Determining Ash Content and Trace Metal Concentration in Crude Oil Samples to Teach Students Sample Preparation and Instrumental Analysis

Trace metals when present in crude oil or fuels are of economic significance in refining and to the combustion engines that use them. Herein, we develop a laboratory activity that trains students on how to analyze crude oil samples for ash and trace metal content while giving them the opportunity to acquire skills needed as a quality control analyst in the industry. Students were divided into three groups and were trained on sample preparation, standard preparation, and quantificational and operational use of the flame atomic absorption spectrophotometer. Each group after preparing their samples quantified the concentration of Pb, Cu, Ni, Zn, and Mn in crude oil samples. The discussion over the results enabled the students to draw inferences on the sampling methods, and ways to improve precision and accuracy in instrumental analysis.