Zhu Hu, Li Lu, Chen Wendan, Tong Yuejin, Wang Xuesong
Engineering Research Center of Industrial Biocatalysis, Fujian Province University, Fujian Provincial Key Laboratory of Polymer Materials, College of Chemistry and Materials Science, Fujian Normal University, 32 Shangsan Road, Fuzhou 350007, People's Republic of China.
Engineering Research Center of Industrial Biocatalysis, Fujian Province University, Fujian Provincial Key Laboratory of Polymer Materials, College of Chemistry and Materials Science, Fujian Normal University, 32 Shangsan Road, Fuzhou 350007, People's Republic of China.
J Hazard Mater. 2021 Aug 15;416:125922. doi: 10.1016/j.jhazmat.2021.125922. Epub 2021 Apr 19.
A coral-like hierarchical porous magnesium hydroxide (HPMH) with various surface area and pore volume was controllably prepared using a simple one-step hydrothermal process, for which MgO, water and citric acid were applied. The citric acid (CA), as a structure-directing molecule, is a key factor in regulating the pore structure of HPMH products. With different additive dosages, the nanostructure, surface area and pore volume of HPMH products can be controllably regulated. The MH-CA20 product (prepared in the presence of 20 wt% CA) with high BET surface area (159 m/g) and pore volume (0.75 cm/g) was used to investigate the adsorption properties for Pb(II) and Cd(II) ions. The experimental adsorption capabilities of the MH-CA20 for Pb(II) and Cd(II) are respectively 4535 and 3530 mgg, very close to the maximum adsorption capabilities calculated by Langmuir equation (4545 and 3571 mgg). According to the adsorption kinetics and adsorption isotherm data, the adsorption process conforms to the Pseudo-second-order and Langmuir model, indicating that heavy metal ions conduct monolayer chemical adsorption mechanism. Since the preparation of HPMH is simple, low-cost and filtrate recycling, the process can easily be scaled up and could be a good candidate for application in tackling different wastewater.
采用简单的一步水热法，以氧化镁、水和柠檬酸为原料，可控地制备了具有不同表面积和孔体积的珊瑚状分级多孔氢氧化镁（HPMH）。柠檬酸（CA）作为结构导向分子，是调节HPMH产物孔结构的关键因素。通过不同的添加剂用量，可以可控地调节HPMH产物的纳米结构、表面积和孔体积。采用具有高BET表面积（159 m²/g）和孔体积（0.75 cm³/g）的MH-CA20产物（在20 wt% CA存在下制备）研究其对Pb(II)和Cd(II)离子的吸附性能。MH-CA20对Pb(II)和Cd(II)的实验吸附容量分别为4535和3530 mg/g，非常接近朗缪尔方程计算的最大吸附容量（4545和3571 mg/g）。根据吸附动力学和吸附等温线数据，吸附过程符合准二级动力学和朗缪尔模型，表明重金属离子进行单层化学吸附机制。由于HPMH的制备简单、成本低且滤液可循环利用，该工艺可轻松放大，有望成为处理不同废水的良好候选工艺。
