示波极谱法测定轻质油品中元素硫含量应注意的问题

PAYING ATTENTION TO THE DETERMINATION OF ELEMENTAL SULFUR IN LIGHT DISTILLATES BY OSCILLOSCOPIC POLAROGRAPHY

研究了在示波极谱法测定喷气燃料中元素硫含量的过程中,几种不同类型硫化物对测定结果的影响。结果表明,质量分数在300μg/g以上的硫醇硫严重干扰测定结果,30～300μg/g的硫醇硫对测定结果影响较大,30μg/g以下的硫醇硫和其它类型硫化物对测定结果影响不大。因此,当样品中硫醇硫质量分数高于30μg/g时,必须先将硫醇转化或脱除,再进行元素硫的测定。

Investigation in the interference of different kinds of sulfide with the determination of elemental sulfur in jet fuel was carried on by oscilloscopic polarography. Results showed that when the mercaptan content in jet fuel was in the range of over 300μg/g, between 30-300μg/g, and below 30μg/g, the measuring result was seriously interfered, interfered and basically not interfered, respectively. Other kinds of sulfide, such as ethyl thioether, 2-methylthiophene, 2-ethylthiophene etc. offered no interference. Therefore, to ensure the measuring accuracy when mercaptan content in sample is over 30μg/g, pretreatment is required to transform or remove the mercaptan.