A Novel Trace Elemental Analysis of PotassiumPhosphates

by Joshua Rohman

Institution: University of Cincinnati
Year: 2016
Keywords: Analytical Chemistry; potassium phosphate; ICP-OES; aqua regia; heavy metals
Posted: 02/05/2017
Record ID: 2107459
Full text PDF: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1459243950


In the chemical manufacturing industry, it is critical to have an understanding of not only the major components in the product of interest but also the contaminants or trace components. Potassium phosphates are common to the food and industrial markets, so trace metals are of particular concern in order to protect people as well as processes and equipment from their effects. This can be a particularly difficult task due to the samples having a high dissolved solids content which can cause issues with ICP analyses. In this study, a method is developed to digest anhydrous tetrapotassium pyrophosphate and analyze for trace metals by inductively coupled plasma optical emission spectrometry (ICP-OES). The analytes of interest were As, Cr, Fe, Mn, Ni, Pb, and Zn. Reproducibility was performed; however, spike recovery proved to be a better measure of success due to the majority of the analytes being near or below the method detection limit. The recoveries for all analytes ranged from 96.9-102.4%. Although the recovery was successful, the reproducibility of the analytes above the method detection limit had relative standard deviations mostly greater than 10%, which could be a sign that the solid sample was not homogenous since prior studies with liquid tetrapotassium pyrophosphate had relative standard deviations below 5% Advisors/Committee Members: Heineman, William| (Committee Co-Chair), Landero Figueroa|, Julio (Committee Co-Chair).