The present study aimed to remove the heavy metal compounds present in wastewater. In this study, we used hexavalent chromium Cr (VI) as a heavy metal compound, and coconut shell was used as a promising green bio-sorbent to remove Cr (VI) from wastewater. Coconut shells are readily available and are termed as waste materials. Various parameters such as contact time, pH of the solution, initial Cr (VI) concentration, and amount of coconut shell were studied. The adsorption data were fitted with various isotherm models. The Langmuir and Freundlich isotherm models were the best fit for the experimental data, and the maximum adsorption capacity was found to be 16.39 and 12.19 mg/g, respectively. Kinetic and thermodynamic studies were performed to assess the feasibility of the process. The pseudo-second-order kinetic model is also signified that the Cr (VI) adsorbent capacity was due to particle diffusion. To identify the morphological properties of the adsorbent various analysis such as Scanning Electron microscope (SEM) and BET surface area were performed. The experimental results and rate of adsorption, and the adsorption process was found to be feasible and endothermic in nature.

中文翻译：

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以椰壳为绿色吸附剂从水溶液中吸附降解六价铬

本研究旨在去除废水中存在的重金属化合物。在这项研究中，我们使用六价铬 Cr (VI) 作为重金属化合物，椰子壳作为一种有前途的绿色生物吸附剂来去除废水中的 Cr (VI)。椰子壳很容易获得，被称为废料。研究了各种参数，例如接触时间、溶液的 pH 值、初始 Cr (VI) 浓度和椰子壳的量。吸附数据符合各种等温线模型。Langmuir 和 Freundlich 等温线模型最适合实验数据，发现最大吸附容量分别为 16.39 和 12.19 mg/g。进行动力学和热力学研究以评估该过程的可行性。准二级动力学模型也表明 Cr (VI) 吸附容量是由于粒子扩散。为了鉴定吸附剂的形态特性，进行了各种分析，例如扫描电子显微镜 (SEM) 和 BET 表面积。实验结果和吸附速率，以及吸附过程在性质上是可行的和吸热的。