Purificn. of water supply for domestic consumption - by treatment with mixt. of nitrate-selective anion exchanger and weak acid cation exchanger to give germ-free, low nitrate, partially desalted water

Process for producing a disinfected, low nitrate, partially desalted drinking water for domestic use comprises treating the available unrefined water with an ion exchanger mixt. consisting of at least 30% of a nitrate selective anion exchanger whose functional gps. are charged with 70-100 % HCO3(-) ions, and a weak acid cation exchanger in the H(+) form. The ion exchanger mixt. may also include 10-20 % of a strong acid cation exchanger in the H(+) or Na(+) form and a nitrate selective anion exchanger in the Cl(-) or SO4(2-) form. USE/ADVANTAGE - For preparing relatively small amts. of purified water for domestic consumption starting with normal supply water. The process can be carried out using a simple appts. which is generally in the form of a filter through which the water flows from a reservoir vessel into a receiver such as a bottle. After treatment the water is germ-free and has a low nitrate content and reduced salt content. Only small amts. of the ion exchanger mixt. are involved and pollution of the environment is very low.