Process for preparing soap-acyl isethionate compositions

A process for continuous production of a composition comprising alkali metal salts of C.sub.8 -C.sub.22 alkyl fatty acid and C.sub.8 -C.sub.22 acyl isethionate in a ratio of about 20:1 to 1:0.98, said process comprising the steps of:

• (i) forming an aqueous caustic solution comprising sodium hydroxide in an amount sufficient to neutralize a C.sub.8 -C.sub.22 alkyl fatty monocarboxylic acid and from 0 to 20% by weight of an alkali metal isethionate, said solution being maintained at a temperature from at least 180.degree. F. to about 200.degree. F. to obtain a hot solution;
• (ii) separately and simultaneously charging a first feed stream of said C.sub.8 -C.sub.22 alkyl fatty monocarboxylic acid and a second feed stream of said hot caustic solution into a mixing chamber to form said alkali metal C.sub.8 -C.sub.22 alkyl fatty monocarboxylic acid salt;
• and
• (iii) mixing said formed alkali metal C.sub.8 -C.sub.22 alkyl fatty monocarboxylic acid salt with said alkali metal C.sub.8 -C.sub.22 acyl isethionate salt to form said composition, and wherein said acyl isethionate salt is introduced to said mixing chamber as a slurry in said fatty monocarboxylic acid.

A process for the production of a composition comprising alkali metal salts of C.sub.8 -C.sub.22 alkyl fatty monocarboxylic acid and C.sub.8 -C.sub.22 acyl isethionate in a ratio of 20:1 to 1:0.98, said process comprising the steps of:

• (i) forming an aqueous caustic solution comprising sodium hydroxide in an amount sufficient to neutralize a C.sub.8 -C.sub.22 alkyl fatty monocarboxylic acid and from 0 to 20% by weight of an alkali metal isethionate, said solution being maintained at a temperature from at least 180.degree. F. to about 200.degree.F. to obtain a hot solution;
• (ii) charging said C.sub.8 -C.sub.22 alkyl fatty monocarboxylic acid to a reactor and agitating said fatty monocarboxylic acid under high speed mixing;
• (iii) slowly adding said hot caustic solution to said fatty monocarboxylic acid in said reactor;
• and
• (iv) feeding said acyl isethionate salt to said reactor at a time subsequent to the addition of said caustic solution in step (iii).

Process for continuous production of a composition comprising alkali metal salts of C.sub.8 -C.sub.22 alkyl fatty acid and C.sub.8 -C.sub.22 acyl isethionate in a ratio of about 20:1 to 1:0.98, said process comprising the steps of:

• (i) forming an aqueous caustic solution comprising sodium hydroxide in an amount sufficient to neutralize a C.sub.8 -C.sub.22 alkyl fatty monocarboxylic acid and from 0 to 20% by weight of an alkali metal isethionate, said solution being maintained at a temperature from at least 180.degree. F. to about 200.degree. F. to obtain a hot solution;
• (ii) separately and simultaneously charging a first feed stream of said C.sub.8 -C.sub.22 alkyl fatty monocarboxylic acid and a second feed stream of said hot caustic solution into a mixing chamber to form said alkali metal C.sub.8 -C.sub.22 alkyl fatty monocarboxylic acid salt;
• and
• (iii) mixing said formed alkali metal C.sub.8 -C.sub.22 alkyl fatty monocarboxylic acid salt with said alkali metal C.sub.8 -C.sub.22 acyl isethionate salt to form said composition, and wherein said acyl isethionate salt is introduced subsequent to step (ii).