Abstract: The present invention relates to use of an amino-containing neutral phosphine extractant of Formula I in extraction and separation of thorium, and a process of extracting and separating thorium using the amino-containing neutral phosphine extractant of Formula I, wherein, R1 and R2 are each independently selected from the group consisting of C1-C12 alkyl, R3 and R4 are each independently selected from the group consisting of C1-16 alkyl and hydrogen, and n is an integer of 1 to 8.

Abstract: The present invention relates to use of an amino-containing neutral phosphine extractant of Formula I in extraction and separation of thorium, and a process of extracting and separating thorium using the amino-containing neutral phosphine extractant of Formula I, wherein, R1 and R2 are each independently selected from the group consisting of C1-C12 alkyl, R3 and R4 are each independently selected from the group consisting of C1-16 alkyl and hydrogen, and n is an integer of 1 to 8.

Abstract: The present invention relates to a process of separating and purifying thorium by solvent extraction, comprising: 1) mixing a thorium enrichment with an inorganic acid to produce a feed; 2) mixing a neutral phosphorus extractant with an organic solvent to obtain an organic phase; 3) extracting from the feed with the organic phase to obtain a loaded organic phase; 4) scrubbing the loaded organic phase with a scrubbing solution and then back-extracting thorium with a stripping solution to obtain a thorium solution; 5) mixing the thorium solution with an oxalate to obtain a precipitate, which is then sintered to obtain thorium oxide. The present process allows to increase the purity of thorium from 80%-99% to 99.99% or more with a yield of more than 98%.