Laboratory of Green Chemistry, School of Engineering Science, Lappeenranta University of Technology, Sammonkatu 12, FI 50130, Mikkeli, Finland.
Laboratory of Green Chemistry, School of Engineering Science, Lappeenranta University of Technology, Sammonkatu 12, FI 50130, Mikkeli, Finland.
J Environ Sci (China). 2017 Jan;51:97-110. doi: 10.1016/j.jes.2016.08.011. Epub 2016 Sep 27.
Synthesis of malachite@clay nanocomposite was successfully carried out for the removal of cationic (Methylene Blue, MB) and anionic dyes (Congo Red, CR) from synthetic wastewater. Nanocomposite was characterized by TEM, SEM, FT-IR, EDS analysis and zeta potential. TEM analysis indicated that the particle diameter of nanocomposite was in the range of 14 to 23nm. Various important parameters viz. contact time, concentration of dyes, nanocomposite dosage, temperature and solution pH were optimized to achieve maximum adsorption capacity. In the case of MB, removal decreased from 99.82% to 93.67% while for CR, removal decreased from 88.55% to 75.69% on increasing dye concentration from 100 to 450mg/L. pH study confirmed the higher removal of CR in acidic range while MB removal was higher in alkaline range. Kinetic study revealed the applicability of pseudo-second-order model for the adsorption of both dyes. Negative values of ΔG for both systems suggested the feasibility of dye removal and support for spontaneous adsorption of CR and MB on nanocomposite. Nanocomposite showed 277.77 and 238.09mg/g Langmuir adsorption capacity for MB and CR respectively. Desorption of dyes from the dye loaded nanocomposite was easily carried out with acetone. The results indicate that the prepared malachite@clay nanocomposite is an efficient adsorbent with high adsorption capacity for the aforementioned dyes.
成功制备了孔雀石@粘土纳米复合材料，用于从合成废水中去除阳离子（亚甲基蓝，MB）和阴离子染料（刚果红，CR）。通过 TEM、SEM、FT-IR、EDS 分析和 ζ 电位对纳米复合材料进行了表征。TEM 分析表明，纳米复合材料的粒径范围为 14 至 23nm。优化了各种重要参数，如接触时间、染料浓度、纳米复合材料用量、温度和溶液 pH 值，以达到最大吸附容量。对于 MB，去除率从 99.82%降至 93.67%，而对于 CR，当染料浓度从 100 增至 450mg/L 时，去除率从 88.55%降至 75.69%。pH 值研究证实，CR 在酸性范围内的去除率较高，而 MB 在碱性范围内的去除率较高。动力学研究表明，准二级模型适用于两种染料的吸附。对于这两个系统，ΔG 的负值表明染料去除的可行性，并支持 CR 和 MB 在纳米复合材料上的自发吸附。纳米复合材料对 MB 和 CR 的 Langmuir 吸附容量分别为 277.77 和 238.09mg/g。用丙酮很容易将负载染料的纳米复合材料上的染料解吸。结果表明，所制备的孔雀石@粘土纳米复合材料是一种高效的吸附剂，对上述染料具有高吸附容量。
