煤直接液化生成气气相色谱分析条件研究

为更好地开发利用煤直接液化生成气,必须准确测定煤直接液化生成气各组分含量,分析了气相色谱法测定煤直接液化生成气组成的主要影响因素,如色谱柱程序升温方式、取样袋的选择和分流比的确定,确定最优的试验条件,建立了煤炭直接液化生成气组分分析的标准方法。结果表明,采用气相色谱法测定煤直接液化生成气的组分含量的最佳分析条件为:采用以15℃/min的升温速度从60℃升温至150℃,始温保持10 min,终温保持4 min的升温程序;复合膜取样袋取样;与FID相联的用于烃类分析,与TCD相连的用于无机气体分析,其载气均为氦气,流速为38 m L/min;有机烃气路分流比为50∶1,无机气体气路不分流。将标准气体进行8次平行分析表明,气相色谱法的相对误差不大于3.5%,样品回收率均在97%~102.03%,准确度和精密度良好,说明气相色谱条件适于分析煤直接液化生成气含量。

Study on the gases compositions analysis of direct coal liquefaction by gas chromatography

In order to make better utilization of the gaseous products of direct coal liquefaction,their components should be accurately determined.The factors influencing on the measurement were systematically studied.The gas chromatography was adopted to analyze the gases components of direct coal liquefaction,and the optimum analysis conditions were determined according to the results,that is,the temperature raises from 60 ℃ to 150 ℃ at a rate of 15 ℃/min,and the initial and final temperatures are holding for 10 min and 4 min,respectively.Tedlar gas sampling bags are the best materials.The gases are divided into hydrocarbons and permanent gases,which are analyzed by the FID and TCD detectors,respectively,while helium is used as carrier gas at a rate of 38 mL/min.The split ratio of capillary column is 50:1,and molecular sieve columns are without splitting.The relative deviation of 8 times repeated measurements are less than 3.5％ and the recoveries are 97％ ～ 102.03％ indicating high precision and better repeatability of such method.