Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, Hong Kong, China.
Chemosphere. 2010 Jun;80(4):375-80. doi: 10.1016/j.chemosphere.2010.04.048. Epub 2010 May 15.
This study aims to evaluate the feasibility of stabilizing copper-laden sludge by the application of alumina-based ceramic products. The processing temperature, material leaching behaviour, and the effect of detoxification were investigated in detail. CuO was used to simulate the copper-laden sludge and X-ray Diffraction was performed to monitor the incorporation of copper into the copper aluminate spinel (CuAl(2)O(4)) phase in ceramic products. It was found that the development of CuAl(2)O(4) increased with elevating temperatures up to and including 1000 degrees C in the 3h short-sintering scheme. When the sintering temperature went above 1000 degrees C, the CuAl(2)O(4) phase began to decompose due to the high temperature transformation to CuAlO(2). The leachability and leaching behaviour of CuO and CuAl(2)O(4) were compared by usage of a prolonged leaching test modified from US EPA's toxicity characteristic leaching procedure. The leaching results show that CuAl(2)O(4) is superior to CuO for the purpose of copper immobilization over longer leaching periods. Furthermore, the detoxification effect of CuAl(2)O(4) was tested through bacterial adhesion with Escherichia coli K12, and the comparison of bacterial adhesion on CuO and CuAl(2)O(4) surfaces shows the beneficial detoxification effect in connection with the formation of the CuAl(2)O(4) spinel. This study demonstrates the feasibility of transforming copper-laden sludge into the spinel phase by using readily available and inexpensive ceramic materials, and achieving a successful reduction of metal mobility and toxicity.
本研究旨在评估通过氧化铝基陶瓷产品稳定含铜污泥的可行性。详细研究了处理温度、材料浸出行为以及解毒效果。使用氧化铜模拟含铜污泥，并通过 X 射线衍射监测铜在陶瓷产品中掺入铜铝尖晶石（CuAl(2)O(4)）相的情况。结果表明，在 3 小时短烧方案中，随着温度升高至 1000°C 及以上，CuAl(2)O(4)的生成量增加。当烧结温度超过 1000°C 时，由于高温向 CuAlO(2)的转变，CuAl(2)O(4)相开始分解。通过使用美国环保署（EPA）毒性特征浸出程序修改后的延长浸出试验比较了 CuO 和 CuAl(2)O(4)的浸出率和浸出行为。浸出结果表明，在较长的浸出时间内，CuAl(2)O(4)比 CuO 更有利于铜的固定。此外，通过大肠杆菌 K12 的细菌黏附测试了 CuAl(2)O(4)的解毒效果，并比较了 CuO 和 CuAl(2)O(4)表面上的细菌黏附情况，表明形成 CuAl(2)O(4)尖晶石具有有益的解毒效果。本研究表明，通过使用易得且廉价的陶瓷材料将含铜污泥转化为尖晶石相是可行的，并成功降低了金属的迁移性和毒性。
