mFe/nCu的制备及其去除制革废水中有机络合态Cr(III)的原理和方法

One of the key technical difficulties in the sustainable development of tannery industry is that the effluent chromium of tannery waste can not meet the discharge standard. The chromium is difficult to removal thoroughly because they are in the form of complexation, and the complexation are organics (i.e., M≡Cr(III)). According to the exploratory study, by improving the distribution of copper on the surface of micro-scale iron (mFe), the M≡Cr(III) removal efficiency in aqueous solution by Fe/Cu bimetallic particles is obviously improved. Therefore, this project intends to prepare a novel mFe/nCu micro-electrolytic material, which is prepared by using copper complexes to form nano-sacle copper (nCu) on the iron base. What’s more, the removal of M≡Cr(III) in the tannery effluent is studied by the mFe/nCu reduction system under anaerobic condition. First of all, explore the optimization of mFe/nCu preparation, performance measurement and the mechanism of removing M≡Cr(III). Meanwhile, the method of transformation of M≡Cr(III) to simple Cr(III) ions and removing via sedimentation process finally would be achieved by mFe/nCu reduction system. In addition, the effect of multiple organic ligands on removal of M≡Cr(III) in mFe/nCu system would be studied, and the efficient removal method of organic complex chromium in tannery wastewater would be established. Finally, evaluate the stability of mFe/nCu bimetallic material, this would provide support of data, scientific principles and method for the application of the material in tannery wastewater treatment.

制革废水中铬含量难以达标排放，一直是制革行业可持续发展急需解决的核心技术难题之一。该废水中难去除的铬主要以有机络合态（M≡Cr(III)）的形式存在。申请人探索性实验研究发现，通过一定的技术手段改善铜在微米级铁基表面的分布，可以大幅度提高铁铜双金属对水溶液中M≡Cr(III)的去除率。因此，本项目拟通过用络合态的铜代替简单离子态的铜制备新型mFe/nCu材料，用厌氧条件下的还原体系进行制革废水中M≡Cr(III)的去除研究。探索mFe/nCu制备工艺的优化、性能的表征及其去除M≡Cr(III)的机理，提出该体系中M≡Cr(III)向Cr(III)离子转变并最终沉淀去除的方法；研究制革废水中多种有机配体共存对mFe/nCu去除M≡Cr(III)的影响，建立制革废水中铬的高效去除方法；评估mFe/nCu材料的循环使用稳定性，为该材料在制革废水处理的应用提供数据、科学原理和方法支撑。

皮革工业是我国轻工行业的支柱产业之一，在我国国民经济建设和出口创汇中正发挥着越来越重要的作用，但同时皮革产业也带来了不容忽视的环境问题。尤其是制革行业使用较多的铬鞣法，产生的废水中含有生物法难以去除的有机络合态铬。本项目展开了基于微米级铁基材料的高级氧化法去除水中有机络合态铬。为实现该目标，制备了新型微米级铁铜双金属，通过调控铜的形态及其他制备参数，实现了铁基表面纳米级零价铜的离散分布，使得铁铜双金属的活性在循环使用5次后仍高于普通新制备的铁铜双金属。该新型铁铜双金属由于其显著的活性已授权国家发明专利。且由于铁和铜直接的电势差可促进铁释放电子，新型铁铜双金属的pH使用范围也从酸性调节拓宽到中性条件，该发现为微米级铁基材料的应用奠定了坚实的基础，也可解决铁基材料在使用时需要加入大量的酸而带来的酸雾和铁泥量过大的问题。考虑到制革废水中含油量较高、成分非常复杂，故将制备的新型铁铜双金属材料在成分较为简单的弹药起爆药废水进行中试验证（处理量为1 t/d），在调整出较理想的运行参数后，开展了放大试验，每天处理废水量约为12-20 t/d。铁铜双金属处理出水进入到传统A2O工艺进行生物处理，出水稳定达到行业排放标准，且处理成本比企业之前采用的铁炭微电解+A2O工艺降低约70%。铁铜双金属材料在制革行业废水处理中的应用尚在探索中，期待未来可工程应用。