(1. 中南大學(xué) 冶金與環(huán)境學(xué)院，長沙 410083； 2. 江西理工大學(xué) 冶金與化學(xué)工程學(xué)院，贛州 341000)
摘 要: 為實現(xiàn)工業(yè)鎢渣資源化利用以及“以廢治廢”的目標，以硅藻土和工業(yè)鎢渣為主要原料制備多孔陶粒，研究陶粒對離子型稀土礦區(qū)土壤淋濾液中氨氮的吸附去除規(guī)律。結(jié)果表明：近球狀的硅藻土-鎢渣基陶粒表面粗糙多孔，內(nèi)部有大量貫穿孔洞與表面相連通，陶粒的主要物相組成含有MnFe2O4；在試驗溶液初始pH范圍內(nèi)，當pH=5.68左右時，陶粒對溶液中氨氮的吸附量達最大；隨著試驗溫度的升高，陶粒對氨氮的吸附去除量降低；在溫度為303 K、陶粒投加量為0.5 g的條件下，陶粒對氨氮的飽和吸附量為1.60 mg/g；陶粒對氨氮的等溫吸附符合Langmuir模型和Freundlich模型，吸附動力學(xué)符合準二級動力學(xué)模型；據(jù)此可推斷，對于實際稀土礦區(qū)土壤的氨氮淋濾液，所制備陶粒可有效去除其中氨氮，吸附去除過程易于進行，且隨溫度的降低，其對氨氮的去除量增大；在實際淋濾液的pH值存在范圍內(nèi)，當pH=5.68左右時，陶粒對淋濾液中氨氮的吸附去除量將達到最大值。
關(guān)鍵字: 離子型稀土礦區(qū)；多孔陶粒；鎢渣；土壤氨氮淋濾液；吸附
（1. School of Metallurgy and Environment, Central South University, Changsha 410083, China; 2. School of Metallurgical and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China）
Abstract: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. MnFe2O4 is 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.
Key words: ionic rare earth mining area; porous ceramsite; tungsten residue; soil ammonium leachate; adsorption
