Selective adsorption and separation of chromium (VI) on the magnetic iron-nickel oxide from waste nickel liquid.
Selective adsorption and separation of chromium (VI) on the magnetic iron-nickel oxide from waste nickel liquid.
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DOI：
10.1016/j.jhazmat.2008.09.016
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发表时间：
2009-05
影响因子：
13.6
通讯作者：
Linsen Wei;Gang Yang;Ren Wang;Wei Ma
中科院分区：
文献类型：
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作者：
Linsen Wei;Gang Yang;Ren Wang;Wei Ma
研究了磁性铁镍氧化物对含铬镍废水中六价铬的选择性吸附。采用共沉淀法合成的铁镍磁性粒子作为吸附剂去除六价铬离子。用Langmuir、Freundlich等温式和Dubinin-Kaganer-Radushkevich(DKR)方程对模拟废水中铬(VI)-镍(II)二元体系的吸附特性进行了评价。用能谱和FT-IR对吸附前后的吸附剂进行了测试。结果表明，磷酸根离子对铬(VI)的吸收作用明显，其他阴离子的吸收作用不明显。在pH为5.00±0.02时，六价铬的最大吸附容量约为30 mg/g，且随体系总溶解物质(TDS)的增加而减小。在不同的TDS条件下，由DKR方程得到的吸附能E约为10.310-21.321kJ/m o l。再生结果表明，铁镍氧化物具有良好的再利用性能，六价铬得到回收利用。在TDS<200 mg/L的条件下，吸附机理以离子交换为主，表面配位起主要作用。
The selective adsorption of Cr (VI) from the wastewater of Cr (VI)–Ni (II) by magnetically iron–nickel oxide was investigated in this study. Synthetic iron–nickel oxide magnetic particles in the co-sedimentation method were used as adsorbent to remove hexavalent chromium ions. The characteristic of adsorption was evaluated by Langmuir, Freundlich isotherm and Dubinin–Kaganer–Radushkevich (DKR) equations in the simulation wastewater of Cr (VI)–Ni (II) bi-system. The energy spectra and FT-IR analysis were used to test adsorbent before and after adsorption. The obtained results suggest that the uptake of chromium (VI) effect is obvious from phosphate anions and that from others is unobvious. The maximum adsorption capacity of hexavalent chromium is about 30mg/g at pH 5.00±0.02, and it was reduced by increasing the total dissolved substance (TDS) of system. Adsorption energies E are about 10.310–21.321kJ/mol which were obtained from DKR equation in difference TDS conditions. The regeneration shows that the iron–nickel oxide has good reuse performance and the hexavalent chromium was recycled. The major adsorption mechanism proposed was the ions exchange; however the surface coordination was a main role in the condition of TDS less than 200mg/L.