Stabilization and phase transformation of CuFe2O4 sintered from simulated copper-laden sludge

JOURNAL OF HAZARDOUS MATERIALS

卷:190

Article

Li, Nien-Hsun¹  Lo, Shang-Lain¹  Hu, Ching-Yao²  Hsieh, Ching-Hong¹  Chen, Ching-Lung¹ 

[1] Natl Taiwan Univ, Grad Inst Environm Engn, Taipei 106, Taiwan

[2] Taipei Med Univ, Sch Publ Hlth, Taipei 110, Taiwan

关键词: Copper;    Sludge;    Spinel;    CuFe2O4;    Stabilization;   

DOI  :  10.1016/j.jhazmat.2011.03.089

来源: Elsevier

【 摘 要 】

The feasibility of stabilizing copper-laden sludge by high-temperature CuFe2O4 ferritization process is investigated with different sintering temperature, and the prolonged leaching test. The thermal behavior, structural morphology, phase composition, and phase transformation of the stabilized sludge were investigated by using thermal gravimetry-differential scanning calorimetry, scanning electron microscopy and X-ray diffraction. The leaching behavior of the stabilized sludge under acidic environment was evaluated by modified Toxicity Characteristic Leaching Procedure (TCLP). The results indicated that CuFe2O4 could be effectively formed at around 800 degrees C by the iron oxide precursor with a 3 h of short sintering. The transformation was discovered on crystallographic spinel structures: the low-temperature (800-900 degrees C) tetragonal phase (t-CuFe2O4) and the high-temperature (similar to 1000 degrees C) cubic phase (c-CuFe2O4). At higher temperatures (similar to 1100 degrees C), the formation of cuprous ferrite delafossite phase (CuFeO2) from the dissociation of CuFe2O4 was also noticed. Both CuFe2O4 spinel and CuFeO2 delafossite phase have a better intrinsic resistance to acidic environment when compared to that of CuO phase by the modified TCLP test. The sintering strategy designed for copper-laden sludge is proven to be beneficial in stabilizing copper. (C) 2011 Elsevier B.V. All rights reserved.

【 授权许可】

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