METHOD FOR PRODUCING CHELATING AGENT MIXTURE, CHELATING AGENT MIXTURE AND ITS APPLICATION METHODS Russian patent published in 2021 - IPC C07C227/08 C07C227/16 C07C229/12 C07C229/24 D21C9/10 

FIELD: chemistry.

SUBSTANCE: invention relates to a method for producing a chelating agent mixture containing a compound of the formula (I), in which at least one of radicals R₁, R₂ and R₃ is a group of succinic acid or its salt and at least one of radicals R₁, R₂ and R₃ is a carboxymethyl or 1-carboxyethyl group or its salt. The method includes the reaction of maleic acid or its salt with diethanolamine under alkaline conditions in the presence of a lanthanide catalyst to form at least one compound having the general formula (I), in which at least one of radicals R₁, R₂ and R₃ is a group of succinic acid or its salt. Upon subsequent addition, 2-halocarboxylic acid or its salt reacts with non-reacted diethanolamine and/or with intermediate compounds containing hydroxyl groups or secondary amino groups to form a mixture containing compounds having the general formula (I), in which at least one of radicals R₁, R₂ and R₃ is a group of succinic acid or its salt and at least one of radicals R₁, R₂ and R₃ is a carboxymethyl or 1-carboxyethyl group or its salt. The invention also relates to a chelating agent mixture and methods for chelating metals and bleaching fibrous mass using the specified mixture.

EFFECT: proposed method makes it possible to effectively obtain chelating agent mixtures in situ in the same reaction mixture.

15 cl, 1 dwg, 2 tbl, 2 ex