The present disclosure relates to an additive used in a methionine preparation process, and a methionine preparation method. The additive provided by the present disclosure is a mixture containing components A, B, and C; component A has a structure represented by the following general formula (1); component B has a structure represented by the following general formula (2); component C is silicone oil; RCON(CH.sub.3)CH.sub.2CH.sub.2SO.sub.3Na (1). The methionine preparation method provided in the present invention comprises subjecting methionine to crystallization and/or recrystallization in the presence of the additive provided by the present disclosure. The additive provided by the present disclosure results in uniform emulsification, has good stability, can be used stably for a long time, and is suitable for a continuous crystallization process. The prepared methionine crystal has a good crystal form, a large bulk density, and good flowability. In addition, according to the methionine preparation method of the present disclosure, a crystallization system can operate continuously and stably for a long time without obvious foaming, and the crystallization process of the methionine product can proceed smoothly.

##STR00001##

The present disclosure relates to an additive used in a methionine preparation process, and a methionine preparation method. The additive provided by the present disclosure is a mixture containing components A, B, and C; component A has a structure represented by the following general formula (1); component B has a structure represented by the following general formula (2); component C is silicone oil; RCON(CH.sub.3)CH.sub.2CH.sub.2SO.sub.3Na (1). The methionine preparation method provided in the present invention comprises subjecting methionine to crystallization and/or recrystallization in the presence of the additive provided by the present disclosure. The additive provided by the present disclosure results in uniform emulsification, has good stability, can be used stably for a long time, and is suitable for a continuous crystallization process. The prepared methionine crystal has a good crystal form, a large bulk density, and good flowability. In addition, according to the methionine preparation method of the present disclosure, a crystallization system can operate continuously and stably for a long time without obvious foaming, and the crystallization process of the methionine product can proceed smoothly.

##STR00001##

The present disclosure relates to an additive used in a methionine preparation process, and a methionine preparation method. The additive provided by the present disclosure is a mixture containing components A, B, and C; component A has a structure represented by the following general formula (1); component B has a structure represented by the following general formula (2); component C is silicone oil; RCON(CH.sub.3)CH.sub.2CH.sub.2SO.sub.3Na (1). The methionine preparation method provided in the present invention comprises subjecting methionine to crystallization and/or recrystallization in the presence of the additive provided by the present disclosure. The additive provided by the present disclosure results in uniform emulsification, has good stability, can be used stably for a long time, and is suitable for a continuous crystallization process. The prepared methionine crystal has a good crystal form, a large bulk density, and good flowability. In addition, according to the methionine preparation method of the present disclosure, a crystallization system can operate continuously and stably for a long time without obvious foaming, and the crystallization process of the methionine product can proceed smoothly.

##STR00001##

A chemical compound of formula (I), ##STR00001##
and specific compositions including 3-methylthiopropionaldehyde, 3-methylthiopropane-1,1-diol, a compound of formula I and water, and processes for producing same and also the use of same may be used for the production of 2-hydroxy-4-(methylthio)butyronitrile, methionine hydantoin, methionine. Protected forms may be used for the storage and/or transport of 3-methylthiopropionaldehyde.

A chemical compound of formula (I), ##STR00001##
and specific compositions including 3-methylthiopropionaldehyde, 3-methylthiopropane-1,1-diol, a compound of formula I and water, and processes for producing same and also the use of same may be used for the production of 2-hydroxy-4-(methylthio)butyronitrile, methionine hydantoin, methionine. Protected forms may be used for the storage and/or transport of 3-methylthiopropionaldehyde.

The present disclosure provides methods and compositions for inhibiting degradation of dimethyl trisulfide (DMTS) in solution. Concentrate compositions include DMTS and polar inorganic or organic solvent. The compositions can be stored in containers for at least 2 weeks at 54° C. or at least one year at room temperature and less than 50% of the DMTS degrades. The concentrate compositions can be diluted for use and combined with other components to form various solutions.

The present disclosure provides methods and compositions for inhibiting degradation of dimethyl trisulfide (DMTS) in solution. Concentrate compositions include DMTS and polar inorganic or organic solvent. The compositions can be stored in containers for at least 2 weeks at 54° C. or at least one year at room temperature and less than 50% of the DMTS degrades. The concentrate compositions can be diluted for use and combined with other components to form various solutions.

The invention concerns a method for treatment of a stream of mixed compounds (4a) obtained from a process (3) comprising decomposition and/or conversion of a wood or pulp material, the method comprising: feeding the stream (4a-4e) through a processing arrangement (2) comprising one or more treatment units (10, 20, 30, 40, 50) arranged to separate at least a first compound from other compounds in the stream and form a first product flow (4f) containing the first compound, wherein the one or more treatment units comprises at least a first primary separation unit (20) arranged to separate one or more compounds other than the first compound from the stream; and feeding the compounds separated from the first compound in the first primary separation unit (20) to a first auxiliary separation unit (21) so as to separate a second compound from at least one of the other compounds separated from the first compound in the first primary separation unit (20) and thereby increase the purity of said second compound and form a second product flow (22, 23) in the form of a purified second compound and/or a purified derivative of the second compound, wherein the second compound is dimethyl sulfide (DMS, CH3—S—CH3), methyl mercaptan (CH3—S—H) or acetone (CH3—CO—CH3).

The invention concerns a method for treatment of a stream of mixed compounds (4a) obtained from a process (3) comprising decomposition and/or conversion of a wood or pulp material, the method comprising: feeding the stream (4a-4e) through a processing arrangement (2) comprising one or more treatment units (10, 20, 30, 40, 50) arranged to separate at least a first compound from other compounds in the stream and form a first product flow (4f) containing the first compound, wherein the one or more treatment units comprises at least a first primary separation unit (20) arranged to separate one or more compounds other than the first compound from the stream; and feeding the compounds separated from the first compound in the first primary separation unit (20) to a first auxiliary separation unit (21) so as to separate a second compound from at least one of the other compounds separated from the first compound in the first primary separation unit (20) and thereby increase the purity of said second compound and form a second product flow (22, 23) in the form of a purified second compound and/or a purified derivative of the second compound, wherein the second compound is dimethyl sulfide (DMS, CH3—S—CH3), methyl mercaptan (CH3—S—H) or acetone (CH3—CO—CH3).

The present invention relates to a method of carrying out an organic reaction in aqueous solution in the presence of a hydroxyalkyl(alkyl)cellulose or an alkylcellulose.