Process for preparing chelating agents
Abstract
Abstract A chelating agent having the formula WHEREIN; R is an alkyl group having about one to 20 carbon atoms, hydrogen, -CH2CH2OH, or -CH2COOM; and M is an alkali metal cation, is prepared by; (a) adjusting the pH of a first aqueous system consisting essentially of water and an amino acid having the formula OR AN ALKALI METAL SALT OF THE ACID TO ABOUT 6-10.5 TO FORM A SECOND AQUEOUS SYSTEM CONSISTING ESSENTIALLY OF THE ALKALI METAL SALT OF THE AMINO ACID DISSOLVED IN WATER, AND ADJUSTING THE TEMPERATURE OF THE SECOND AQUEOUS SYSTEM AT ABOUT 65*-105* C.; and (b) admixing epichlorohydrin with the second aqueous system while; (i) maintaining the pH of the resulting mixture at about 6-10.5; and (ii) maintaining the temperature of the resulting mixture at about 65*-105* C. for about 30-180 minutes to form a third aqueous system consisting essentially of an aqueous solution of the chelating agent.
Inventors
- 👤 Patricia M Scanlon
- 👤 Jon C Thunberg
Bibliographic Details
Claims Analysis
Total Claims: 5References Cited (Backward Citations)
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