A method for preparing an emulsion cleaning composition that is resistant to separation upon exposure to depressed and elevated temperatures and which exhibits a persistent peroxide content comprises preparing an organic portion and an oxidant portion and then combining the organic portion and the oxidant portion under mixing to make the emulsion. The organic portion comprises an organic solvent, and emulsifier and a cleaner surfactant. The oxidant portion comprises an oxidizing compound activator and a peroxide generator. The emulsion cleaning composition is useful for removing petroleum distillate residue from metal surfaces such as refinery surfaces.