In this study, unmodified biosorbent was obtained from Arachis hypogea husk and applied to remove hexavalent chromium [Cr(VI)] from aqueous media through batch technique. The independent variables (contact time, pH of the solution and initial Cr(VI) concentration) influencing the adsorption process were optimized by central composite design (CCD) found in response surface methodology of the Design-Expert software 12.0.0 at a fixed temperature of 30 ± 0.5 °C. Furthermore, equilibrium sorption isotherms and kinetics studies were also investigated. The ANOVA component of the CCD indicated that all the process independent variables investigated had significant impacts on the sorption capacity of Cr(VI) by Arachis hypogea husk. The obtained experimental data showed that at the optimized 120 min contact time, 8.0 pH of the aqueous solution and 50 mg/L initial Cr(VI) concentration resulted in an optimum adsorption capacity of 2.355 mg/g. Equilibrium sorption isotherm and kinetic studies showed that Redlich–Peterson adsorption isotherm and pseudo-second-order kinetic models fitted well to the equilibrium data. The unmodified adsorbent from Arachis hypogea husk was found to be efficient for Cr(VI) decontamination from the aqueous media.

中文翻译：

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使用响应表面方法（RSM）的中央复合设计（CCD）对水介质中六价铬的生物吸附进行优化

在这项研究中，未经修饰的生物吸附剂是从Arachis hypogea皮中获得的，并用于通过分批技术从水性介质中去除六​​价铬[Cr（VI）]。通过在固定温度下使用Design-Expert软件12.0.0的响应面方法找到的中央复合设计（CCD），优化了影响吸附过程的独立变量（接触时间，溶液的pH值和初始Cr（VI）浓度）。 30±0.5°C。此外，还研究了平衡吸附等温线和动力学研究。CCD的ANOVA成分表明，所研究的所有与工艺无关的变量均对Arachis hypogea对Cr（VI）的吸附能力有重大影响。皮 获得的实验数据表明，在最佳的120分钟接触时间，8.0 pH的水溶液和50 mg / L的初始Cr（VI）浓度下，最佳吸附容量为2.355 mg / g。平衡吸附等温线和动力学研究表明，Redlich-Peterson吸附等温线和拟二阶动力学模型非常适合平衡数据。发现来自花生壳的未改性吸附剂对于从水性介质中去除六​​价铬是有效的。