College of Chemical Engineering, Zhejiang University of Technology, 310014 Hangzhou, Zhejiang, China; Biodiesel Laboratory of China Petroleum and Chemical Industry Federation, 310014 Hangzhou, Zhejiang, China; and Zhejiang Province Key Laboratory of Biofuel, 310014 Hangzhou, Zhejiang, China E-mail:
Water Sci Technol. 2020 Mar;81(6):1114-1129. doi: 10.2166/wst.2020.167.
In this study, an efficient route to synthesizing polyethyleneimine-modified ultrasonic-assisted acid hydrochar (PEI-USAH) is developed and reported. Ultrasonic irradiation technique was used as surface modification method to shorten the crosslinking reaction for hydrochar and polyethyleneimine (PEI). The PEI-USAH showed an excellent adsorption capacity for Cr(VI) from aqueous solution. The physicochemical properties of this PEI-modified adsorbent were comparatively characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, Brunauer-Emmett-Teller analysis and CNHS analysis. The effects of contact time, initial pH, and biosorbent dose on adsorption capacities were investigated. The batch adsorption experiments showed that PEI-USAH possessed the maximum adsorption capacities of 94.38 mg/g and 330.84 mg/g for initial Cr(VI) concentration of 100 mg/L and 500 mg/L, respectively. Furthermore, this adsorption process could be fitted to Langmuir adsorption and described by the pseudo second order kinetic model. Based on the above findings, PEI-USAH could be used as a potential adsorbent for removal of Cr(VI) from wastewater.
本研究开发并报道了一种高效的合成聚乙烯亚胺改性超声辅助酸水凝胶（PEI-USAH）的方法。超声辐射技术被用作水凝胶和聚乙烯亚胺（PEI）的表面改性方法，以缩短交联反应。PEI-USAH 显示出从水溶液中对 Cr(VI) 的优异吸附能力。通过傅里叶变换红外光谱、扫描电子显微镜、X 射线光电子能谱、Brunauer-Emmett-Teller 分析和 CNHS 分析对该 PEI 改性吸附剂的物理化学性质进行了比较表征。考察了接触时间、初始 pH 值和生物吸附剂剂量对吸附容量的影响。批量吸附实验表明，PEI-USAH 对初始 Cr(VI)浓度为 100mg/L 和 500mg/L 的吸附容量分别达到 94.38mg/g 和 330.84mg/g。此外，该吸附过程可以拟合 Langmuir 吸附，并可以用伪二级动力学模型来描述。基于上述发现，PEI-USAH 可用作从废水中去除 Cr(VI)的潜在吸附剂。
