Abstract
The distribution ratio of uranium between tri-n-butyl phosphate and water decreased with the addition of water-insoluble carboxylic acids such as benzoic, lauric, oleic and stearic acids at various concentrations of nitric acid. It is suggested that the decrease of uranium distribution ratio may be due to hydrogen bond formation between tri-n-butyl phosphate and carboxylic acid. It was indicated from infrared spectrometry that a strong hydrogen bond is formed between tri-n-butyl phosphate and carboxylic acid. In other cases, water-soluble carboxylic acids such as acetic, adipic and oxalic acids had no effect at all on the distribution ratio of uranium at various concentrations of nitric acid.
