| Fluorine is an essential element for human health. The presence of fluoride within permissible limits is beneficial for the production and maintenance of healthy bones and teeth, while excessive intake of fluoride causes dental or skeletal fluorosis which is a chronic disease. Drinking water is the main source of fluoride in human body. In China there are about 70 million people suffering endemic disease caused by extra intake of fluoride from drinking water. It is of great importance to study the methods of fluoride removal from water.Aiming at the above problem, a study on activation method and defluorination performance of natural zeolite has been carried out.In this paper, we discussed firstly the formation and distribution of high fluorine water as well as its effect on human, then current methods used to remove fluoride from water are analyzed and compared. On this condition, a novel and efficient absorbent to remove fluoride from water has been studied.In the first part of the experiments, activation methods on natural zeolite have been investigated. A new defluoridation material can be obtained by such ways: first, natural zeolite was roasted at 450℃in a muffle furnace for 2h, then impregnated with 10% H2SO4 solution for 24h, the treated zeolite was then washed by distilled water and dried, in the end, impregnated with 1.0mol/L MgSO4 solution for 24h, washed and dried enough. The results showed that the material could effectively remove fluoride from water. The absorption capacity of activated zeolite is about 3.97 times of that of inactivated one.In this paper, fluoride removal using activated zeolite was studied by static and dynamic experiment. The factors affecting the adsorption capacity of activated zeolite and the adsorption isotherm as well as the rate of the adsorption and the condition of regeneration were also studied.
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