Research On Removal Of Arsenic In Drinking Water By Modified Zeolite

With the continuous development of society, the continuous improvement of living standards, people living for health requirements in drinking water become more and more high, in our country and even the world, local arsenic poisoning has an influence range, the traditional arsenic treatment method in drinking water is hard to meet the requirements of the reality, so research and development of a new type of arsenic agent for drinking water is very important. Natural zeolite has rich reserves and low price in china, since it has large surface area, so it often used as water treatment adsorbent, but the adsorption performance of natural zeolite is limited, and scientific research personnel pay more attention the method that through its modification to improve its adsorption at home and abroad.This topic study the modified zeolite as adsorbent to the arsenic-exceedding removal efficiency of raw water, including static and dynamic experiment two parts, the specific contents include the following:zeolite modification methods and all kinds of different modification methods of modification conditions of the best choice, and selected a kind of modified zeolite for arsenic removal to good effect, good competitive performance, strong anti-interference ability as the best modified zeolite (manganese-modified-zeolite); Research on manganese-modified zeolite removal performance of arsenic in the simulation water, and discusses their removal mechanism; Research manganese modified zeolite in addition to the influence factors of arsenic removal(including temperature, pH, arsenic initial concentration); Research arsenic removal effect and the influence factors (filter layer thickness, filter speed, arsenic initial concentration) for manganese modified zeolite packed column simulation through dynamic experiment in arsenic-exceedding raw water, and analyzes its effectiveness and feasibility.Static experiment results show that the manganese-modified zeolite has the best arsenic removal efficiency, magnesium-modified zeolite is worse, far higher than not modified zeolite to arsenic removal. Manganese modified zeolite best modification conditions for:Zeolite process gelation reaction with KMnO4and MnSO4solution for 40min,aging for2.0days,calcining for2.Oh at450℃,4, zeolite and MnO2weight ratio is5. Natural zeolite, magnesium modified zeolite and manganese modified zeolite three zeolite is effected badly for removing arsenic in drinking water by competition ions, interference and organic ions, manganese modified zeolite has the strong anti-jamming ability, strong competitive performance, and the best the removal arsenic efficiency. Through the curve fitting for adsorption of arsenic by the manganese modified zeolite in water, the result is the adsorption of arsenic to accord with the Langmuir isothermal adsorption model, manganese-modified zeolite adsorption belongs to the single molecule layer absorption on arsenic removal process from water.Adsorption kinetic process of arsenic removal by manganese-modified zeolite can better comply with secondary dynamic equation, the fitting correlation coefficient(R2) is0.9973.Dynamic experimental results show that the manganese modified zeolite filter in simulation arsenic-exceedding water column has the better arsenic removal efficiency at100cm filter layer thickness,5cm filter inner diameter column,100μg/L arsenic concentration from simulation water sample,4mL/min filter speed. In practical production, the selection of suitable filter layer thickness, controlling the filter speed, arsenic removal by the manganese modified zeolite from simulation arsenic-exceedding water column is effective and feasible.