In order to realize resource utilization of industrial tungsten residue and treatment of ammonium wastewater with the solid waste, a porous ceramsite was prepared with the main raw materials of diatomite and tungsten residue. The adsorption behavior of ammonium in synthetic leachate of ionic rare earth mining area soil by the ceramsite was investigated. The results show that the surface of the newly-developed ceramsite is rough and porous. There are lots of pores across the ceramsite from inner to outside. MnFe2O4is one of the main components of the ceramsite. In pH range of the test, when pH is 5.68, the ammonium adsorption capacity by the ceramsite reaches the maximum. With the increase of temperature, the adsorption capacity decreases. The saturated adsorption capacity is 1.60 mg/g at 303 K, 0.5 g dosage of the ceramsite. The isothermal adsorption fits the Langmuir and Freundlich models better; and the adsorption process follows the pseudo-second kinetic equation. Accordingly, it can be deduced that for real leachate from ionic rare earth mining area soil, the ceramsite can be used to remove ammonium from it, the removal process is efficiently; with the decrease of temperature, the adsorption capacity would increase; when pH is about 5.68, the ammonium adsorption capacity by the ceramsite will reach the maximum.%为实现工业钨渣资源化利用以及"以废治废"的目标,以硅藻土和工业钨渣为主要原料制备多孔陶粒,研究陶粒对离子型稀土矿区土壤淋滤液中氨氮的吸附去除规律.结果表明:近球状的硅藻土?钨渣基陶粒表面粗糙多孔,内部有大量贯穿孔洞与表面相连通,陶粒的主要物相组成含有MnFe2O4;在试验溶液初始pH范围内,当pH=5.68左右时,陶粒对溶液中氨氮的吸附量达最大;随着试验温度的升高,陶粒对氨氮的吸附去除量降低;在温度为303 K、陶粒投加量为0.5 g的条件下,陶粒对氨氮的饱和吸附量为1.60 mg/g;陶粒对氨氮的等温吸附符合Langmuir模型和Freundlich模型,吸附动力学符合准二级动力学模型;据此可推断,对于实际稀土矿区土壤的氨氮淋滤液,所制备陶粒可有效去除其中氨氮,吸附去除过程易于进行,且随温度的降低,其对氨氮的去除量增大;在实际淋滤液的pH值存在范围内,当pH=5.68左右时,陶粒对淋滤液中氨氮的吸附去除量将达到最大值.
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