The Selective Recovery of Zinc With New Thiophosphinic Acids

Solvent extraction of scandium(III), yttrium(III), lanthanum(III) and gadolinium(III) using Cyanex 302 in heptane from hydrochloric acid solutions

“…It has been reported that this reagent was significantly more resistant toward decomposition by hydrolysis than their phosphoro analogs [6]. In earlier works, the extraction of Sc(III), Zr(IV), Th(IV), Fe(III) and Lu(III) with Cyanex 302 and bis(2,4,4-trimethylpentyl)-dithiophosphinic acid (Cyanex 301) from sulfuric acid media has been investigated and showed favorable performance on the extraction of these metal ions, especially, for Sc(III) [7].…”

Determination of the Degradation Compounds Formed by the Oxidation of Thiophosphinic Acids and Phosphine Sulfides with Nitric Acid

“…In this sense, these thiophosphinic acids are known to be more stable towards hydrolysis. [1][2][3][4] However, it has been reported that contact with nitric acid concentrations greater than 2 M causes degradation of the reagents. 4 This oxidation process complicates the study of the extraction of metal ions from nitric acid media because, on the one hand, there is a less amount of the starting reagent available and, on the other, the metal ions can be extracted by the oxidized species rather than by the species of interest.…”

“…Cyanex 301 ® also has a large amount of tris(2,4,4-trimethylpentyl)phosphine sulfide (R3PS). 1,2 In the present study, FT-IR and GC-MS techniques were applied, because the IR spectroscopic study gives a better understanding of the degradation process and GC-MS allows an exact determination of the decomposition products formed by the oxidation of these compounds with 5 M HNO3. To our knowledge, no previous GC-MS study of the degradation compounds has been undertaken.…”

Interfacial behavior of Cyanex 302 and kinetics of lanthanum extraction

“…Studies demonstrate that it has several advantages for rare earth extraction, including stable composition, higher pK a value (5.63), higher resistance towards decomposition by hydrolysis than other phosphorus analogues [4], stronger extraction ability than Cyanex 272, better selectivity than Cyanex 301 [5], and, especially, high average separation factors for heavy rare earths (β z+1/z Gd-Lu = 3.44) [6]. All of these characteristics demonstrate that Cyanex 302 would be a better extractant for extracting and separating rare earth elements [5].…”