Hydrogen sulfide and mercaptans in hydrocarbons, gas mixtures of hydrocarbons and the like may be scavenged therefrom by being brought into intimate contact with a mercaptan scavenger formulation of quaternary ammonium alkoxide or hydroxide in the presence of a high oxidative state metal such as cobalt, iron, chromium and/or nickel. The high oxidative state metal, being an oxidizer, acts as a catalyst when combined with the quaternary ethoxide or hydroxide for improved mercaptan scavenging performance.