Process for preparing chelating agents
Abstract
Abstract A CHELATING AGENT HAVING THE FORMULA R-N(-CH2-COO-M)-CH2-CH(-OH)-CH2-N(-R)-CH2-COO-M WHEREIN; R IS AN ALKYL GROUP HAVING ABOUT 1-20 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 R-NH-CH2-COOH 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
- 👤 P Scanlon
- 👤 J Thunberg
Bibliographic Details
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