Journal of Polymers and the Environment ( IF 5.3 ) Pub Date : 2020-03-28 , DOI: 10.1007/s10924-020-01713-y Hemant Mittal , Pranay P. Morajkar , Ali Al Alili , Saeed M. Alhassan
The current study focused on the use of gum Arabic grafted polyacrylamide (GA-cl-PAM) hydrogel as a self-template for the in situ synthesize of zinc oxide nanoparticles (ZnO NPs) and the application of synthesized nanocomposite as a potential adsorbent to remove synthetic dyes especially malachite green (MG) from aqueous solution. Different characterization techniques supported in situ synthesis of ZnO NPs onto polymer matrix. The gum Arabic-crosslinked-poly(acrylamide)/zinc oxide nanocomposites (i.e., GA-cl-PAM/ZnO nanocomposite) exhibited much better surface properties as compared to the parental hydrogel matrix. The swelling abilities of the GA-cl-PAM/ZnO nanocomposites with different concentrations of acrylamide were also checked and the nanocomposite with 7.03 × 10–4 mol/L of acrylamide exhibited maximum swelling capacity of 2354%. The nanocomposite adsorbed approximately 99% MG dye with 0.4 g/L adsorbent dose at neutral pH. Adsorption kinetics and isotherm followed pseudo-second-order and Langmuir isotherm models, respectively with the high adsorption capacity of 766.52 mgd/gads at 25 °C. It was observed that the dye molecules were adsorbed onto GA-cl-PAM/ZnO nanocomposite mostly via electrostatic interactions, hydrogen-bonding and pore-diffusion mechanisms. Diffusion of dye molecules within the internal structure of GA-cl-PAM/ZnO nanocomposite followed the combination of both liquid film as well as intraparticle diffusion mechanisms. Furthermore, nanocomposite was applied ten times consecutively to adsorb MG dye from aqueous solution. Therefore, GA-cl-PAM hydrogel have capability to be used for the in situ ZnO NPs synthesis and thus synthesized nanocomposite can be used effectively to treat dyes polluted wastewater.
中文翻译:
以阿拉伯树胶为基础的水凝胶作为孔雀石绿染料有效吸附的自模板,原位合成ZnO纳米颗粒
当前的研究集中在阿拉伯胶接枝的聚丙烯酰胺(GA-cl-PAM)水凝胶作为原位合成氧化锌纳米颗粒(ZnO NPs)的自模板以及合成的纳米复合材料作为潜在的吸附剂去除水溶液中的合成染料,尤其是孔雀石绿(MG)。不同的表征技术支持将ZnO NPs原位合成到聚合物基质上。与亲本水凝胶基质相比,阿拉伯树胶交联的聚丙烯酰胺/氧化锌纳米复合材料(即GA-cl-PAM / ZnO纳米复合材料)表现出更好的表面性能。还检查了具有不同丙烯酰胺浓度的GA-cl-PAM / ZnO纳米复合材料的溶胀能力,并发现了具有7.03×10 –4的纳米复合材料 mol / L的丙烯酰胺最大溶胀度为2354%。在中性pH值下,纳米复合材料以0.4 g / L的吸附剂吸附了约99%的MG染料。吸附动力学和等温线遵循伪二级和Langmuir等温线模型,分别具有766.52 mg d / g ads的高吸附容量在25°C下。观察到染料分子主要通过静电相互作用,氢键和孔扩散机制吸附到GA-cl-PAM / ZnO纳米复合材料上。染料分子在GA-cl-PAM / ZnO纳米复合材料内部结构中的扩散遵循液膜和颗粒内扩散机制的结合。此外,连续施加十次纳米复合物以从水溶液中吸附MG染料。因此,GA-cl-PAM水凝胶具有用于原位合成ZnO NPs的能力,因此合成的纳米复合材料可以有效地用于处理染料污染的废水。