| The modification of zeolite is carried on for various purposes, especiallyfor improving the adsorption effect. At present, the means of modification onzeolite are plentiful, and the same as the characterization ways. And even if themost complicated characterization means still have their disadvantages andcannot evaluate the zeolite thoroughly and precisely. Gas chromatography isused in this field for its simplicity and acceptable accuracy. Traditionalcharacterization means on zeolite is focused on their thermodynamic propertiesand have difficulities on determining the dynamic properties. In this paper,parameters of adsorption thermodynamic properties and the diffusion coefficientof adsorption dynamic properties and the parameters of mass transferring aboutO2, N2 and CO on three series of zeolite are determined. And the three series ofzeolite are different exchange degree of Ca2+, different activation temperatureand different granularity, respectively. Then, the regularity of the determinedparameters is explained depending on the structure of zeolite. The mainconclusions are following:(1) According to the formula about parameters of adsorption thermodynamics (ΔadH,ΔadS,ΔadG) and adjustment retention time, the paramerters ofadsorption thermodynamics about O2, N2 and CO on A type of zeolite, whoseexchange degree of Ca2+ are different, are determined and calculated by gaschromatography. The results show that: Granularity and the gas velocity have noeffection on parameters of adsorption thermodynamics.the adsorption heat of O2, N2 and CO on zeolite increases along with the increase of exchange degree ofCa2+, and the adsorption heat ranged from-26 kJ·mol-1 to-7.8 kJ·mol-1. Whenthe activation temperatures are 450℃and 650℃, the zeolite have the biggestvalues of adsorption entropies of O2, N2 and CO on the zeolite. The relativity ofall data is considerable well, about 0.999.(2) The O2, N2 and CO on A type of zeolite with different Ca2+ exchangedegree and different activation temperature are determined for the axial diffusioncoefficient, the total mass transfer resistance, et al. The relative coefficient of thedata is well. The results show that: it has small inner pore diameter in zeolitewhen Ca2+ exchange degree is low, and total mass transfer resistance value of O2,N2 and CO on zeolite is high. Although the inner pore diameter increase with theincrease of Ca2+ exchange degree, field intensity in zeolite grew into major facorof affecting total mass transfer resistance when Ca2+ exchange degree is high,and total mass transfer resistance value of O2, N2 and CO on zeolite is also high.With the increase of adsorption temperature, the axial diffusion coefficient valuebecomes higher and the total mass transfer resistance value becomes lower. Thisis because field intensity in zeolite affects the movement of gas molecule weakerand weaker with the increase of adsorption temperature. Because of thedifference of the molecular diameter and the polarity of O2, N2 and CO, the axialdiffusion coefficient value of O2 is higher than the one of N2 and CO, and totalmass transfer resistance value of O2 is lower than the one of N2 and.CO.(3) A chromatography experimental method for measuring gas diffusivity in5A zeolite is set up. Moment analysis method is used to analyze each diffusioncoefficient of total mass transfer resistance, and the results show that: theintracrystalline diffusion coefficient value of O2 and N2 are in the same order ofmagnitude as literature value. They are 2.456×10-9 cm2·s-1 and 1.229×10-9cm2·s-1, respectively.
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