碳沉积时间对煤层气提纯用碳分子筛性能的影响研究  

Effects of carbon deposition time on carbon molecular sieves for purification of coal-bed methane

作　　者：傅翔 FU Xiang(Beijing Research Institute of Coal Chemistry,China Coal Research Institute Corporation Ltd.,Beijing 100013,China;Beijing Key Laboratory of Coal Based Carbon Materials,Beijing 100013,China;State Key Laboratory of Coal Mining and Clean Utilization,Beijing 100013,China)

机构地区：[1]煤炭科学技术研究院有限公司煤化工分院,北京100013 [2]煤基节能环保炭材料北京市重点实验室,北京100013 [3]煤炭资源高效开采与洁净利用国家重点实验室,北京100013

出　　处：《煤质技术》2021年第4期30-34,共5页Coal Quality Technology

基　　金：国家自然科学基金资助项目(U1610221)。

摘　　要：通过制备合适孔径的碳分子筛可实现甲烷与氮的有效分离,借助变压吸附分离工艺提浓再利用将会使我国的煤层气资源利用率大幅提高。采用气相碳沉积法,以煤基活性炭为前驱体、甲苯为沉积剂,调节活性炭孔径制备不同性能的碳分子筛吸附剂,并考察碳沉积时间对制备的碳分子筛样品CH_(4)/N_(2)吸附分离性能以及孔结构的影响。结果表明:通过调整碳沉降时间,可改变CH_(4)、N_(2)在碳分子筛上的吸附量和分离选择性。饱和吸附容量和平衡分离系数均随着碳沉积时间的延长呈先增加后减小的趋势,在碳沉积时间50 min时饱和吸附量达到最大,CH_(4)最大吸附容量达到1.41 mmol/g;在碳沉积时间70 min时,CH_(4)/N_(2)平衡分离系数达到4.74,碳沉积时间70 min性能最优;氮气吸脱附等温线表明碳沉积时间50 min~70 min时,可实现孔口的有效堆积并在缩小孔径的同时形成微孔炭材料。Through preparation of carbon molecular sieves with suitable pore diameter,the effective separation of methane from nitrogen can be achieved,by PSA separation and concentration increasing technology,the utilization ratio of coal bed methane resource will be improved significantly.Using vapor-phase carbon deposition method,taking coal-based activated carbon as precursor and toluene as a deposition agent,carbon molecular sieves were prepared by adjusting the pore size of coal-based activated carbon.The effects of carbon deposition time on adsorption and separation performance and pore structure of carbon molecular sieve sample CH_(4)/N_(2) were investigated.The results show that the adsorption capacity and selectivity of separation of CH_(4)/N_(2) will be changed on carbon molecular sieves by adjusting the carbon deposition time.The saturated adsorption capacity and equilibrium separation coefficients increase firstly and then decrease along with the extension of carbon deposition time.When the carbon deposition time is 50 min,the saturated adsorption amount reaches the maximum value.CH_(4) adsorption capacity is 1.41 mmol/g,the separation coefficient of CH_(4)/N_(2) is 4.74 when the carbon deposition time is 70 min,carbon deposition time of 70 min indicates an optimal performance.The nitrogen adsorption and desorption isotherm shows that the effective accumulation of orifice can be realized when the carbon deposition time is 50 min~70 min,and the pore size can be reduced and the microporous carbon material can be formed at the same time.

关 键 词：碳分子筛 碳沉积 吸附分离 煤层气 微孔炭材料 吸附容量 平衡分离系数 

分 类 号：TQ028.15[化学工程]