Abstract
Spectrochemical analysis of solutions has conventionally required drying or ashing the sample to convert it to a solid form. New procedures that continuously feed fresh solution directly into the excitation zone are free of many variables associated with the analysis of dried salts and ashes. Solid materials can usually be put into solution and analyzed with comparative ease. The often-difficult problem of preparing and verifying standards is particularly simplified. Most convenient of these procedures is the use of the rotating electrode. Sensitivity and precision with the rotating electrode are usually excellent. In oil solution, 2 ppm of phosphorus, 0.2 ppm of vanadium, and 0.05 ppm of silver can be detected. In routine analysis of additives in lubricating oils, precision is 2 to 3% of the amount present of each element being determined. Comparable precision applies to the analysis of catalysts, steels, and other solids in solution.