基于ZIF-9的多孔碳对次甲基绿的吸附动力学研究

以含钴的类沸石咪唑酯骨架结构材料ZIF-9为模板,在氩气中进行碳化,以及在碳化时加入硫粉,分别得到含钴和钴硫双掺杂的多孔碳材料Co/C-700和CoS/C-700.对合成材料的结构和组成进行了PXRD、Raman光谱、SEM和氮气吸附脱附的表征,结果显示:合成材料保持了模板的骨架结构,比表面积分别为270.59和108.78 m2·g-1,是微孔介孔碳纳米复合材料.Co/C-700和CoS/C-700对染料次甲基绿的最大吸附量分别为58.31和57.90 mg·g-1,吸附符合准二级动力学模型、孔扩散模型和Langmuir模型.分离、再生以及循环使用4次之后的Co/C-700对次甲基绿的吸附率仅下降了4%.

Kinetic studies of ZIF-9-derived porous carbons on the adsorption of methylene green

A zeolite imidazole framework materials ZIF-9 was used as sacrifice template for the direct synthesis of Co-doped porous carbon material Co/C-700 by 700 ℃ pyrolysis in argon. Co and S dual-doped CoS/C-700 was synthesized according to the identical method. The structure and composition of systhesized materials were characterized by PXRD, Raman spectra, SEM and N2 adsorption. The results shown that as-synthesized materials retain the similar shape and the porous structure as the ZIF-9 precursors. The Brunauer-Emmett-Teller(BET) surface areas of Co/C-700 and CoS/C-700 are 270.59 and 108.78 m2·g-1, respectively, and the materials are classified as micro-and meso-porous materials. The maximum adsorption of methylene green on Co/C-700 and CoS/C-700 were 58.31 and 57.90 mg·g-1, respectively. It is in accordance with the quesi second kinetic model, pore diffusion model and Langmuir model.Reusability tests of Co/C-700 toward methylene green were conducted for 4 cycles, and the adsorption efficiency decreased by about 4% but remained at a high removal efficiency.