Preparation of Li2PtO3 and its dissolution properties in hydrochloric acid

A double oxide containing Pt and Li, Li2PtO3, was prepared to search for an environment-friendly route to dissolve Pt in hydrochloric acid (HCl). Li2PtO3 powder was obtained by calcination of a mixture of Pt black and Li2CO3 powder at 600, 700 and 800 degrees C. The resulting Li2PtO3 powder was soluble in HCl which has no oxidizing power at ambient temperatures. The Pt solubility of Li2PtO3 obtained at 600 degrees C increased from 39.2 to 99.9% as the temperature of 12 M HCl increased from 40 to 80 degrees C. From ultraviolet visible absorption spectra, it was found that, a complex ion [PtCl6](2) formed as a result of a reaction of Li2PtO3 with HCl. The dissolution process by way of this compound is expected to benefit the establishment of environment-friendly recovery process of Pt. (C)2013 The Ceramic Society of Japan. All rights reserved.