Abstract: Methods for treating spent reactive soap lubricant baths employed in a cold forming process for metal treatment are described. One method involves treatment of the spent solution with acid to form stearic acid, collection of the stearic acid, and reaction of the stearic acid with a metal salt to form metal stearates. This method is preferably used to prepare sodium stearate. An alternative method involves treatment of a basic (i.e., pH greater than 7 or preferably greater than 10) spent reactive soap lubricant bath with certain metallic stearates, including aluminum stearate, zinc stearate, aluminum stearate, zinc stearate, barium stearate, lithium stearate, and calcium stearate. The metal stearates can be used in conventional lubricant formulations used in the metal forming or metal working industry. Sodium stearate recovered by the present invention is of sufficient purity that it can be reused in reactive soap lubricant baths.

Abstract: A method for treating the phosphate sludge waste from phosphate conversion baths used in the metal forming and metal working industry is described whereby the phosphate sludge is completely converted into a lubricant additive which can be used in lubricant formulations for the metal forming and metal working industry as well as general purpose lubricants. By operation of this process, waste treatment and waste disposal problems associated with the phosphate sludge are essentially eliminated. Various dry-soap lubricant formulations, warm forming lubricant formulations, non-reactive lubricant formulations, and metal precoat formulations containing the recovered or recycled phosphate sludge additive are described. The lime normally contained in many of these lubricant formulations can be significantly reduced or essentially eliminated by using the recovered phosphate sludge additive of this invention, thereby resulting in improved lubricant formulations.