The extraction of palladium(Ⅱ) from acidic media with
cyclic sulfoxide deriva-
tive-α-octyl-tetrahydrothiophene-Ⅰ-oxide
(OTMSO) was investigated. The extraction efficiency of palla-
dium(Ⅱ) with OTMSO is 97.1% at 0.3mol·L~(-1) OTMSO. The plots of the extraction efficiency for palla-
dium(Ⅲ) appear to lie on a convex curve having a minimum of extraction efficiency at 1-2 mol·L~(-1) HCl. The
extraction reaction of palladium(Ⅱ) with OTMSO is endothermic, and ΔH_(OTMSO)~=12.2kJ·mol~(-1). The coor-
dination number was studied with slope method. The result indicates that coordination number is 2. FT-IR
spectra were used to analyze the structure of complex and
coordinated atom in complex. Pd is coordinated with
both oxygen and sulfur atom in S=O group in OTMSO. The situation and intensity of peaks contributed by
complex prepared from various acidity were different. The recovery of palladium(Ⅱ) with OTMSO from scrap
containing palladium was discussed. After silver and bismuth were removed, the feed solution was extracted
three times by 40% (volume fraction) OTMSO-kerosene. The loaded organic phase was scrubbed three times,
and stripped three times by 2 mol·L~(-1) NH_3·H_2O solution. The total recovery of palladium was 99.8%, and the