RADIOISOTOPE AND RADIATION APPLICATIONS. Quarterly Progress Report

A series of experiments was completed using the process model for studying radiotracer control of iron removal from a nickel-refinery stream. The results of 13 experimental runs indicated that the radiotracer control concept is technically sound. The iron reduction ratios obtained by radioassay agreed well with the iron reduction ratios given by chemical analysis. The radioactivity monitor on the filtrate stream provided a rapid and sensitive indication of changes in process operating conditions. The survey of chemical engineering unit operations as potential intrinsic radiotracer applications was completed. The study of the mechanism of formation of free radicals in polymethacrylates was continued. Particular emphasis was placed on an examination of the effect of structural factors on the efficiency of free-radical site formation. The investigation of the influence of free-radical formation of the hydrocarbon constituent of the ester side chain was continued. In addition, polymer molecular weight was found to influence site concentration. (auth