Sarojini G, Venkatesh Babu S, Rajamohan N, Rajasimman M
Department of Petrochemical Engineering, SVS College of Engineering, Coimbatore, India.
Department of Petroleum Engineering, JCT College of Engineering & Technology, Coimbatore, India.
Environ Res. 2022 Mar;204(Pt B):112132. doi: 10.1016/j.envres.2021.112132. Epub 2021 Sep 25.
In this experimental investigation, feasibility and performance of a polymer hybrid bio-nano composite were evaluated to remove malachite green (MG) under controlled environment conditions. The polymer hybrid bio-nanocomposite was characterized using FTIR, SEM and EDS. The influence of operating variables, namely effect of pH (2-11), nanocomposite dosage (20-100 mg), initial MG concentration (10- 200 mg/L), contact time (10-120 min) and temperature (298-318 K) were explored. The maximum removal efficiency (RE) of 99.79% was achieved at neutral pH at the dosage level of 50 mg with the initial MG concentration of 150 mg/L in 40 min. The equilibrium results revealed that the adsorption of MG data fitted to Langmuir isotherm (R > 0.970) indicating monolayer adsorption. The maximum adsorption capacity of polymer hybrid nanocomposite was found to be 384.615 mg/g. Kinetic studies were performed using five kinetic models and results showed the pseudo second order model fitted very well with the MG adsorption data (R > 0.990). The thermodynamic results confirmed that MG adsorption onto polymer hybrid nanocomposite is feasible and (ΔS = 0.2893 kJ/mol K), spontaneous (ΔH = 81.103 kJ/mol K) and exothermic (ΔG < 0). A mechanism is also proposed for the removal of MG using the polymer nanocomposite and identified that electrostatic attraction and hydrogen bonding as the major mechanism for removal of MG. FTIR results confirmed the presence of carboxyl (-COO) and hydroxyl (-OH) groups which helped in effective binding of cationic dye. The overall results revealed that polymer nanocomposite could be used as a potential adsorbent for removing MG from aqueous solution.
在本实验研究中，评估了一种聚合物杂化生物纳米复合材料在可控环境条件下去除孔雀石绿（MG）的可行性和性能。使用傅里叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）和能谱仪（EDS）对该聚合物杂化生物纳米复合材料进行了表征。探讨了操作变量的影响，即pH值（2 - 11）、纳米复合材料用量（20 - 100毫克）、初始MG浓度（10 - 200毫克/升）、接触时间（10 - 120分钟）和温度（298 - 318 K）的影响。在中性pH值、用量为50毫克、初始MG浓度为150毫克/升的条件下，40分钟内实现了99.79%的最大去除效率（RE）。平衡结果表明，MG的吸附数据符合朗缪尔等温线（R > 0.970），表明为单层吸附。发现聚合物杂化纳米复合材料的最大吸附容量为384.615毫克/克。使用五种动力学模型进行了动力学研究，结果表明准二级模型与MG吸附数据拟合得非常好（R > 0.990）。热力学结果证实，MG吸附到聚合物杂化纳米复合材料上是可行的（ΔS = 0.2893千焦/摩尔·K）、自发的（ΔH = 81.103千焦/摩尔·K）且放热的（ΔG < 0）。还提出了使用聚合物纳米复合材料去除MG的机制，并确定静电吸引和氢键是去除MG的主要机制。FTIR结果证实了羧基（-COO）和羟基（-OH）基团的存在，这有助于阳离子染料的有效结合。总体结果表明，聚合物纳米复合材料可作为从水溶液中去除MG的潜在吸附剂。
