The aim of this study was to model and optimize the adsorption of Pb(II) ions from an aqueous solution using Africa elemi seed, mucuna shell and oyster shell modified with orthophosphorous acid used as adsorbents. The influence of operational parameters such as adsorbent dosage, initial pH and contact time was evaluated by response surface methodology (RSM). The interactions between the operational parameters were evaluated using Box–Behnken design of response surface methodology. The optimum conditions for maximum removal of Pb(II) ions were observed at pH of 2.0, 100 mg adsorbent dosage and 70 min of contact time, with correlation coefficient R², 0.996 for Africa elemi seed adsorbent; pH of 6.0, 100 mg adsorbent dosage and 40 min contact time with R² 0.996 for mucuna shell adsorbent; and pH of 6.0, 100 mg adsorbent dosage and contact time of 40 min for oyster shell adsorbent. The ANOVA results obtained from the RSM were analyzed using second-order polynomial equations, and the contour plots showed the interaction among the variables of the adsorption. This shows that the prepared low-cost adsorbents can be effectively adopted for the removal of Pb(II) ions from industrial wastewaters.

中文翻译：

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使用非洲细粒种子，粘液壳和牡蛎壳作为吸附剂从水溶液中吸附铅（II），并使用Box–Behnken设计进行优化

这项研究的目的是模拟和优化使用正磷酸修饰的非洲象鼻种子，粘液壳和牡蛎壳从水溶液中吸附Pb（II）离子的吸附剂。通过响应表面方法（RSM）评估了操作参数（如吸附剂剂量，初始pH值和接触时间）的影响。使用响应面方法的Box–Behnken设计评估了运行参数之间的相互作用。在pH为2.0，吸附剂剂量为100 mg，接触时间为70 min的条件下，观察到了最大程度去除Pb（II）离子的最佳条件，非洲elemi种子吸附剂的相关系数R ²为0.996。pH值为6.0，吸附剂剂量为100 mg，与R ²接触时间为40分钟黏液壳吸附剂为0.996; pH值为6.0，牡蛎壳吸附剂的吸附剂量为100 mg，接触时间为40分钟。使用二阶多项式方程分析从RSM获得的ANOVA结果，等高线图显示了吸附变量之间的相互作用。这表明所制备的低成本吸附剂可有效地用于去除工业废水中的Pb（II）离子。