Laboratory of Organic Solid Waste Treatment and Recycling, College of Materials Science and Engineering, Henan Institute of Technology, Xinxiang 453003, China.
College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China.
Molecules. 2023 Jan 18;28(3):984. doi: 10.3390/molecules28030984.
SO-containing compounds are widely present in wastewater generated from various industries and mining industries, such as slag leachate, pulp and paper wastewater, modified starch wastewater, etc. When the concentration of SO is too high, it will not only be corrosive to metal equipment but also accumulate in the environmental media. Based on this, a novel cationic hydrogel HNM was synthesized in this study by introducing morpholine groups into the conventional hydrogel HEMA-NVP system for the adsorption of SO in aqueous solutions. Characterizations by Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) indicated that morpholine groups had been introduced into the as-synthesizedhydrogels. The scanning electron microscope (SEM) characterization results show that the introduction of morpholine groups changed the surface of the hydrogel from micron-scale wrinkles to nanoscale gaps, increasing the contact area with the solution. The results of static water contact angle (WCA), equilibrium water content (EWC), and SO adsorption capacity show that the introduction of morpholine groups not only further improved the equilibrium water content and hydrophilicity of the hydrogel but also greatly improved the SO adsorption capacity of the hydrogel, with the maximum SO adsorption amount of 21.59 mg/g, which was much higher than that of the hydrogel without morpholine groups of 5.15 mg/g. Further studies found that the adsorption of SO on the hydrogel HNM was pH-dependent, and acidic conditions were favorable for the adsorption. Therefore, the introduction of morpholine groups greatly enhanced the ability of conventional HEMA-NVP hydrogels to remove SO from aqueous solutions.
含硫化合物广泛存在于各种工业和采矿业产生的废水中，如矿渣浸出液、纸浆和造纸废水、改性淀粉废水等。当 SO 的浓度过高时，它不仅会对金属设备具有腐蚀性，而且还会在环境介质中积累。基于此，本研究通过在常规水凝胶 HEMA-NVP 体系中引入吗啉基团，合成了一种新型阳离子水凝胶 HNM，用于吸附水溶液中的 SO。傅里叶变换红外（FTIR）光谱和 X 射线光电子能谱（XPS）的表征表明，吗啉基团已被引入到所合成的水凝胶中。扫描电子显微镜（SEM）的表征结果表明，引入吗啉基团使水凝胶的表面从微米级褶皱变为纳米级间隙，增加了与溶液的接触面积。静态水接触角（WCA）、平衡水含量（EWC）和 SO 吸附容量的结果表明，引入吗啉基团不仅进一步提高了水凝胶的平衡水含量和亲水性，而且大大提高了水凝胶对 SO 的吸附能力，最大 SO 吸附量为 21.59mg/g，远高于未引入吗啉基团的水凝胶的 5.15mg/g。进一步的研究发现，SO 在水凝胶 HNM 上的吸附是依赖于 pH 的，酸性条件有利于吸附。因此，引入吗啉基团大大增强了常规 HEMA-NVP 水凝胶从水溶液中去除 SO 的能力。
