天然沸石降氟作用的初步探讨

为了探讨有关天然沸石降低水溶液中氟含量方面实际应用的可能性及其机理,笔者自1979年春到1982年冬断断续续开展了些试验。实验中也用雪硅钙石(建筑上加气砖废料)对笔者的观点作了进一步验证。

PRELIMINARY DISCUSSIONS ON REDUCING FLUORINE ANIONS IN SOLUTION BY USING NATURAL ZEOLITE

The phenomenon of reducing fluorine anions in solution by natural zeolite and its Ca-type zeolite originates from the ion exchange capability of zeolites. Owing to the microdissolution of trace calcium fluoride, it is difficult to reduce the trace fluorine anions from potable water by using natural zeolites or Ca-type zeolites.If Ca-type clinoptilolite heat-treated at a certain temperature is soaked in the dilute sulphuric acid beforehand, the complexing between zeolite and SO₄^2- occurs first, and then used for removing fluorine anions, as a result, the capability of removing fluorine will be improved.The excess fluorine anions in potable water can be removed by using zeolite-aluminium salt method. The essence is a reaction of aluminium salt and its hydrolyzate fixed on zeolite carrie with fluorine.Fluorine anions can also be removed from water by using the fragments of air entraining porous brick carrying aluminium salt, which provides a strong evidence for the mechanism of removing fluorine by using zeolite-aluminium salt.