化工进展
化工進展
화공진전
CHEMICAL INDUSTRY AND ENGINEERING PROGRESS
2014年
10期
2546-2551
,共6页
欧阳少波%徐绍平%张俊杰%丛媛媛
歐暘少波%徐紹平%張俊傑%叢媛媛
구양소파%서소평%장준걸%총원원
吸附剂%氮气%甲烷%分离%等温线%热力学%动力学
吸附劑%氮氣%甲烷%分離%等溫線%熱力學%動力學
흡부제%담기%갑완%분리%등온선%열역학%동역학
adsorbent%nitrogen%methane%separation%isotherm%thermodynamics%kinetics
对 N2/CH4在11种不同商业吸附剂上的动态吸附行为进行了研究。通过吸附平衡、吸附热力学和吸附动力学分析了它们对N2/CH4的吸附分离特性,得到了N2和CH4在各吸附剂上的吸附平衡、吸附热力学和吸附动力学基础数据。通过Langmuir吸附模型和Freundlich吸附模型对N2和CH4在吸附剂上的吸附平衡数据进行线性拟合时发现,对于微孔性活性炭两种模型都能达到较好的拟合结果,而对非炭质吸附剂或非微孔性炭质吸附剂拟合结果并不理想;采用Gibbs方程计算得到的吸附剂对吸附N2和CH4的ΔG都小于0,说明所选吸附剂对N2和CH4的吸附都是自发的过程,对于炭质吸附剂吸附CH4的ΔG小于吸附N2的ΔG,说明炭质吸附剂对CH4的吸附能力较N2要大,且CH4/N2的分离系数与吸附剂对吸附CH4和N2的ΔG差值之间也存在相关性;CH4/N2在AC1上的吸附行为符合准二级动力学模型,说明CH4在吸附剂AC1上的吸附行为由表面吸附过程控制。
對 N2/CH4在11種不同商業吸附劑上的動態吸附行為進行瞭研究。通過吸附平衡、吸附熱力學和吸附動力學分析瞭它們對N2/CH4的吸附分離特性,得到瞭N2和CH4在各吸附劑上的吸附平衡、吸附熱力學和吸附動力學基礎數據。通過Langmuir吸附模型和Freundlich吸附模型對N2和CH4在吸附劑上的吸附平衡數據進行線性擬閤時髮現,對于微孔性活性炭兩種模型都能達到較好的擬閤結果,而對非炭質吸附劑或非微孔性炭質吸附劑擬閤結果併不理想;採用Gibbs方程計算得到的吸附劑對吸附N2和CH4的ΔG都小于0,說明所選吸附劑對N2和CH4的吸附都是自髮的過程,對于炭質吸附劑吸附CH4的ΔG小于吸附N2的ΔG,說明炭質吸附劑對CH4的吸附能力較N2要大,且CH4/N2的分離繫數與吸附劑對吸附CH4和N2的ΔG差值之間也存在相關性;CH4/N2在AC1上的吸附行為符閤準二級動力學模型,說明CH4在吸附劑AC1上的吸附行為由錶麵吸附過程控製。
대 N2/CH4재11충불동상업흡부제상적동태흡부행위진행료연구。통과흡부평형、흡부열역학화흡부동역학분석료타문대N2/CH4적흡부분리특성,득도료N2화CH4재각흡부제상적흡부평형、흡부열역학화흡부동역학기출수거。통과Langmuir흡부모형화Freundlich흡부모형대N2화CH4재흡부제상적흡부평형수거진행선성의합시발현,대우미공성활성탄량충모형도능체도교호적의합결과,이대비탄질흡부제혹비미공성탄질흡부제의합결과병불이상;채용Gibbs방정계산득도적흡부제대흡부N2화CH4적ΔG도소우0,설명소선흡부제대N2화CH4적흡부도시자발적과정,대우탄질흡부제흡부CH4적ΔG소우흡부N2적ΔG,설명탄질흡부제대CH4적흡부능력교N2요대,차CH4/N2적분리계수여흡부제대흡부CH4화N2적ΔG차치지간야존재상관성;CH4/N2재AC1상적흡부행위부합준이급동역학모형,설명CH4재흡부제AC1상적흡부행위유표면흡부과정공제。
The N2/CH4 dynamic adsorption behaviors in eleven commercial adsorbents were investigated. The N2/CH4 separation properties of the adsorbents were discussed by adsorption equilibrium,adsorption thermodynamics and adsorption kinetics,from which the correlation coefficients of adsorption equilibrium,adsorption thermodynamics and adsorption kinetics for N2 and CH4 on the adsorbents were obtained. With Langmuir adsorption model and Freundlich adsorption model,the liner fittings were performed for the N2 and CH4 adsorption equilibrium data. It was found that for the microporous activated carbons,the data could be well fitted by both models,while the linear fitting was an unsatisfactory for non-carbonaceous adsorbents and non-microporous carbon adsorbents. With Gibbs adsorption equation,the N2 and CH4 Gibbs free energies adsorbed in the adsorbents were all below zero, suggesting that the N2 and CH4 adsorption processes in the adsorbents were spontaneous. For carbon adsorbents,the difference of CH4 and N2 Gibbs free energies was lower than zero,indicating that carbon adsorbents had stronger adsorption on CH4 adsorbed than N2. At the same time,there was a certain relation of the CH4/N2 separation factor (α)of the adsorbents and the difference of CH4 and N2 Gibbs free energies. For adsorption kinetics,CH4 adsorption kinetic process in AC1 was studied at different adsorption pressures. The data could be well described with the pseudo-second order kinetic model,indicating that the surface adsorption was the rate-determining process during the process of CH4 adsorption in AC1.