Peng Xiong, Liu Shujun, Luo Zhijia, Yu Xiwen, Liang Wanwen
School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China.
School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
Materials (Basel). 2022 Dec 25;16(1):184. doi: 10.3390/ma16010184.
Exploiting an adsorbent with superb selectivity is of utmost importance for the remediation of Cr (VI)-laden wastewater. In this work, a novel nitrogen and sulfur functionalized 3D macroporous cellulose material (MPS) was prepared by homogeneous cross-link cellulose and polyvinylimidazole, followed by ion exchange with MoS. MPS exhibited high removal efficiency at a broad pH range (1.0-8.0) and large adsorption capacity (379.78 mg/g) toward Cr (VI). Particularly, outstanding selectivity with an enormous partition coefficient (1.01 × 10 mL/g) was achieved on MPS. Replacing MoS with Cl and MoO led to a sharp decline in adsorption selectivity, demonstrating that MoS contributed substantially to the selectivity. Results of FTIR, XPS, and apparent kinetic analysis revealed that Cr (VI) was first pre-enriched on the MPS surface via electrostatic and dispersion forces, and then reacted with MoS to generate Cr (III), which deposited on MPS by forming Cr(OH) and chromium(III) sulfide. This study provides a new idea for designing adsorbents with a superior selectivity for removing Cr (VI) from sewage.
开发具有超高选择性的吸附剂对于含铬（VI）废水的修复至关重要。在这项工作中，通过将纤维素与聚乙烯基咪唑均匀交联，随后与MoS进行离子交换，制备了一种新型的氮硫功能化三维大孔纤维素材料（MPS）。MPS在较宽的pH范围（1.0 - 8.0）内表现出高去除效率，对铬（VI）的吸附容量大（379.78 mg/g）。特别地，MPS实现了具有巨大分配系数（1.01×10 mL/g）的出色选择性。用Cl和MoO替代MoS导致吸附选择性急剧下降，表明MoS对选择性有很大贡献。傅里叶变换红外光谱（FTIR）、X射线光电子能谱（XPS）和表观动力学分析结果表明，铬（VI）首先通过静电和分散力在MPS表面预富集，然后与MoS反应生成铬（III），铬（III）通过形成Cr(OH)和硫化铬（III）沉积在MPS上。本研究为设计具有卓越选择性的吸附剂以从污水中去除铬（VI）提供了新思路。
