State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, Yunnan, 650093, PR China; Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650093, PR China.
State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, Yunnan, 650093, PR China; Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650093, PR China.
Environ Pollut. 2019 Jan;244:938-946. doi: 10.1016/j.envpol.2018.08.054. Epub 2018 Sep 5.
A novel trithiocyanuric acid-modified corn bract (TCA-CCB) was prepared, and its removal properties for Hg were investigated. TCA-CCB showed a remarkable absorbability for Hg in mixed ion solutions. Adsorption kinetics experiments indicated that the removal of Hg on TCA-CCB was quick, with a removal rate of 99.07% within 5 min. In addition, the removal rate of Hg exceeded 98% over all pH conditions. The adsorption process can be best described by pseudo-second-order kinetic and Hill isotherm models. The saturated adsorption capacity of TCA-CCB for Hg was 390 mg/g. The TCA-CCB could efficiently adsorb Hg from the simulated wastewater and reduce the Hg concentration from 10 ppm to 12.35 ppb, which was lower than the greatest allowable value of 50 ppb and satisfied the emission standards required by the Chinese government. Moreover, the removal rate of Hg was beyond 99% after three cycles. The results of the zeta potential and X-ray photoelectron spectroscopy (XPS) implied that the chelation and ion exchange between amino/thiol groups and Hg played a significant role in the improvement of the adsorption properties. The corn bract modified by trithiocyanuric acid exhibits apparent advantages in the removal of Hg from ppm to ppb due to its high selectivity, adsorption capacity and stability.
一种新型三硫氰基均三嗪修饰的玉米苞叶（TCA-CCB）被制备，并研究了其对汞的去除性能。TCA-CCB 在混合离子溶液中对汞表现出显著的吸附能力。吸附动力学实验表明，TCA-CCB 对汞的去除速度很快，在 5 分钟内去除率达到 99.07%。此外，汞的去除率在所有 pH 值条件下均超过 98%。吸附过程可以用拟二级动力学和 Hill 等温线模型很好地描述。TCA-CCB 对汞的饱和吸附容量为 390mg/g。TCA-CCB 可以从模拟废水中有效地吸附汞，将汞浓度从 10ppm 降低至 12.35ppb，低于中国政府规定的最大允许值 50ppb，并满足政府的排放要求。此外，经过三次循环后，汞的去除率仍超过 99%。Zeta 电位和 X 射线光电子能谱（XPS）的结果表明，氨基/巯基与汞之间的螯合和离子交换在提高吸附性能方面起着重要作用。由于其高选择性、吸附容量和稳定性，三硫氰基均三嗪修饰的玉米苞叶在从 ppm 到 ppb 去除汞方面表现出明显的优势。
