Department of Organic Chemistry, Bioorganic Chemistry and Biotechnology, Silesian University of Technology, B. Krzywoustego 4, 44-100, Gliwice, Poland; School of Advanced Chemical Sciences, Shoolini University, Solan, 173229, Himachal Pradesh, India.
School of Advanced Chemical Sciences, Shoolini University, Solan, 173229, Himachal Pradesh, India.
Chemosphere. 2022 Mar;291(Pt 3):133002. doi: 10.1016/j.chemosphere.2021.133002. Epub 2021 Nov 26.
Removal of hazardous herbicides from the aqueous solution is critical for overcoming health-related issues across the wider population. In the current work, we have prepared sodium alginate (SAlg), dextrin, and acrylic acid (AA) based cross-linked hydrogels, composed of bentonite incorporated in the biocompatible hydrogel matrix. This hydrogel composite can remove highly toxic herbicide paraquat (PQ). As-synthesised hydrogel (SAlg/dextrin-cl-PAA) and hydrogel composite (SAlg/dextrin-cl-PAA/bentonite) were further analysed by infra-red spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and thermogravimetric analysis (TGA/DSC). For the first time, PQ adsorption onto sodium and dextrin-based hydrogel was also evaluated. The measured highest removal capacities were 76.923 and 90.909 mg g for the SAlg/dextrin-cl-PAA and SAlg/dextrin-cl-PAA/bentonite, respectively. Pseudo-second-order (PSO) and Langmuir isotherm models have shown to be best suited for accurately describing the adsorption mechanism. A thermodynamics study verified that the adsorption of PQ on adsorbents is spontaneous, favourable and exothermic. Moreover, reusability analysis shows that the adsorbents possess good reproducibility even after six successive cycles. The adsorption results demonstrate that the synthesised adsorbents are very efficient for removing herbicides (PQ) from wastewater.
从水溶液中去除有害除草剂对于克服更广泛人群的健康问题至关重要。在目前的工作中，我们制备了基于海藻酸钠（SAlg）、糊精和丙烯酸（AA）的交联水凝胶，由掺入生物相容性水凝胶基质中的膨润土组成。这种水凝胶复合材料可以去除剧毒除草剂百草枯（PQ）。合成的水凝胶（SAlg/dextrin-cl-PAA）和水凝胶复合材料（SAlg/dextrin-cl-PAA/膨润土）进一步通过红外光谱（FTIR）、X 射线衍射（XRD）、场发射扫描电子显微镜（FESEM）和热重分析（TGA/DSC）进行了分析。首次还评估了 PQ 在基于钠和糊精的水凝胶上的吸附。测量的最高去除容量分别为 76.923 和 90.909 mg/g，用于 SAlg/dextrin-cl-PAA 和 SAlg/dextrin-cl-PAA/膨润土。拟二级（PSO）和 Langmuir 等温线模型被证明非常适合准确描述吸附机制。热力学研究证实，吸附剂上 PQ 的吸附是自发的、有利的和放热的。此外，可重复使用性分析表明，即使经过六次连续循环，吸附剂也具有良好的重现性。吸附结果表明，所合成的吸附剂非常有效地从废水中去除除草剂（PQ）。
