Kim Kyungmin, Kim Dujin, Kim Taeyeon, Kim Bong-Geun, Ko Donghyun, Lee Junsoo, Han Yujin, Jung Ji Chul, Na Hyon Bin
Department of Chemical Engineering, Myongji University Yongin Gyeonggi-do 17058 Republic of Korea
RSC Adv. 2019 May 16;9(27):15257-15264. doi: 10.1039/c9ra00895k. eCollection 2019 May 14.
Phosphate is a ubiquitous pollutant in aquatic systems, and increasingly stringent post-treatment phosphate effluent standards necessitate increasingly efficient removal techniques. In this study, mesoporous lanthanum hydroxide (MLHO) was synthesized by a hard-template method using ordered mesoporous silica, and its potential as an adsorbent for high-efficiency phosphate removal in aqueous solutions was tested. The porosity characteristics of MLHOs were controlled by adjusting the template structure and synthesis conditions. MLHO adsorbents showed great potential for phosphate removal from solutions containing both high and low initial phosphate concentrations. The phosphate adsorption capacity of MLHO strongly depended on its surface area as this process was governed by monolayer adsorption. Moreover, the phosphate removal performance of MLHO was affected by its structural properties. MLHO showed a high adsorption capacity of 109.41 mg P g at 28 °C ( by the Langmuir isotherm model). Further, it showed ultrafast adsorption in a solution with low initial concentration of 2 mg P/L; within the first 10 min, 99.8% of phosphate was removed, and the phosphorus concentration remaining in the solution dramatically reduced to 4 μg P/L. These findings suggest that MLHO adsorbent is a good candidate for rapid and efficient low-concentration phosphate removal to meet the increasingly stringent discharge standards for wastewater treatment plants.
磷酸盐是水生系统中普遍存在的污染物，越来越严格的磷酸盐废水处理后排放标准要求采用越来越高效的去除技术。在本研究中，使用有序介孔二氧化硅通过硬模板法合成了介孔氢氧化镧（MLHO），并测试了其作为水溶液中高效去除磷酸盐吸附剂的潜力。通过调整模板结构和合成条件来控制MLHO的孔隙率特征。MLHO吸附剂对于从初始磷酸盐浓度高和低的溶液中去除磷酸盐均显示出巨大潜力。MLHO的磷酸盐吸附容量强烈依赖于其表面积，因为该过程受单层吸附控制。此外，MLHO的磷酸盐去除性能受其结构性质影响。在28°C时，MLHO表现出109.41 mg P/g的高吸附容量（根据朗缪尔等温线模型）。此外，在初始浓度为2mg P/L的低浓度溶液中，它表现出超快吸附；在最初10分钟内，99.8%的磷酸盐被去除，溶液中剩余的磷浓度急剧降至4μg P/L。这些发现表明，MLHO吸附剂是快速高效去除低浓度磷酸盐的良好候选材料，可满足污水处理厂日益严格的排放标准。
