| abstract |
Water is conditioned by contacting it with a weak acid cation exchange resin based upon a crosslinked methacrylic acid copolymer structure in the alkali metal (or ammonium) form. The resin when exhausted may be regenerated by either a two-step acid/alkali technique or by a one-step technique using a citric or fumaric acid solution or a poly or hexamethaphosphate solution. Water by this method is substantially free of hardness ion, dissolved heavy metal ions and has a corrected pH between 7 and 9.5, preferably between 8 and 8.5. |