Patent ID: 7550632

Claim:
A method comprising: (a) providing a composition comprising triethanolamine; and (b) contacting the composition with an acid component and a basic component; wherein the acid component comprises an acid selected from the group consisting of phosphorous acid, hypophosphorous acid and mixtures thereof; and wherein the basic component comprises a compound selected from the group consisting of alkali metal hydroxides, alkaline earth metal hydroxides, ammonium hydroxides according to general formula (I), and mixtures thereof: [R 1 R 2 R 3 (2-hydroxyethyl)ammonium] hydroxide (I) wherein R 1 , R 2 and R 3 each independently represents a C 1-30 alkyl or a C 2-10 hydroxyalkyl; with the proviso that where the basic component comprises an alkali metal hydroxide, the molar ratio of acid component: basic component is 1:0.1 to 1:1, and where the basic component comprises an alkaline earth metal hydroxide, the molar ratio of acid component: basic component is 1:0.05 to 1:0.5.