Solvent Extraction Systems. I. As(III) and Ge(IV) in Hydrochloric Acid and As(III) in Hydriodic Acid with Several Solvents¹

Abstract

The extraction of As(III) and Ge(IV) from hydrochloric acid solutions by several solvents has been measured. The distribution ratios generally increase in a regular manner as the acid concentration is varied from 2 to 12 F. Differences in extractive power between the solvents carbon tetrachloride, chloroform, bis-(2-chloroethyl) ether and benzene are relatively small. Isopropyl ether shows a maximum in extraction between 7 and 8 F hydrochloric acid for As(III) accompanied by a sharp rise in the solubility of ether in the acid phase as has been observed in the extraction of other elements with this ether.As(III) in hydriodic acid, shows a similar maximum with the solvents used but without the increased phase miscibility.This maximum appears to be related to a change in the nature of the aqueous phase species since the maximum corresponds to a minimum in the solubility of Asli in hydriodic acid.

Fluoride Complexes of Germanium (Iv) in Aqueous Solution

“…(11) have reported small changes in relative volumes on equilibrating equal volumes of concentrated HCl solutions and CC14; however, under the present conditions the voluines of the two phases were found to be unchanged within O.5Y0 provided that clean separations were ensured.…”

Separation and purification of no-carrier-added arsenic from bulk amounts of germanium for use in radiopharmaceutical labelling

“…Separation of As(III) from antimony and bismuth was achieved in 8 M HCl and extraction into benzene [14]. A systematic study on separation of As(III) and Ge(IV) in HCl and HI systems by liquid-liquid extraction into several solvents was carried out by Brink et al [15]. An easy separation of arsenic from germanium was achieved by solvent extraction of arsenic from sulphuric acid solutions after addition of KI into toluene [16,17].…”

Solvent Extraction of Inorganic Species.

“…The distribution of neutral covalent molecules like ruthenium tetroxide (251), iodine (14) or mercury halides (239) between aqueous solutions and inert solvents such as hydrocarbons constitutes one class of behavior, i.e., physical distribution based on relative solubilities. Some compounds, like germanium and arsenic chlorides (45), show this kind of behavior, in addition to extracting as halo-acids.…”

“…Germanium reaches D values of the order of 1000, and arsenic of the order of 100. The species extracted seem to be AsC13 and GeCl4 (45,97,348). Arsenic tribromide (43) and pentabromide (393) are extracted from hydrobromic acid, and both Asl3 (45) and Sbl3 (325) from hydriodic acid.…”

“…The species extracted seem to be AsC13 and GeCl4 (45,97,348). Arsenic tribromide (43) and pentabromide (393) are extracted from hydrobromic acid, and both Asl3 (45) and Sbl3 (325) from hydriodic acid. At higher concentrations of chloride, anionic, non-extractable species are formed, and the distribution coefficients show a maximum around 11 M hydrochloric acid.…”