SORPTION AND ION-EXCHANGE PROCESSES Keto Sulfides Derived from tert-Dodecyl Mercaptan and Their Extractive Power with Respect to Palladium(II) and Gold(III)

Keto sulfide concentrates were prepared by alkylthiomethylation of propanone, butanone, and acetophenone with technical-grade tert-dodecyl mercaptan and other sufur-containing substances, and their extractive power with respect to palladium(II) and gold(III) from hydrochloric acid solutions (chloroform as diluent) was studied. DOI: 10.1134/S1070427206110115 Polyfunctional sulfides and petroleum sulfides and sulfoxides are promising extractants for recovery and separation of a number of radioactive, rare, trace, and nonferrous metals (1). -Keto sulfides (2) prepared by alkylthiomethylation (ATM) of ketones with mer- captans (3) are accessible extractants., A method for the synthesis of -keto sulfide concentrates based on natural mercaptan mixtures with prevalent content of C 1 C 6 carbon chains was developed recently (4). To obtain high-molecular-weight keto sulfides by ATM of propanone, technical-grade tert-dodecyl mercaptan was used as a sulfur-containing component (5) (Sala- vatnefteorgsintez Open Joint-Stock Company). In this study, -keto sulfide (hereinafter is omitted for brevity) concentrates were prepared by ATM of propanone, butanone, and acetophenone with a tech- nical mixture of C 12 C 18 mercaptans (TM), and the extractive power of these concentrates with respect to palladium(II) and gold(III) recovered from hydrochlor- ic acid solutions was examined. Industrial mixtures of isomeric C 12 C 18 mercap- tans were used as sulfur-containing reagents. TM-1 (M = 190) is a mixture of C 12 H 25 SH tertiary isomers (96 97%) and C 12 H 24 tert-isoolephins (3 4%). TM-2 (M = 330), along with C 12 H 25 SH tertiary isomers (8%) and C 12 H 24 tert-isoolephins (8%), contains high-molecular-weight mercaptans, sulfides, and di- sulfides (25.0, 26.3, and 8.6%, respectively) and uni- dentified compounds (about 24%) (6).