Determination of metallic elements in catalysts by flame atomic absorption spectrometry following microwave energy-assisted dissolution of samples

Abstract

A method is presented for the determination of Al, Si, Fe, Ti, V, Mo, Ni and Co in catalysts used in different processes in the oil and petrochemical industries. The method is based on the dissolution of samples in a nitric and hydrofluoric acid mixture aided by microwave energy. After dissolution of the samples, the elements of interest are present in a matrix of fluoboric acid (60% v/v), where they are determined by flame atomic absorption spectrometry (FAAS). Interference studies for the FAAS determination of elements based on experimental statistical factorial designs are also presented. Recoveries better than 96% for all elements were obtained with relative standard deviations lower than 5% for major components and lower than 6% for minor components.