Selective Recognition of Precious Metals From Automotive Catalyst Residue by Thiacalix(6)arene Derivative

A new derivative matter acetylthiomethylthiacalix(6)arene (TC6A-CH2SCOCH3) has been syn- thesized by modified the upper rims of p-tert-butylthiacalix(6)arene (TC6A) in anhydrous DMF. The metal extraction properties of TC6A-CH2SCOCH3 from automotive catalyst residue solution containing plati- num-group metal (PGM) cations have been investigated. It shows that the highest extractability for Pd and second highest one for Zr are ca. 86.2% (in pH 1.5 PGM solution) and 57.3% (in pH 4.0 PGM solution) re-