AlSalem Huda S, Alatawi Raedah A S, Bukhari Abeer Abdulaziz H, Alnawmasi Jawza Sh, Zghab Imen, El-Desouky Mohamed G, Almabadi Meshal H, Alnakhli Zainab Hassan, Elsayed Nadia H
Department of Chemistry, College of Science, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia.
Department of Chemistry, Faculty of Science, University of Tabuk, Tabuk 71421, Saudi Arabia.
Int J Biol Macromol. 2024 Dec;283(Pt 1):137517. doi: 10.1016/j.ijbiomac.2024.137517. Epub 2024 Nov 13.
The study aimed to enhance the stability and efficiency of removing bivalent Pb(II) by encapsulating AlNi-layered double hydroxide (LDH) in chitosan and itaconic acid to create an adsorbent with chemically active sites. The resulting material, AlNi-LDH/CS, underwent thorough property analysis using XRD, FT-IR, XPS, EDX, N adsorption/desorption isotherm, and FESEM to find out what textural characteristics it has. Specifically, nitrogen adsorption/desorption isotherms were utilized to assess the textural properties of AlNi-LDH/CS. The Al/Ni-LDH/CS surface displayed a specific surface area of 71.95 m/g and an average pore size of 2.537 nm, consistent with the platelets' external surface. The effects of dose, pH, temperature, and starting concentration on the adsorption process were also investigated in this study. The adsorption characteristics have been examined by means of equilibrium and adsorption kinetics. The adsorption process adhered to the pseudo-second-order and Langmuir isotherm models. The predominant adsorption process was found to be chemisorption, which had an adsorption energy of 28.42 kJ·mol. An endothermic and spontaneous adsorption process is suggested by the increase in metal absorption at increasing temperatures. The Box-Behnken design software was utilized to establish the optimal adsorption parameters as pH 5, a dosage of 0.2 g of AlNi-LDH/CS per 25 mL, and an adsorption capacity of 453.05 mg/g for the Pb(II) arsenate solution. For the composite sponge to be most effective in adsorbing arsenate and be used in water purification procedures, these factors are essential. The adsorption process was successfully improved with few planned tests by applying the Box-Behnken design and response surface technique aspects of the Design-Expert software. An evaluation of the adsorbent's reusability using six successive cycles of adsorption and desorption confirmed its stability and showed no discernible decrease in removal efficiency. Additionally, it retained its original chemical composition before and after reuse, showcased consistent efficiency, and maintained uniform XRD data.
该研究旨在通过将铝镍层状双氢氧化物（LDH）包裹在壳聚糖和衣康酸中来提高去除二价铅（II）的稳定性和效率，从而制备出具有化学活性位点的吸附剂。对所得材料AlNi-LDH/CS进行了全面的性能分析，采用XRD、FT-IR、XPS、EDX、N吸附/解吸等温线和FESEM来确定其具有何种结构特征。具体而言，利用氮吸附/解吸等温线来评估AlNi-LDH/CS的结构性质。Al/Ni-LDH/CS表面的比表面积为71.95 m/g，平均孔径为2.537 nm，与片状颗粒的外表面一致。本研究还考察了剂量、pH值、温度和初始浓度对吸附过程的影响。通过平衡吸附和吸附动力学研究了吸附特性。吸附过程符合准二级动力学模型和朗缪尔等温线模型。主要的吸附过程为化学吸附，吸附能为28.42 kJ·mol。温度升高时金属吸附量增加，表明吸附过程是吸热且自发的。利用Box-Behnken设计软件确定了最佳吸附参数，即pH值为5，每25 mL溶液中AlNi-LDH/CS的用量为0.2 g，对砷酸铅溶液的吸附容量为453.05 mg/g。对于复合海绵在吸附砷酸盐以及用于水净化过程中最有效而言，这些因素至关重要。通过应用Design-Expert软件的Box-Behnken设计和响应面技术，经过少量有计划的试验成功改进了吸附过程。通过连续六个吸附和解吸循环对吸附剂的可重复使用性进行评估，证实了其稳定性，且去除效率没有明显下降。此外，它在重复使用前后保留了原始化学成分，展示了一致的效率，并保持了均匀的XRD数据。
