CO2-hierarchical activated carbon prepared from coal gasification residue:Adsorption equilibrium, is

• 作 者: Yuhong Kang Xianyong Wei Guanghui Liu Miao Mu Xiangrong Ma Yong Gao Zhimin Zong
• 机 构: Key Laboratory of Coal Processing and Efficient Utilization, Ministry of Education, China University
• 出 处: 中国化学工程学报（英文版）
• 发表日期: 2020年6期
• 关键词: Residue from coal gasification Hierarchical activated carbon Physical activation

Mineral matter in a residue (RCG) from coal gasification (CG) was removed by two-stage acid leaching. Hierarchical activated carbon (HAC) was prepared by activating RCG with CO2. The performance of HAC on removing methylene blue (MB) from an aqueous solution was investigated. HAC was characterized by N2 adsorption–desorption iso-therm, Fourier transform infrared spectroscopy, and scanning electron microscopy. The results show that HAC ex-hibits hierarchical pore structure with high specific surface area (862.76 m2·g?1) and total pore volume (0.684 cm3·g?1), and abundant organic functional groups. The adsorption equilibrium data of MB on HAC are best fitted to the Redlich-Peterson. The kinetic data show that the pseudo-first-order model is more suitable at low MB concentration, while the advantages of the pseudo-second-orderand the Elovich models are more obvious as the concentration increases. According to the thermodynamic parameters, the HAC-MB adsorption process is spontaneous and endothermic.