Sheikhmali Mostafa, Jalilnejad Elham, Rafiee Reza
Faculty of Chemical Engineering, Urmia University of Technology, Urmia, 17165‑57166, Iran.
Sci Rep. 2024 Dec 28;14(1):31083. doi: 10.1038/s41598-024-81982-y.
In this research, 3-(trimethoxysilyl)propyl methacrylate (MPS) silane agent was applied to modify the extracted wheat straw (WS) cellulose as a natural biopolymer. Polyacrylonitrile (PAN) was attached to the MPS-modified WS (MPS-WS) via in-situ polymerization to form PAN-WS biocomposite. AO-WS amidoximated biocomposite adsorbent was synthesized through amidoxime reaction and the effects of different parameters including agitation speed, metal ion concentration, and adsorbent dosage on its efficiency of Pb(II) removal were investigated using the Taguchi experimental design method. The adsorbent was characterized using FE-SEM, FTIR, XRD, and TGA. The FTIR results confirmed that the alkaline treatment removed the hemicellulose and lignin groups and that the silane agent successfully bonded to the WS cellulose. The thermal stability of WS was enhanced by the MPS-WS composite due to the attachment of acrylonitrile polymer chains. The ANOVA results indicated that increasing the adsorbent dosage and decreasing the pollutant's initial concentration significantly improved the adsorption efficiency. The optimal conditions (an agitation speed = 400 rpm, C = 60 mg/L, an adsorbent amount = 0.1 g) yielded maximum adsorption capacity of 22.26 mg/g for the AO-WS bioadsorbent. The kinetic and isotherm studies revealed that the pseudo-second-order kinetic model and the Dubinin-Radushkevich isotherm fit the experimental data best.
在本研究中，使用甲基丙烯酸3-(三甲氧基硅基)丙酯（MPS）硅烷试剂对提取的小麦秸秆（WS）纤维素进行改性，小麦秸秆纤维素是一种天然生物聚合物。通过原位聚合将聚丙烯腈（PAN）附着到MPS改性的WS（MPS-WS）上，形成PAN-WS生物复合材料。通过偕胺肟化反应合成了AO-WS偕胺肟化生物复合吸附剂，并采用田口实验设计方法研究了搅拌速度、金属离子浓度和吸附剂用量等不同参数对其去除Pb(II)效率的影响。使用场发射扫描电子显微镜（FE-SEM）、傅里叶变换红外光谱仪（FTIR）、X射线衍射仪（XRD）和热重分析仪（TGA）对吸附剂进行了表征。FTIR结果证实，碱处理去除了半纤维素和木质素基团，并且硅烷试剂成功地与WS纤维素结合。由于丙烯腈聚合物链的附着，MPS-WS复合材料提高了WS的热稳定性。方差分析结果表明，增加吸附剂用量和降低污染物初始浓度可显著提高吸附效率。最佳条件（搅拌速度 = 400 rpm，C = 60 mg/L，吸附剂用量 = 0.1 g）下，AO-WS生物吸附剂的最大吸附容量为22.26 mg/g。动力学和等温线研究表明，伪二级动力学模型和杜宾宁-拉杜舍维奇等温线最符合实验数据。
