Oxidation-free thiourea leaching of gold uthig sulphur dioxide Ikromjon Boboev, Abubakr Pirov, Rahim Saidzoda, Turaboi Turaev and Dilbar Khakimova BIO Web Conf., 130 (2024) 06007 Published online: 09 October 2024 DOI: 10.1051/bioconf/202413006007