摘要
氢在活性炭上的吸附等温线模型是储氢和分离(或纯化)氢气等工程项目的热力学和工程计算基础。Langmuir、Freundlich、Virial和DubininAstakhov方程是用来描述气/固体系吸附等温线最常见的模型。但是它们在大温度范围的适用性从来没有检验过。本文采用77298K、07MPa范围内氢在活性炭上的吸/脱附数据,分别检验了上述四方程式对于实验数据的拟合程度,并以各实验温度下的标准偏差和整个实验范围内的总偏差对各方程的适用性做了定量的比较。结果表明,D-A方程在全部实验条件下的总平均偏差为3.0%,是实验等温线最贴切的模型;Freundlich方程次之,总偏差为3.3%;Langmuir方程在113K以上温度下尚能作为等温线模型,但在更低的温度下绝不适用;Virial方程与其类似,适用范围是153-298K。
The Langmuir equation and one of its modified version, Virial equation and the Dubinin Astakhov equation were fitted to high pressure adsorption isotherms of hydrogen. The isotherms covered the experimental range of 77 ̄298K and 0 ̄7 MPa. Standard deviation of a model from the measured values was used as the criteria to compare the fitness of different models. the D A equation and the modified Langmuir equation fit the experimental isotherms very well in the whole range tested. However, the Langmuir equation and the Virial equation can only be applied above a lower limit temperature. Even for the best fit D A equation, abnormal parameter behavior was observed.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
1998年第3期209-212,共4页
Journal of Chemical Engineering of Chinese Universities
基金
国家自然科学基金
关键词
氢
高压
等温线模型
吸附储氢
活性炭
Hydrogen, Adsorption, High Pressure, Isotherm modeling