanolamine comprising the steps of: (a) recovering monoethanolamine sulfate from an aqueous mother liquor solution; (b) reacting the monoethanolamine sulfate with sulfuric acid to form an aqueous solution comprised of monoethanolamine bisulfate; (c) heating the aqueous solution comprised of the monoethanolamine sulfate and optionally added monoethanolamine sulfate to yield 2-aminoethyl hydrogen sulfate ester; and (d) reacting the ester with ammonium sulfite or an alkali sulfite to yield taurine.

There is disclosed a cyclic process for producing taurine from monoethanolamine comprising the steps of: (a) recovering monoethanolamine sulfate from an aqueous mother liquor solution; (b) reacting the monoethanolamine sulfate with sulfuric acid to form an aqueous solution comprised of monoethanolamine bisulfate; (c) heating the aqueous solution comprised of the monoethanolamine sulfate and optionally added monoethanolamine sulfate to yield 2-aminoethyl hydrogen sulfate ester; and (d) reacting the ester with ammonium sulfite or an alkali sulfite to yield taurine.

There is disclosed a cyclic process for producing taurine from monoethanolamine comprising the steps of: (a) recovering monoethanolamine sulfate from an aqueous mother liquor solution; (b) reacting the monoethanolamine sulfate with sulfuric acid to form an aqueous solution comprised of monoethanolamine bisulfate; (c) heating the aqueous solution comprised of the monoethanolamine sulfate and optionally added monoethanolamine sulfate to yield 2-aminoethyl hydrogen sulfate ester; and (d) reacting the ester with ammonium sulfite or an alkali sulfite to yield taurine.

The present disclosure is directed to provide a vinylsulfonic anhydride which is useful as a synthetic intermediate for synthesis of a fluorinated monomer. It is also directed to efficiently produce the vinylsulfonic anhydride. It is further directed to efficiently produce a fluorinated monomer using the vinylsulfonic anhydride. A vinylsulfonic anhydride of the present disclosure is expressed by the general formula (1). Further, a process for producing a vinylsulfonic anhydride of the present disclosure includes making a vinylsulfonic acid compound represented by the general formula (2) come in contact and be mixed with an anhydridization agent. Further, a process for producing a vinylsulfonyl fluoride of the present disclosure includes a step (b) of making a vinylsulfonic anhydride represented by the general formula (1) come in contact and be mixed with a fluorinating agent to prepare a reaction mixture including a vinylsulfonyl fluoride represented by the general formula (3) and a vinylsulfonic acid compound represented by the general formula (2).

The present disclosure is directed to provide a vinylsulfonic anhydride which is useful as a synthetic intermediate for synthesis of a fluorinated monomer. It is also directed to efficiently produce the vinylsulfonic anhydride. It is further directed to efficiently produce a fluorinated monomer using the vinylsulfonic anhydride. A vinylsulfonic anhydride of the present disclosure is expressed by the general formula (1). Further, a process for producing a vinylsulfonic anhydride of the present disclosure includes making a vinylsulfonic acid compound represented by the general formula (2) come in contact and be mixed with an anhydridization agent. Further, a process for producing a vinylsulfonyl fluoride of the present disclosure includes a step (b) of making a vinylsulfonic anhydride represented by the general formula (1) come in contact and be mixed with a fluorinating agent to prepare a reaction mixture including a vinylsulfonyl fluoride represented by the general formula (3) and a vinylsulfonic acid compound represented by the general formula (2).

There is disclosed a process for preparing taurine from alkali isethionate by reacting alkali taurinates in the solution of ammonolysis reaction of alkali isethionate with ammonium bisulfite or ammonium sulfite to obtain taurine and to regenerate alkali bisulfite or alkali sulfite, which is used to react with ethylene oxide to afford alkali isethionate.

There is disclosed a process for preparing taurine from alkali isethionate by reacting alkali taurinates in the solution of ammonolysis reaction of alkali isethionate with ammonium bisulfite or ammonium sulfite to obtain taurine and to regenerate alkali bisulfite or alkali sulfite, which is used to react with ethylene oxide to afford alkali isethionate.

There is disclosed a process for preparing taurine from alkali isethionate by reacting alkali taurinates in the solution of ammonolysis reaction of alkali isethionate with ammonium bisulfite or ammonium sulfite to obtain taurine and to regenerate alkali bisulfite or alkali sulfite, which is used to react with ethylene oxide to afford alkali isethionate.

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.