MANUFACTURE OF DETERGENT ACTIVES

摘要

A method is disclosed for preparing fatty acid isethionate soaps through direct esterification wherein the catalyst is quenched by an alkaline compound at the end of the esterification. Quenching inhibits transesterification between isethionate and later added stearic acids. Transesterification is undesirable impairing lather and bar soap firmness. The traditional stripping of lower molecular weight fatty acids is no longer necessary where low ratios of fatty acids to isethionates are utilised. Alternatively, stripping can be avoided with traditional molar ratios provided water co-distilate fatty acid is not recycled. Finally, it has been shown that zinc catalysed reactions provide optimum yield and low corrosion at pH about 2.0 to 2.5.