微波等离子体原子发射光谱分析原油中的微量金属元素

研究建立了原油中微量金属元素低成本高通量测定的分析方法。原油样品经HNO₃+H₂O₂密闭压力消解后，直接采用微波等离子体原子发射光谱(MP-AES)测定其中的12种微量金属元素Cu、Fe、Zn、Pb、Ni、K、Mn、Ba、Cr、V、Mg、Al。通过选择待测元素的分析波长，并结合快速线性干扰校正(FLIC)技术校正了光谱干扰，选择Y和Lu为内标元素校正了基体效应，稳定了分析信号。采用标准参考物质NIST-SRM 1084a(润滑油中的磨损元素)评价了分析方法的准确性。结果表明:所有分析元素的线性关系良好(线性相关系数≥0.9995);该方法的检出限(MDL)为0.04~1.15 μg/g，NIST SRM 1084a的测定值与认定值基本一致，验证了所建立的方法准确可靠，使用N₂为等离子体气体的MP-AES显著降低了分析成本。该方法为原油中多种微量金属元素的高通量分析提供了新策略。

Trace Metals Analysis in Crude Oils With Microwave Plasma Atomic Emission Spectroscopy

Determination of trace metals in crude oils was established with a low cost and high-throughput method. Crude oil samples were first digested by the HNO₃ and H₂O₂ mixture in a closed pressurized system, and then 12 elements i.e., Cu, Fe, Zn, Pb, Ni, K, Mn, Ba, Cr, V, Mg, and Al, in the digested solution were further determined with the microwave plasma atomic emission spectroscopy (MP-AES). Spectral interference was corrected by analytical wavelength selection of the analytes, and combined with fast linear interference correction (FLIC) technology. Y and Lu were used as internal standards to correct the matrix effect and stabilize analytical signals. Standard reference material NIST SRM 1084a (wear-metals in lubricating oil) was used to evaluate the accuracy of the analytical method. Experimental results show that the linear relationship of all analytes were excellent (linearly dependent coefficient no less than 0.9995), with detection limit (MDL) of 0.04-1.15μg/g. It was found that the measured value of NIST SRM 1084a is consistent with the certified data. This suggests that the developed method is accurate and reliable, and MP AES using nitrogen as plasma gas can significantly reduce operation cost. Thus, the developed method provides a new strategy for high-throughput analysis of trace metals in crude oils.