Azam Mohammad, Wabaidur Saikh Mohammad, Khan Mohammad Rizwan, Al-Resayes Saud I, Islam Mohammad Shahidul
Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
Polymers (Basel). 2022 Feb 25;14(5):914. doi: 10.3390/polym14050914.
In the current study we prepared cost-effective adsorbents based on ajwa date pits to remove Cu(II) ions from aqueous medium. Adsorbents were studied using scanning electron microscopy (SEM), FT-IR, and Brunauer-Emmett-Teller (BET) methods to characterize the surface functionalities, morphology, pore size, and particle size. The concentration of Cu(II) ions in the studied samples was determined by atomic adsorption spectrometry technique (AAS). Adsorption method was performed sequentially in a batch system followed by optimization by studying the numerous conditions, for instance the initial amounts of Cu(II) ions, dosages of the adsorbent, contact time, and pH of the solution. The ideal pH observed for maximum adsorption capacity was ~6.5. Langmuir and Freundlich isotherm models correctly predicted the investigation results, with the maximum monolayer adsorption capacities for Cu(II) ions at 328 K being 1428.57 mg/g (treated ajwa date pits, TADP) and 1111.1 mg/g for as produced ajwa date pits (ADP). It was revealed that TADP possess greater adsorption capability than ADP. Recovery investigations revealed that the saturated adsorbents eluted the maximum metal with 0.1 M HCl. Cu(II) ions adsorption was observed to be reduced by 80-89% after the second regeneration cycle. For the raw and chemically processed ajwa date pits adsorbent, the Langmuir model performed significantly better than the Freundlich model. The results demonstrated that the adsorbent made from ajwa date pits could be an economical and environmentally friendly alternative for removing Cu(II) ion pollutant from aqueous media.
在当前研究中，我们制备了基于阿吉瓦枣核的经济高效吸附剂，用于从水介质中去除铜离子（Cu(II)）。采用扫描电子显微镜（SEM）、傅里叶变换红外光谱（FT-IR）和布鲁诺尔-埃米特-泰勒（BET）方法对吸附剂进行研究，以表征其表面官能团、形态、孔径和粒径。通过原子吸收光谱技术（AAS）测定研究样品中铜离子的浓度。吸附实验在间歇系统中依次进行，然后通过研究多种条件进行优化，例如铜离子的初始量、吸附剂用量、接触时间和溶液的pH值。观察到最大吸附容量的理想pH值约为6.5。朗缪尔和弗伦德利希等温线模型正确地预测了研究结果，在328 K时，处理后的阿吉瓦枣核（TADP）对铜离子的最大单层吸附容量为1428.57 mg/g，未处理的阿吉瓦枣核（ADP）为1111.1 mg/g。结果表明，TADP比ADP具有更强的吸附能力。回收研究表明，饱和吸附剂用0.1 M盐酸洗脱了最大量的金属。在第二个再生循环后，观察到铜离子的吸附减少了80 - 89%。对于未处理和化学处理的阿吉瓦枣核吸附剂，朗缪尔模型的表现明显优于弗伦德利希模型。结果表明，由阿吉瓦枣核制成的吸附剂可能是一种经济且环保的替代方案，用于从水介质中去除铜离子污染物。
