Zhao Jiaming, Yu Lihua, Zhou Feng, Ma Huixia, Yang Kongyan, Wu Guang
School of Chemistry and Materials Sciences, Research Institute of Crop Science, Heilongjiang University Harbin 150080 China
Dalian Research Institute of Petroleum and Petrochemicals, SINOPEC Dalian 116045 China.
RSC Adv. 2021 Feb 24;11(14):8025-8032. doi: 10.1039/d0ra09644j. eCollection 2021 Feb 17.
A series of micro-mesoporous activated carbons (ACs) were prepared from sugar beet residue by a two-step method including KOH chemical activation and were used for Cr(vi) removal from aqueous solutions. Several characterization techniques, including SEM, TEM, N adsorption, XRD, FTIR, and Raman spectroscopy, were used to determine the chemical and physical characteristics of the ACs, and the adsorption properties of the ACs were tested. The results indicated that the high specific surface area of the ACs reached 2002.9 m g, and the micropore surface area accounts for 85% of the total area. The optimal conditions for achieving the maximum Cr(vi) adsorption capacity of 163.7 mg g by the ACs were activation with a KOH/carbon ratio of 3.0, an initial Cr(vi) concentration of 400 mg L, an adsorbent dose of 2.0 g L and pH of 4.5. Therefore, the ACs exhibit excellent adsorption performance for removing Cr(vi) from aqueous solutions. According to an investigation of the adsorption process, the adsorption isotherm is most consistent with the Langmuir isotherm model, and the adsorption kinetics were well described by the pseudo-second-order model.
采用两步法，以甜菜渣为原料，通过KOH化学活化制备了一系列微介孔活性炭（ACs），并用于从水溶液中去除Cr(VI)。采用扫描电子显微镜（SEM）、透射电子显微镜（TEM）、N吸附、X射线衍射（XRD）、傅里叶变换红外光谱（FTIR）和拉曼光谱等多种表征技术来确定ACs的化学和物理特性，并测试了ACs的吸附性能。结果表明，ACs的高比表面积达到2002.9 m²/g，微孔表面积占总面积的85%。ACs实现最大Cr(VI)吸附容量163.7 mg/g的最佳条件为：KOH/碳比为3.0进行活化、初始Cr(VI)浓度为400 mg/L、吸附剂剂量为2.0 g/L、pH值为4.5。因此，ACs在从水溶液中去除Cr(VI)方面表现出优异的吸附性能。根据对吸附过程的研究，吸附等温线与朗缪尔等温线模型最为吻合，吸附动力学可用准二级模型很好地描述。
