费—托合成实验中烷烃气碳同位素分馏机理

40多年来的费—托合成模拟实验表明,只有部分结果出现了烷烃气碳同位素反序现象。通过较为完整的分析发现,其原因可能是:随着模拟实验时间的增加与温度的升高并随着产物转化率的增高,控制烷烃气碳同位素分馏的因素逐渐由动力学机制转变为热力学平衡,烷烃气碳同位素序列将由反序转变为部分倒转再到类似常规天然气的正序分布。只有在较短时间(转化率较低)或者开放体系(随生随排)条件下才遵从动力学分馏。电火花放电合成实验仅代表了理想状态下动力学分馏过程。

Carbon Isotope Fractionation Mechanism of Alkane Gases in Fischer-Tropsch Synthesis Experiments

Fischer-Tropsch synthesis experiments indicate that carbon isotopes of alkane gases reversed in these experiments on occasion.By analyzing the whole process and data of all researchers,the probable interpretations are deduced as fellows.As the products conversion heightening with the experiment time and temperature increasing,the control of alkane carbon isotope fractionation in the experiments was gradually shifted from kinetic mechanism to thermodynamic equilibrium.Series of carbon isotopes of alkane gases were changed from reversed to normally distribution just like alkanes in natural gas.The experiments were controlled by kinetic fractionation on the conditions of short time reaction(low conversion) or in an opened system(discharging following the reaction).And the electric spark synthesis experiment was more an ideal condition delegating the course of carbon isotope fractionation.