Duncan, Trussell, and Walden reported the effect of nonionic surfactants on the Thiobacillus ferrooxidan leaching of chalcopyrite. The tests were conducted in 250-mL Erlenmeyer flasks containing minus 325 mesh chalcopyrite and a modified 9K medium at pH 2.5 and 35° C. The hypothesis tested in adding the surfactants was that the presence of a surfactant … Read more

Previous U.S. Bureau of Mines (USBM) research on the leaching of chalcopyrite with ferric sulfate [Fe2(SO4)3] demonstrates that surfactant additions enhance chalcopyrite (CuFeS2) leaching and that surfactant selection has a significant impact on the initial leaching rate. Additions of chloride ion (Cl-) are also known to enhance chalcopyrite leaching, although a review of the literature … Read more

As part of its mission to reduce the environmental impact of minerals processing, the U.S. Bureau of Mines (USBM) investigated the characterization and treatment of Hg-contaminated wastes from an electrical-parts manufacturing plant. A literature search showed various hydrometallurgical methods for recovering Hg have been investigated on a laboratory scale, but there has never been a … Read more

An estimated 17 million mt of manganese are contained in domestic manganese-bearing silicate resources, yet domestic production is insignificant compared with the quantity of manganese imported yearly into this country for consumption. The projected U.S. consumption of manganese in 1990 was expected to be about 680,400 mt with the majority of total demand being supplied … Read more