caa a22 4500 475815726 CHVBK 20180406123809.0 cr unu---uuuuu 170329e20001001xx s 000 0 eng 10.1023/A:1004087209541 doi (NATIONALLICENCE)springer-10.1023/A:1004087209541 Effect of chromate additive on the kinetics and mechanism of skeletal copper formation [Elektronische Daten] [A.J. Smith, L. Ma, T. Tran, M.S. Wainwright] The addition of chromate to the leach liquor for the preparation of skeletal copper increases and stabilizes the copper surface area and slows the leaching rate. The kinetics have been studied using a rotating disc electrode (RDE) at 269-293 K in 2-8 M NaOH and 0-0.1 M Na2CrO4. The rate of leaching was found to be constant with time, with an activation energy of 74 ± 7 kJ mol−1. By monitoring the kinetics and free (mixed) corrosion potential, it was possible to elucidate the mechanistic effect of chromate causing the increased surface area. Chromate was found to deposit on the copper surface as chromium(III) oxide, hindering the leaching reaction as well as the dissolution/redeposition of copper, the main mechanism of structural formation/rearrangement for skeletal copper. This blocking of the surface resulted in a finer structure, with a corresponding larger surface area. It also stabilised the surface area by minimizing the rearrangement. The effect of chromate was found to reach a limit at around 0.03 M Na2CrO4. Kluwer Academic Publishers, 2000 chromium dopant nationallicence de-alloying nationallicence Raney® copper catalysts nationallicence selective dissolution nationallicence structure nationallicence Smith A.J. School of Chemical Engineering & Industrial Chemistry, University of New South Wales, 2052, Sydney, Australia aut Ma L. School of Chemical Engineering & Industrial Chemistry, University of New South Wales, 2052, Sydney, Australia aut Tran T. School of Chemical Engineering & Industrial Chemistry, University of New South Wales, 2052, Sydney, Australia aut Wainwright M.S. School of Chemical Engineering & Industrial Chemistry, University of New South Wales, 2052, Sydney, Australia aut Journal of Applied Electrochemistry Kluwer Academic Publishers 30/10(2000-10-01), 1097-1102 0021-891X 30:10<1097 2000 30 10800 https://doi.org/10.1023/A:1004087209541 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1004087209541 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Smith A.J. School of Chemical Engineering & Industrial Chemistry, University of New South Wales, 2052, Sydney, Australia aut NATIONALLICENCE 700 1- Ma L. School of Chemical Engineering & Industrial Chemistry, University of New South Wales, 2052, Sydney, Australia aut NATIONALLICENCE 700 1- Tran T. School of Chemical Engineering & Industrial Chemistry, University of New South Wales, 2052, Sydney, Australia aut NATIONALLICENCE 700 1- Wainwright M.S. School of Chemical Engineering & Industrial Chemistry, University of New South Wales, 2052, Sydney, Australia aut NATIONALLICENCE 773 0- Journal of Applied Electrochemistry Kluwer Academic Publishers 30/10(2000-10-01), 1097-1102 0021-891X 30:10<1097 2000 30 10800 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer