氧瓶燃烧-ICP-AES法测定石油化工产品中的硫

根据不同样品选择了适当的燃烧载体,以自制的滤纸柱作为燃烧载体处理柴油样品,克服了样品燃烧速度过快、反应不完全,造成的试验失败问题;以滤纸片作为燃烧载体处理瞬干胶样品,可以有效地降低本底值.选择了仪器最佳工作条件,测定中选择了紫外区的谱线（S 182.034 nm）作分析线,有效避免了基体中的金属元素的干扰.进行11次空白试验,算得方法的检出限为0.019 mg/L;选取3份柴油样品按所提出方法各进行5次分析,算得方法的RSD值均小于2.0%,测定结果与燃灯法一致;选取5份瞬干胶样品按所提出方法各进行5次分析,算得方法的RSD值均小于2.2%,进行了回收试验,方法的回收率为98.1%-103.0%.本法精密度较好,准确可靠,可推广用于其他化工产品中硫的含量测定.

Determination of Sulfur in Petrochemical Products by Oxygen Flask Combustion and Inductively Coupled Plasma-Atomic Emission Spectroscopy

The oxygen flask combustion method is used to treat petrochemical products sample and sulfur in the sample is determined by inductively coupled plasma atomic emission spectroscopy（ICP-AES）.In order to control burning rate and achieve complete combustion,filter paper column and small filter paper are used as supports for pretreatment of diesel fuel sample and instant glue sample,respectively.The sulfurous acid gas（SO2） contained in the combustion gas is dissolved in aqueous solution and determined by ICP-AES. The analytical conditions are optimized. The detection limit is computed to be 0. 019 mg · L-1 through 11 times of blank tests. Precision tests are conducted with 3 diesel oil samples and the relative standard deviations are less than 2.0% , which is consistent with the result obtained by standard test method （lamp method）. Five instant glue samples are also determined and the relative standard deviations are less than 2.2%. Recovery test is conducted and the recovery rate is in the range of 98.1% -103.0%. The method turns out to be simple and precise, which thus may be suitable for the determination of sulfur in other chemical products.