Anionic dye uptake via composite using chitosan-polyacrylamide hydrogel as matrix containing TiO2 nanoparticles; comprehensive adsorption studies
Anionic dye uptake via composite using chitosan-polyacrylamide hydrogel as matrix containing TiO2 nanoparticles; comprehensive adsorption studies
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DOI：
10.1016/j.ijbiomac.2020.06.158
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发表时间：
2020-11-01
影响因子：
8.2
通讯作者：
Yuan, Daqiang
中科院分区：
文献类型：
--
作者：
Binaeian, Ehsan;Zadvarzi, Saber Babaee;Yuan, Daqiang
采用原位合成法制备了分散在壳聚糖接枝聚丙烯酰胺基质中的纳米TiO 2（TiO 2-PAM-CS），并将其应用于天狼星黄K-CF染料的吸附。采用FE-SEM、TEM、XRD、FT-IR等手段对复合材料进行了表征。考察了pH值、投加量、时间和温度等因素对吸附效果的影响。吸附过程与pH值有关，最佳pH值为2，在40 ℃时染料去除率为96.81%。平衡数据与q m值为1000 mg/g的Langmuir等温线很好地相容。Dubininin-Radushkevich（D-R）等温线和热力学研究证明吸附是物理的、吸热的和自发的。动力学研究也证实了伪二级动力学模型是主导模型。聚丙烯酰胺-壳聚糖（PAM-CS）复合材料的胺基以NH3+的形式与阴离子染料分子形成氢键（Dye-NH3+），以及PAM-CS复合材料中Ti+4与阴离子染料分子之间的静电相互作用（D-R模型计算自由能为1.66kJ/mol）决定了PAM-CS复合材料的吸附机理。可重复使用性试验表明，TiO 2-PAM-CS复合材料可以很容易地用HCl溶液进行再生，是一种有效的废水处理吸附剂。(c)2020 Elsevier B. V.保留所有权利。
In the present study, TiO2 nanoparticles dispersed in chitosan grafted polyacrylamide matrix (TiO2-PAM-CS) was synthesized using in situ technique, and applied for the uptake of Sirius yellow K-CF dye from aqueous solution. The synthesized nano-composite was characterized by FE-SEM, TEM, XRD and FT-IR analysis. The effect of significant parameters such as pH, dose, time and temperature in batch adsorption experiments were investigated. The adsorption process was pH dependent and the optimum value of pH was obtained 2 with 96.81% dye removal at 40 degrees C. The equilibrium data were compatible well with the Langmuir isotherm having qm value of 1000 mg/g. The Dubinin-Radushkevich (D-R) isotherm and thermodynamic studies prove that the adsorption is physical, endothermic and spontaneous. Kinetic study also verifies that pseudo second order kinetic model is the predominant model. The interactions between amin groups of polyacrylamide-chitosan (PAM-CS) composite in from of NH3+ and molecules of anionic dye via hydrogen bond formation (Dye-NH3+), also electrostatic interactions between Ti+4 available in PAM-CS composite and anionic dye (free energy of 1.66 kJ/mol calculated from D-R model) govern the adsorption mechanism. The reusability test showe that TiO2-PAM-CS composite can be renewed easily with HCl solution as an efficient adsorbent for practical wastewater treatment. (c) 2020 Elsevier B.V. All rights reserved.