ABSTRACT

The study evaluated the effectiveness of an aquatic plant, Canna indica to remove 2,4,6-Trichlorophenol (TCP) from aqueous solution in a hydroponic set-up. The effects of TCP initial concentration (50–250 mg/L) and solution pH (4–9) on TCP biosorption were investigated. The removal efficiency increased with days and initial concentrations. The optimum removal was obtained at pH 4.0. The equilibrium data obtained were analysed by Langmuir, Freundlich, Temkin, Elovich and Dubinin-Radushkevich isotherm models. The equilibrium time was found to be 20 days. The Langmuir and Freundlich model gave the best correlation with the experimental data. According to Langmuir model, the maximum monolayer biosorption capacity of C. indica for TCP was found to be 52.08 mg/g, at 25 ± 2°C. The adsorption was found to follow the pseudo-first-order kinetics. The intraparticle diffusion model revealed that intraparticle diffusion is not the sole rate-limiting step for the biosorption process. Thermodynamic parameter such as standard free energy (ΔG _o) was −2537.697 kJ/mol. This showed that the biosorption process was highly spontaneous and proceeded mainly by chemisorption process. C. indica used in this study is eco-friendly, widely available and offers greater potential for wastewater treatment for removal of chlorinated pollutants such as TCP from aqueous solutions.

摘要

该研究评估了水培条件下水生植物印度anna（Canna indica）从水溶液中去除2,4,6-三氯苯酚（TCP）的有效性。研究了TCP初始浓度（50–250 mg / L）和溶液pH（4–9）对TCP生物吸附的影响。去除效率随着天数和初始浓度的增加而增加。在pH 4.0时可获得最佳去除效果。通过Langmuir，Freundlich，Temkin，Elovich和Dubinin-Radushkevich等温线模型分析获得的平衡数据。发现平衡时间为20天。Langmuir和Freundlich模型与实验数据具有最佳的相关性。根据Langmuir模型，印度C草的最大单层生物吸附能力在25±2°C下，TCP的最大残留量为52.08 mg / g。发现吸附遵循拟一级动力学。颗粒内扩散模型表明，颗粒内扩散不是生物吸附过程的唯一限速步骤。标准自由能（ΔG _o）等热力学参数为-2537.697 kJ / mol。这表明生物吸附过程是高度自发的，并且主要通过化学吸附过程进行。这项研究中使用的印度。茶是生态友好的，可广泛获得，并为废水处理中从水溶液中去除氯化污染物（如TCP）提供了更大的潜力。