Department of Environmental Science & Engineering, Marwadi University, Rajkot, 360 003, Gujarat, India; Hyderabad Zonal Centre, CSIR-National Environmental Engineering Research Institute, IICT Campus, Tarnaka, Hyderabad, 500 007, Telangana, India.
Analytical and Environmental Science Division & Centralized Instrument Facility, CSIR-Central Salt & Marine Chemicals Research Institute, Bhavnagar, 364 002, Gujarat, India.
Chemosphere. 2022 Jul;298:134360. doi: 10.1016/j.chemosphere.2022.134360. Epub 2022 Mar 19.
Polyaniline supported titanium dioxide nanoparticles (PTs) were fabricated using chemical oxidative aniline polymerization in the presence of titanium dioxide with ammonium peroxydisulfate as an oxidant. The synthesized PTs were thoroughly characterized for their morphological and functional features. PTs were employed for the photodegradation of acidic herbicides; 2,4-dichlorophenoxyacetic acid (2,4-D) and triclopyr acid (TCP). PT's surface modifications were imparted and their herbicide removal efficiencies were compared. The best operating conditions for adsorption/photocatalysis were 0.5 g/L photocatalyst, 10 mg/L concentration of individual herbicides resulted in 90.72% removal of TCP at pH 4 and 99.91% removal of 2,4-D at pH 5. Adsorption kinetics of herbicides, onto PT-1 showed the equilibrium attainment within 30 min and experimental data obeyed pseudo-second order model for TCP and 2,4-D removal which was governed by chemisorption. Analysis of TCP and 2,4-D adsorption indicated that the removal followed Sips model for TCP removal while Redlich-Peterson model explained the removal of 2,4-D by PT-1. Rate constants indicated that the amount of TiO in the PTs played an important role in removing the herbicides and PT-1 material excellent remarkable activity for three cycles of photodegradation. Thus, this work reports the polymerization of aniline onto TiO and their utility as photocatalyst for the expulsion of 2,4-D and TCP from water.
采用化学氧化苯胺聚合法，在过硫酸铵存在下，将钛白粉作为氧化剂，制备了聚苯胺负载的二氧化钛纳米粒子（PTs）。对合成的 PTs 进行了形态和功能特征的全面表征。PTs 被用于光降解酸性除草剂；2,4-二氯苯氧乙酸（2,4-D）和三氯吡酸（TCP）。对 PT 的表面进行了改性，并比较了它们的除草剂去除效率。吸附/光催化的最佳操作条件为 0.5 g/L 光催化剂，单独除草剂的浓度为 10 mg/L，在 pH 值为 4 时 TCP 的去除率为 90.72%，在 pH 值为 5 时 2,4-D 的去除率为 99.91%。PT-1 对除草剂的吸附动力学表明，在 30 分钟内达到平衡，TCP 和 2,4-D 的去除实验数据符合准二级动力学模型，这是由化学吸附控制的。TCP 和 2,4-D 吸附分析表明，TCP 的去除遵循 Sips 模型，而 2,4-D 的去除则由 Redlich-Peterson 模型解释。速率常数表明，PTs 中 TiO 的含量在去除除草剂方面起着重要作用，PT-1 材料对 2,4-D 和 TCP 的光降解具有优异的循环三次的活性。因此，本工作报道了苯胺在 TiO 上的聚合及其作为光催化剂在水中去除 2,4-D 和 TCP 的应用。
