摘要
为解决采用电感耦合等离子体原子发射光谱法(ICP-AES)测定车用汽油中铁、锰、铅含量时易出现熄火、点不燃、结果不稳定等问题,优化了稀释剂、稀释比[样品与5mg·L^(-1)钴内标工作溶液(稀释剂为煤油)质量比]和定量方式,提出了题示方法。取5g车用汽油样品,按照稀释比1∶9加入5mg·L^(-1)钴内标工作溶液45g,混合均匀后用有机物进样系统进样,在射频功率1300W、冷却气流量16.0L·min^(-1)、辅助气流量1.1L·min^(-1)、雾化气流量0.4L·min^(-1)下测量238.204,257.610,220.353nm处铁、锰、铅谱线强度,内标法定量。结果显示:3种目标元素的质量分数均在0.20~5.00mg·kg^(-1)内与对应的谱线强度比呈线性关系,检出限(3S/N)为0.04~0.06mg·kg^(-1)。对空白汽油样品进行3个浓度水平的加标回收试验,回收率为93.8%~106%,重复性和再现性试验结果均在重复性限和再现性限以内。方法用于6个实际样品的分析,3种目标元素的检出量和标准方法GB/T 8020-2015(检测铅)、SH/T 0711-2019(检测锰)、SH/T 0712-2002(检测铁)所得结果的相对误差的绝对值均在6.5%以内。
In order to solve the problems of flameout,ignition failure and unstable results in the determination of iron,manganese and lead in motor gasoline by inductively coupled plasma atomic emission spectrometry(ICP-AES),the diluent,dilution ratio[the mass ratio of sample to 5 mg·L^(-1) cobalt internal standard working solution(with kerosene as the diluent)]and quantitative mode were optimized,and the title method was proposed.An aliquot(5g)of motor gasoline sample was mixed with 45g of 5mg·L^(-1) cobalt internal standard working solution at dilution ratio of 1∶9.After mixing evenly,the mixture was introduced by organic matter sampling system.The intensities of iron,manganese and lead at 238.204,257.610,220.353nm were measured at radio frequency power of 1300W,cooling gas flow rate of 16.0L·min^(-1),auxiliary gas flow rate of 1.1L·min^(-1),and atomizing gas flow rate of 0.4 L·min^(-1).The internal standard method was used for quantification.It was shown that linear relationships between values of the mass fractions of the 3target elements and the corresponding spectral line intensity ratio were kept in the range of 0.20-5.00mg·kg^(-1),with detection limits(3S/N)in the range of 0.04-0.06mg·kg^(-1).The spiked recovery test was conducted on blank gasoline samples at the 3concentration levels,giving recoveries ranging from 93.8%to 106%,and results of tests for repeatability and reproducibility were within the repeatability limit and reproducibility limit.The proposed method was applied to the analysis of the 6actual samples,and the relative error absolute values of detection amounts of the 3target elements and results obtained from standard methods of GB/T 8020-2015(detection of lead),SH/T 0711-2019(detection of manganese),and SH/T 0712-2002(detection of iron)were within 6.5%.
作者
李财虎
王伟
赵双宏
王文华
冯莉莉
LI Caihu;WANG Wei;ZHAO Shuanghong;WANG Wenhua;FENG Lili(Ningxia Academy of Metrology&Quality Inspection,Yinchuan 750411,China;National Measurement and Testing Center for Coal Chemical Industry,Yinchuan 750411,China)
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2023年第9期1067-1072,共6页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
基金
宁夏回族自治区科技惠民专项项目(2022CMG03067)。
