Study On Chromatographic Analysis Of Key Impurities In High Purity Hydrogen For Hydrogen Fuel Cell

The quality of hydrogen is closely related to the life of hydrogen fuel cell.Compared with gasoline engine,fuel cell vehicle needs higher purity fuel to prevent the degradation of fuel cell system,so the detection of hydrogen purity in hydrogen fuel cell is particularly important.In order to improve the standard system of hydrogen energy and fuel cell analysis in China,it is of great significance to develop the impurity reference materials in hydrogen and establish the impurity analysis method in hydrogen fuel cell.In this paper,by selecting appropriate gas chromatography,the research contents and results of partial impurity detection in hydrogen are as follows:1.10 kinds of gas reference materials were prepared by weight method,including nitrogen in hydrogen,carbon dioxide in hydrogen,methane in hydrogen,carbon monoxide in hydrogen,helium in hydrogen,carbon monoxide in hydrogen,carbon dioxide,methane mixture,argon in hydrogen,nitrogen,helium mixture,argon in hydrogen,nitrogen mixture and nitrogen and oxygen mixture in hydrogen.Three bottles of standard gas with similar concentration were prepared for each impurity.The uncertainty of the analytical method was 0.3%.2.According to the requirements of ISO 14687 for impurities in hydrogen,a gas chromatograph with high sensitivity is selected.By optimizing the chromatographic analysis conditions,the best analytical method for the detection of impurities is established.The repeatability of the method is less than 1%,which lays the foundation for the development of high-precision reference materials..In addition,Agilent portable gas chromatograph is used to detect helium,argon and Nitrogen Standard Gases in hydrogen on line.The experimental results are good,and the repeatability can be less than 0.5%.The analysis equipment has the advantages of small size and fast detection speed,which can effectively shorten the analysis and detection time.3.Under the optimized chromatographic conditions,trace carbon monoxide,carbon dioxide and methane of the same concentrationin different matrix gases are quantitatively analyzed to select the inert gas which can replace the hydrogen in the matrix gases,so as to facilitate the subsequent determination.4.Dilute the prepared three bottles of carbon monoxide,methane and carbon dioxide mixture through the dilution device,detect the dilution gas(high purity hydrogen)and trace impurities with three different concentrations in the methane converter with the hydrogen flame ionization detector of gas chromatography,and then infer the contents of methane,carbon monoxide and carbon dioxide in the dilution gas by the standard addition method.The results are as follows:methane concentration is 3nmol/mol,carbon monoxide is 2nmol/mol,carbon dioxide is 6nmol/mol.The content of trace related impurities in hydrogen is confirmed by this method,which provides necessary information for the development of gas reference materials.