Characterization of a 12 M KOH zincate fuel for green energy backup systems using flow injection coupled to inductively coupled plasma optical emission spectrometry

Abstract

For the first time, the overall analysis of a 12 M KOH zincate fuel, which is used in green energy backup systems, is explored using inductively coupled plasma optical emission spectrometry (ICPOES). A quick novel method allowing monitoring of the fuel was developed to avoid time-consuming neutralization/digestion of KOH. By employing various techniques, including flow injection analysis with matrix-matched external calibration, and standard additions of 10-fold diluted fuel, a final procedure was formulated for the measurement of additives (Al, Fe, Mg, In, Si), corrosion products (such as C from CO₃²⁻), and Zn particles filtered from solution, along with verification of K concentration. Furthermore, the effects of exposing the potassium zincate electrolyte fuel to air were assessed, demonstrating how potassium carbonate precipitate formation could affect the elemental concentrations in the fuel over time.