Process for selective removal of toxic ions from water

#Drinking water must be free of highly toxic ions such as the anions bromide, the arsenates, selenate, cyanide, etc., and the cations of manganese and chromium, lead, copper, mercury, etc. Ion exchange resins have frequently been used to purify drinking water. In some cases, relatively selective ion exchange systems have been disclosed in the prior art.

#For example, Solt et al., U.S. Pat. No. 5,086,185, discloses a method of selectively removing nitrate ions from water containing high concentrations of sulfate ions.

#Selective removal of nitrate from water containing both nitrates and sulfates has also been disclosed by Gutt, U.S. Pat. No. 4,479,877.

#An exemplary water to be treated had the following anion content:

#Bromide=1.0 ppm

#Nitrate=0.107 meq/l Trace