METHOD OF CATION EXCHANGE RESIN REGENERATION USING HIGHER CONCENTRATION OF SULFURIC ACID FOR STRIPPING AND PRECIPITATING ADSORBED MAGNESIUM

摘要

Adsorbed magnesium is removed from a cation exchange resin by elution with 20 to 70% sulfuric acid as increments of the loaded resin move upwardly in a stripping column, the regenerated resin being removed at the top of the column and the sulfuric acid of reduced concentration with the eluted magnesium is removed from the lower portion of the column. The sulfuric acid concentrations are controlled so that the regenerating solution can be formed from commercial concentrations of sulfuric acid without undue dilution, and so that magnesium can be precipitated from the eluting solution by increasing the sulfuric acid concentration without adding a large amount of commercial concentration acid. The amount of dilute sulfuric acid produced as a waste material is kept to a minimum, while the principal sulfuric acid by-produkt has a usefully high concentration, such as may be employed for treatment of phosphate rock.