Improvements in the treatment of base exchange bodies

摘要

In order to prevent discolouration of water softened thereby, base-exchange material containing humic acid is treated with a solution containing chromium combined as a base. A complex chromium humate is probably formed. The base-exchange material may be obtained by treating coal or lignite with sulphuric acid as described in Specification 450,574, [Group I]. Chromic sulphate, chloride and acetate and the chrome alums are mentioned as suitable salts for the chromium solution but solutions of chromates or dichromates may be used in presence of a reducing agent, such as sodium sulphite or bisulphite, so that chromium is obtained as a base in situ. The treatment may be hastened by heating. The base-exchange material may be subjected to a preliminary treatment with solution containing alkali metal ions.ALSO:In order to prevent discoloration of water softened thereby, base-exchange material containing humic acid is treated with a solution containing chromium combined as a base. A complex chromium humate is probably formed. The base-exchange material may be that obtained by treating coal or lignite with sulphuric acid as described in Specification 450,574. Chromic sulphate, chloride and acetate and the chrome alums are mentioned as suitable salts for the chromium solution, but solutions of chromates or dichromates may be used in presence of a reducing agent, such as sodium sulphite or bisulphite, so that the chromium is obtained as a base in situ. The treatment may be hastened by heating. The base-exchange material may be subjected to a preliminary treatment with solution containing alkali metal ions.