Determination of transport coefficients in microporous solids
Determination of transport coefficients in microporous solids
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微孔固体中传输系数的测定
DOI：
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
A. Micke
中科院分区：
文献类型：
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作者：
M. Bülow;A. Micke
综述了宏观瞬态方法在微孔吸附体系中分子迁移研究中的适用性。通过批处理方法获得的非平衡吸附结果的数据评估的各种复杂程度被识别和表征。特别注意的是表征的流体（晶内）扩散以及识别和定量的额外的速率机制，通常，可能同时发生在分子筛系统。举例说明了目前最先进的输运系数测定方法，用于mfi型的苯/微孔硅酸盐、正己烷/硅酸盐- i和对乙基甲苯/ZSM-5体系。它们的吸附速率行为可以分别通过菲克扩散或菲克扩散、晶体内分子固定/动员和表面屏障渗透来理解。为了分析微孔系统中复杂的吸附速率模式，必须考虑全参数区域的全曲线拟合方法。
Macroscopic transient methods are reviewed with respect to their applicability to the investigation of molecular transport in microporous sorption systems. Various levels of sophistication of data evaluation for nonequilibrium sorption results obtained by means of batch methods are identified and characterised. Special attention is paid to the characterisation ofFickian (intracrystalline) diffusion as well as to the identification and quantification of additional rate mechanisms that, in general, may simultaneously occur in molecular sieve systems. A state-of-art determination of transport coefficients is exemplified for the systems benzene/microporous gallosilicate of MFI-type, n-hexane/silicalite-I and p-ethyltoluene/ZSM-5. Their sorption rate behaviour can be understood either byFickian diffusion or byFickian diffusion and intracrystalline molecular immobilisation/mobilisation and surface barrier penetration, respectively. To analyse complex sorption rate patterns in microporous systems, the method oftotal curve fitting with full parameter region consideration becomes mandatory.