The automated determination of alkyl aryl sulfonates in spray‐dried detergents by ultraviolet absorption

Abstract

An automated procedure has been developed for the determination of alkyl aryl sulfonates in spray-dried detergents. It is based upon the ultraviolet absorbance of alkyl aryl sulfonates at 224 m/~. A Technicon Solid Preparative ~ampler is employed to dissolve the sample, dilute it to a fixed volume and remove an aliquot for analysis. The sample aliquots are continuously fed by a Technicon Proportioning Pump to a flow cell in a recording spectrophotometer. All operations, excluding sample weighing, are automatic and analyses can be carried out continuously at the rate of 10 samples per hour. The method has been found to have a coefficient of variation of 3.5%.