Abstract

Cadmium is one of the toxic heavy metal that is discharged into the surroundings by various routes such as sedimentary rocks, weathering and erosion of rock, earth’s crust, marine phosphate and phosphorites, forest fires etc. However battery manufacturing industry, plated containers, mining, auto exhaust, smelting of nonferrous metals, cigarettes ore dressing, and galvanized pipes are the main anthropogenic sources of cadmium heavy metal in environment. Ingestion of cadmium in human body increases the risk of many diseases. Many techniques have been applied for the removal of cadmium heavy metal ions from water. The aim of the current work is to propose economical material for effective cadmium ion removal from aqueous phase. A Pavo cristatus feather which is locally available and low-cost is used as an adsorbent for the removal of cadmium ions from water. The adsorption ability of Pavo cristatus feather has been investigated as a function of concentration of cadmium, pH of solution, adsorbate concentration, contact time and temperature. Maximum adsorption of cadmium on Pavo cristatus feather was observed at 5 pH of the solution. Adsorption of cadmium on Pavo cristatus feather was initially found to increase with increase in concentration of cadmium, time of contact and adsorbate concentration. The Langmuir, Freundlich and Temkin adsorption isotherm models were applied to analyse the experimental data. The experimental data was well fitted to Langmuir isotherm model. However, the maximum Langmuir adsorption capacity for cadmium on Pavo cristatus feather at pH 5 was 64.52 mg/g. The kinetics study was examined using the pseudo first order and pseudo second order kinetic models and was best described by the pseudo second order model. Thermodynamic parameters such as the change of Gibbs free energy, entropy and enthalpy of adsorption were also calculated. The study showed that Pavo cristatus feather can be used as a low cost and efficient adsorbent for removal of heavy metal ions from industrial wastewater/water. This material may also be utilized for removal of other toxic heavy mental ions from water.

中文翻译：

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使用Pavo Cristatus（孔雀）羽毛粉作为吸附剂从水溶液中去除镉离子

摘要

镉是有毒的重金属之一，它通过各种途径排入周围环境，例如沉积岩，岩石的风化和侵蚀，地壳，海洋磷酸盐和亚磷酸盐，森林火灾等。但是，电池制造业，电镀容器，采矿，汽车尾气，有色金属冶炼，香烟矿石选矿和镀锌管是环境中镉重金属的主要人为来源。人体摄入镉会增加许多疾病的风险。已应用许多技术从水中去除镉重金属离子。当前工作的目的是提出一种经济有效地从水相中去除镉离子的材料。一个蓝孔雀本地可用的低成本羽毛被用作吸附剂，用于从水中去除镉离子。已经研究了Pavo cristatus羽毛的吸附能力与镉浓度，溶液的pH值，吸附物浓度，接触时间和温度的关系。在溶液的5 pH下观察到镉在Pavo cristatus羽毛上的最大吸附。Pavo cristatus对镉的吸附最初发现羽毛随着镉浓度，接触时间和被吸附物浓度的增加而增加。用Langmuir，Freundlich和Temkin吸附等温线模型分析实验数据。实验数据非常适合Langmuir等温线模型。但是，在pH 5时，Langmuir对Pavo cristatus羽毛的镉最大吸附容量为64.52 mg / g。使用伪一级和伪二级动力学模型检查了动力学研究，并用伪二级模型最好地描述了动力学研究。还计算了吉布斯自由能的变化，熵和吸附焓等热力学参数。研究表明，Pa猴羽毛可用作从工业废水/水中去除重金属离子的低成本高效吸附剂。该材料还可用于从水中去除其他有毒的重金属离子。