Interaction between lanthanide cuprates and hydrochloric acid

The interaction between lanthanide cuprates Ln2CuO 4-δ (Ln = La-Gd) and hydrochloric acid is investigated. The effects of solution pH, temperature, and the nature of the rare-earth element ion on dissolution is studied. The formal order of the reaction in the acid is the same for all the substances under study and is 0.53 ± 0.05. The effective activation energy for the process is 40 ± 0.5 kJ/mol. A scheme of Ln2CuO4-δ interaction with HCl is proposed. © Pleiades Publishing, Ltd., 2011