用火焰光度计、原子吸收光度计、原子荧光光谱仪等仪器进行火焰光谱分析时,常以乙炔作为燃料气体。而乙炔往往是由水作用于电石来制备的。因而,在乙炔中常常含有电石带来的杂质:磷化氢、硫化氢、硅化氢、氨、氢、甲烷和拌随着气流一道吹出来的固体氧化钙微粒及水蒸气。在一般情况下,这些杂质中的全部氨、氧化钙微粒和大部分硫化氢都可经水洗而除去。剩余的杂质主要是磷化氢对火焰光谱构成明显的干扰,在乙炔-空气焰中,特别是高温乙炔-氧气焰 Flame photometer, atomic absorption spectrophotometer, atomic fluorescence spectrometer and other instruments for flame analysis, often with acetylene as fuel gas. Acetylene is often prepared by the action of water on calcium carbide. Thus, acetylene often contain calcium carbide impurities: phosphine, hydrogen sulfide, hydrogen sulfide, ammonia, hydrogen, methane and mix with the airflow blowing out of the solid calcium oxide particles and water vapor. In general, all of the ammonia, calcium oxide particles and most of the hydrogen sulfide in these impurities can be removed by washing with water. The remaining impurities are mainly phosphine gas flame constitute a clear interference, in the acetylene - air flame, especially the high temperature acetylene - oxygen flame