气相色谱法测定煤气中硫化氢含量的研究

Research of detecting hydrogen sulfide in coal gas by gas chromatograph method

对气相色谱法测定煤气中硫化氢含量进行了系统研究,采用高惰性的聚氟乙烯(PVF)气体采样袋替代湿式气体流量计和吸收瓶,简化了采样操作。采用60 m低硫毛细管色谱柱和FPD检测器,分离、分析了焦炉煤气中H_2S、COS、CS_2、噻吩四种主要硫化物。采用优化的VI进样口和特殊的硫钝化管线,提高了仪器灵敏度,方法检出限可达1mg/Nm^3。采用多点校正及二次曲线拟合,测量范围从10 mg/Nm^3到300 mg/Nm^3,并与碘量法测定煤气中硫化氢进行比对,经过精密度试验,准确度验证,证明此方法简便快捷、准确可靠,满足痕量分析的要求。

This paper provides an overview of systematic research of detecting the content of hydrogen sulfide in the coal gas by gas chromatograph method.The sampling operation is simplified by using gas sampling bags made of inert poly vinylfluoride instead of the wetted gas flow meters and absorption bottles.The chief sulfides such as hydrogen sulfide,Carbonyl sulfide,carbon disulfide and thiophene are separated and analyzed by use of 60m low sulphureous capillary chromatograph column and flame photometric detector (FPD).VI injector ports and sulphur passivation pipeline are used to improve the sensitivity of the instrument.The low limit of the method reaches 1mg/Nm3.Multipoint calibration and Quadratic Curve Fitting are taken to enhance the measuring range from 10 mg/Nm3to 300 mg/Nm3.The precision test and accuracy verification are carried out by comparing it with iodine quantity method to prove that the method is accurate,quick and simple,it can meet the requirements of trace analysis.