Ngambia Audrey, Ifthikar Jerosha, Shahib Irshad Ibran, Jawad Ali, Shahzad Ajmal, Zhao Mengmeng, Wang Jia, Chen Zhulei, Chen Zhuqi
Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, PR China.
Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, PR China; Department of Environmental Engineering, School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, PR China.
Sci Total Environ. 2019 Nov 15;691:306-321. doi: 10.1016/j.scitotenv.2019.07.003. Epub 2019 Jul 3.
A rod-like SDBC-Mg(II) composite was synthesized and optimized in the conditions of 25% Mg(II) loading and 500 °C calcination temperature. As-prepared SDBC-25%Mg(II)-500 adsorbent attained equilibrium in 30 min, with an extraordinary capacity of 2931.76 mg g (Pb(II)) and 861.11 mg g (Cd(II)), revealing a promising adsorbent for the removal of such metals so far. The adsorption kinetics was well described by the pseudo-second-order model while the adsorption isotherm could be fitted by Redlich-Peterson model. Furthermore, SDBC-25%Mg(II)-500 has a high anti-interference and selectivity in the presence of competing ions/other environmental factors and, also effectively eliminates >99% of Pb, Cd, Ag and Cu ions from pond water, lake water and tap water. The adsorption process demonstrated a synergetic adsorption mechanism comprised of ion exchange with Mg(II), coordination with surface and inner carboxylic or carbonyl functional groups and co-precipitations as metal silicates, which is responsible for its superb adsorption performance. Besides, surface carvings of Mg(II) and tunnels on the rods resulting from the sludge carbonization provided a high surface area (91.57 m g), extra sorption sites and room for easy pollutant diffusion which contributed to surface physical adsorption. Furthermore, this technique demonstrate an alternative pathway that will relieve the burdens of sewage sludge treatment process and turn this solid waste into highly efficient adsorbent for eliminating heavy metal ions from wastewater. This can be considered as a feasible waste resource utilization to meet with the requirement from both ecology and economy for auspicious applications in industries.
合成了一种棒状的SDBC-Mg(II)复合材料，并在Mg(II)负载量为25%、煅烧温度为500℃的条件下进行了优化。制备的SDBC-25%Mg(II)-500吸附剂在30分钟内达到平衡，对Pb(II)的吸附容量高达2931.76 mg g，对Cd(II)的吸附容量为861.11 mg g，是目前去除此类金属的一种很有前景的吸附剂。吸附动力学可用准二级模型很好地描述，吸附等温线可用Redlich-Peterson模型拟合。此外，SDBC-25%Mg(II)-500在存在竞争离子/其他环境因素时具有高抗干扰性和选择性，并且能有效去除池塘水、湖水和自来水中>99%的Pb、Cd、Ag和Cu离子。吸附过程表现出一种协同吸附机制，包括与Mg(II)的离子交换、与表面和内部羧基或羰基官能团的配位以及作为金属硅酸盐的共沉淀，这是其优异吸附性能的原因。此外，污泥碳化导致的棒状结构上Mg(II)的表面刻蚀和隧道提供了高比表面积(91.57 m g)、额外的吸附位点和便于污染物扩散的空间，有助于表面物理吸附。此外，该技术展示了一条替代途径，将减轻污水污泥处理过程的负担，并将这种固体废物转化为用于去除废水中重金属离子的高效吸附剂。这可被视为一种可行的废物资源利用方式，以满足生态和经济方面的要求，在工业中得到良好应用。
