煤质技术2023，Vol.38Issue(6)：66-73,79,9.DOI:10.3969/j.issn.1007-7677.2023.06.009
基于分离CH4/N2用碳分子筛的特性表征方法及吸附评价
Characterization and adsorption evaluation of CH4/N2 separation by carbon molecular sieve
摘要
Abstract
Establishing a unified characterization method and evaluation system for carbon molecular sieves used in CH4/N2 pressure swing adsorption is beneficial for objectively evaluating the performance of adsorbents and guiding the selection and preparation of carbon molecular sieves for separating CH4/N2.Typical carbon molecular sieve sam-ples with better separation efficiency were selected,and the pore structure of the samples was observed using nitrogen adsorption desorption method,through X-ray diffraction and X-ray photoelectron spectroscopy,the surface elemental composition and chemical state of the sample were characterized.Utilizing self-made high-pressure adsorption equip-ment,thermogravimetric analyzer and pressure swing adsorption device,the sample equilibrium adsorption,kinetic adsorption,and pressure swing adsorption performance were experimentally researched.The results show that,the micro pores in carbon molecular sieves play a crucial separation role,the separation performance evaluation should be carried out based on the combination of pore volume and pore size distribution;the oxygen-containing functional groups on the surface of carbon molecular sieves can form active centers,the adsorption and separation of samples can be promoted.When the CH4/N2 equilibrium adsorption separation ratio is greater than 3,the effective separation of CH4/N2 in coalbed methane can be achieved.According to the kinetic adsorption of the sample,the adsorption rate of N2 in the initial stage of adsorption is significantly higher than that of CH4,PSA can be used to separate CH4/N2.Evaluating the strength and pressure swing adsorption when selecting carbon molecular sieves can determine whether commercial carbon molecular sieves can be used.When preparing carbon molecular sieves,pore size analysis can be combined to guide the carbonization,activation,and pore size adjustment steps during the preparation process.Based on the surface chemical properties,the selection of raw materials for preparation and pre oxidation process can be guided.The adsorption capacity and separation performance of carbon molecular sieve can be obtained through ad-sorption evaluation,and then its service life can be further evaluated through strength testing.关键词
碳分子筛/特性表征方法/性能评价/孔隙结构/表面化学性质/平衡吸附/动力学吸附/活性中心Key words
carbon molecular sieve/characteristic characterization methods/performance evaluation/pore struc-ture/surface chemical properties/equilibrium adsorption/dynamic adsorption/active center分类
化学工程引用本文复制引用
车永芳,马克富..基于分离CH4/N2用碳分子筛的特性表征方法及吸附评价[J].煤质技术,2023,38(6):66-73,79,9.基金项目
天地科技股份有限公司科技创新创业资金青年资助项目(2022-2-TD-ON003) （2022-2-TD-ON003）
