Inspection of a Type 3U7 stainless steel evaporator tube bundle, after eleven months of plant service in concentrating aluminum nitrate, revealed grain boundary and end grain attack which would greatly limit its useful life. This bundle was replaced with one constructed of titanium. Test coupons removed from tanks in which high activity wastes were stored indicated essentially no corrosion after four years in aluminum nitrate waste, and less than 0.2 miles per year corrosion after 2.5 years in zirconium process waste solution. Dilute nitric acid con¬taining mercuric and mercurous nitrates was found to be a useful scrubbing agent for removing iodine from barium-1^0 process off-gas.nIn studies of process methods for aluminum fuel recovery, the addition of gelatin was found to reduce emulsion formation significantly in laboratory tests with silicon-bearing TBP process feed solutions. Dilute hydrofluoric acid and sodium tartrate solution appeared to be more effective than sodium carbonate in reducing the gamma activity of hydrocarbon diluent used to wash uranium product solution. Studies of processing in the acid-deficient region indicated that mercury pre-cipitation and uranium occlusion might limit satisfactory operation to an intermediately basic composition and only moderately greater aluminum concentration than is possible under acid conditions.
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