磷酸钛作为气相色谱固定相的机理探讨

Investigation on the Mechanism for Titanium Phosphate as the Packings in Gas Chromatography

从热力学和动力学角度分析了用不同形态的无机离子交换剂磷酸钛作为气固色谱固定相的分离机理。通过测定被分离有机物在不同柱上的吸附热和熵变，认为在分离过程中并不存在因微晶形磷酸钛的层状结构而产生的分子筛机理，而主要是由吸附作用决定的。测定不同类型的有机物在该类柱上的柱效能及进样量与保留的关系，认为色谱峰扩张主要是由于气相及吸附相传质阻力而引起。微晶形磷酸钛较无定形磷酸钛有较好的分离能力。

Bsed on the standpoint of thermodynamics and kinetics,the separation mechanism for tita-nium phosphate under different states on the gas-sdid Chromatographic pakings is investigated. Bydeterminming both the absorption heat and the entropy entropy change , it was found that the tradi-tional molecular sieve mechanism , due to the layer structure of microcrystalline titanium phosphate,does not exsit in the Separetion process. And the mechanism may be mainly dominated by the absorp-tion effect. Also,by studying the cllumn effency and the ralationship between the sample size and theretention,it is concludeed that the peak spreding mainly comes from the resistance of mass transfer inthe chromatographic process.