abstract |
The present invention relates to a cyclic continuous process for the removal of boron ion from aqueous streams. An aqueous stream in contacted with an aqueous solution of a water-soluble organic polymeric chelant. The boron ion is absorbed and chelated. The separation of water and smaller molecules is accomplished by separation means such as ultrafiltration or dialysis. The concentrated aqueous solution is then treated with dilute aqueous mineral acid, followed by the released boron. The chelant is then recycled and reused. Preferred chelants are polymers having pendant N-alkylglucamine or derivative thereof or trihydroxyalkylamines or derivatives thereof. A preferred chelant is N-methylglucamine attached to a commercial FIBRABON 35 polymer using a -2-hydroxypropyl linkage. Additional preferred embodiments are those polymers having trihydroxymethyl amine in the pendant group attached to a FIBRABON 35 polymer backbone. The process is useful to remove toxic boron from agricultural water, industrial waters, waste-water sewage, oil well brine, and the like. |