Diphenylglyoxime is primarily used as a reagent in analytical chemistry for the detection and quantification of nickel and palladium ions. It forms highly colored complexes with these metals, making it a valuable tool in qualitative and quantitative analysis. In metallurgy, it assists in the separation and purification of nickel from ores and other metal mixtures. Additionally, it is employed in organic synthesis as a chelating agent to stabilize metal ions during chemical reactions. Its ability to selectively bind with specific metals also makes it useful in environmental testing to monitor metal contamination in water and soil samples.