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The dissolution rates of U308 powders in nitric acid have been investigated in the temperature range 30-95 °C and the acid concentration range 0.1-10 N under atmospheric pressure in order to obtain the basic design data for the dissolution process of voloxidized spent LWR fuel. The dissolution rate was strongly affected by stirring speeds. The highest dissolution rate was obtained in an unstirred run. Above 500 rpm almost identical rate curves were obtained. The rate data obtained at the constant stirring speed of 500 rpm showed that the dissolution proceeded through two stages. The dissolution rate constant during the second stage varied with the 0.8-1.7 power of acid concentration below 6 N HNOa in the temperature range 30-95 °C. The activation energies of 13.9-19.2 kcal/mol were obtained in the acid concentration range 1-4 N HN03 during the second stage. The simulated fission products contained in U308 powder had little depressing action on the dissolution at 2 N HN03.

Radiation damage to 30;.·,:; TBP/kerosene was investigated to determine changes in the extraction behavior of uranium and thorium with the solvent irradiated up to 10 9 R in nitrate system and similarly in the stripping behavior with 0.01 N nitric acid.The effect on uranium and thorium was discernible only with irradiations reaching 109 R.Changes in the behavior of fission products present in company with uranium or thorium were found to be the similar to the case where they existed free of uranium or thorium, At irradiations below 10 7 R, uranium and thorium manifested loading efFect, but it disappeared when irradiation reached 10 8 R.Calculation of one stage decontamination factors of fission products from uranium and thorium confirmed deterioration of the power of separation with irradiation, and the degree of deterioration was determined quantitatively. The decontamination factor for 95 Nb was decreased to l/2,000 by irradiation to lOB R, while the same dosage of irradiation had little effect for t06Ru-'o•Rh.Physical properties such as density, viscosity, emulsification tendency and phase separation time were also observed to be effected by irradiation to lOB R.

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2090 74 26 4 610 43 57of 2H2:1C0. Using an oil yield of 3 barrels per ton of coal, the synthesis gas (0.75H2:1CO) consumption is calculated to be 4000 scf per barrel of oil. In comparison, based on the similar data for the hydrogen run at 450 °C and 15 min (Table V), the hydrogen consumption would be 4700 scf per barrel of oil when the feed gas is hydrogen. It should be noted, however, that the consumption of synthesis gas depends a great deal on the H2/CO ratio, the amount of water, residence time, temperature, and other variables affecting the water-gas shift reaction. Thus, depending on the use of off-gas, one can optimize the consumption of hydrogen and carbon monoxide accordingly.The use of synthesis gas as the feed gas may be applied to Synthoil, -Coal, Consol, and other catalytic hydrogenation processes. The advantages are obvious: (1) the high cost of hydrogen production is saved, and the thermal efficiency increased;(2) the synthesis gas usage can be optimized, and the supply can be obtained at less cost than hydrogen from the gasification of the char produced in the process; and (3) the off-gas, after scrubbing out carbon dioxide and hydrogen sulfide, is a low-Btu gas. With the H2/CO ratio of about 3, it is suitable for use in methane production or methanol synthesis. If one recycles the gas, only a small bleed stream is necessary to keep CH4 level down. The bleed gas could be burned for process heat. ConclusionsHigh sulfur bituminous coal can be liquefied and desulfurized by hydrotreating with synthesis gas at 3000 psi and 425-450 °C in the presence of cobalt molybdate-sodium carbonate catalyst, steam, and recycle oil. The sulfur content and the viscosity of the oil product both decrease with the amount of hydrogen consumed whether synthesis gas or hydrogen is used as the reactant gas, but less total hydrogen is required for the same oil product quality when synthesis gas is used. The synthesis gas consumption can be conveniently optimized, the cost of hydrogen production is saved, and the off-gas can be optionally burned as a low-Btu gas or utilized for methane production or methanol synthesis.Literature Cited