热重分析测定脱附活化能分布研究  

A TGA METHOD FOR THE DETERMINATION OF THE ACTIVATION ENERGY DISTRIBUTION FOR DESORPTION

作　　者：李湘[1] 郭海福[1] 闫鹏[1] 

机构地区：[1]肇庆学院化学化工学院,肇庆526061

出　　处：《离子交换与吸附》2011年第6期555-561,共7页Ion Exchange and Adsorption

基　　金：广东省自然科学基金(No.7010327)

摘　　要：以脱附过程本征动力学模型为基础,提出了一种采用热重分析技术测定脱附活化能随吸附质分子表面覆盖率分布的方法。该方法通过一条热重分析曲线就可以得到清晰的脱附活化能关于覆盖率的函数表达式。采用所提出的方法,通过不同升温速率下的热重分析实验测定了芴和蒽在活性炭上脱附活化能的线性分布,结果表明覆盖率越高,脱附活化能越低。对芴和蒽,由于覆盖率上升,脱附活化能最大降幅达18.5%和15.1%。A method was proposed for determination of the distribution of activation energy for desorption by thermogravimetric analysis based on intrinsic desorption kinetics.Thermogravimetric analysis of fluorene and anthracene desorbed from activated carbon were conducted in a helium stream with different heating rate.By using the proposed methods,a linear relationship of adsorbate coverage and activation energy for desorption was determined.The results showed that the higher the coverage of adsorbate molecules,the lower the activation energy for desorption.For fluorene and anthracene on Norit RB1,the decrease amplitude was up to 18.5% and 15.1%,respectively.

关 键 词：脱附活化能分布 覆盖率 芴 蒽 

分 类 号：O656-33[理学—分析化学]