CONTINUOUS SPECTROGRAPHIC ANALYSIS OF VANADOUS AND VANADIC IONS

VANADOUS FORMATE IS USED IN THE LOMI PROCESS FOR CHEMICAL DECONTAMINATION OF NUCLEAR POWER PLANTS TO REDUCE THE EXPOSURE TO RADIATION BY PLANT PERSONNEL. IN THIS PROCESS, VANADOUS FORMATE IS USED TO PARTIALLY REDUCE IRON AND NICKEL OXIDES THAT CONTAIN RADIOACTIVE MATERIALS, PRIMARILY COBALT OXIDE. THESE METALS ARE THEN CHELATED IN SOLUTION, ABSORBED ON ION EXCHANGE RESINS, SOLIDIFIED AND BURIED. THE LOMI PROCESS HAS BEEN USED FOR ABOUT EIGHT YEARS AND AS YET THERE IS NO RELIABLE METHOD TO DETERMINE THE CONCENTRATION OF THE ACTIVE INGREDIENT, THE VANADOUS (+2) ION. THE PRESENT METHOD OF PROCESS CONTROL CONSISTS OF MAKING MANY ANALYSES OF IRON AND NICKEL IN SOLUTION AND WHEN THESE VALUES STOP INCREASING THE DECONTAMINATION IS TERMINATED. IF AN ON-LINE ANALYSIS FOR THE VANADOUS ION WERE USED, IT WOULD BE POSSIBLE TO DETERMINE WHETHER ALL THE METAL OXIDES IN THE SYSTEM HAD BEEN REMOVED OR THE VANADOUS ION MERELY SPENT. AN ON-LINE ANALYSIS COULD MAKE THIS DETERMINATION AND THIS COULD LEAD TO MORE EFFECTIVE DECONTAMINATIONS. IT IS PROPOSED THAT INFARED OR ULTRAVIOLET-VISIBLE ANALYSIS USING CYLINDRICAL INTERNAL REFLECTANCE SPECTROSCOPY BE INVESTIGATED.