Studies on the effect of structure on third phase formation in the extraction of thorium by N,N-dialkyl amides

The influence of the molecular structure of the amides on the third phase formation in the extraction of thorium was investigated. Four amides namely DHOA (Dihexyl octanamide), DOHA (Di n-octyl hexanamide). DBDDA (Dibutyl dodecanamide) and DHHA (Dihexyl hexanamide) were synthesised and third phase formation studies were performed using 1M solutions of these amides in dodecane at 303 K. The Limiting Organic Concentration (LOC) of thorium was determined as a function of nitric acid concentration. The LOC values were found to be higher in the case of DOHA as compared to those of DHOA, DBDDA and DHHA which may be due to the difference in the carbon chain length. (author)