Patent application number | Description | Published |
20080274026 | SELECTIVE PRECIPITATION OF METAL SULFIDES - A method for recovering zinc ions by selective zinc sulfide precipitation from an aqueous solution comprising zinc ions and metal ions of a metal that precipitates as a metal sulfide at a pH lower than a pH at which zinc ions precipitate as a zinc sulfide. | 11-06-2008 |
20090071296 | PROCESS FOR CONTROLLING ACID IN SULFIDE PRESSURE OXIDATION PROCESSES - The present invention is directed to flotation of refractory gold sulfide ores and to pressure oxidized residue neutralization using flotation tailings that have been contacted with an off gas of pressure oxidation. | 03-19-2009 |
20090074608 | PROCESS FOR MERCURY CONTROL DURING PRESSURE OXIDATION - A method for suppressing mercury dissolution during pressure oxidation of precious metal-containing materials in the presence of halogens and halides is provided. Pressure oxidation is performed under controlled oxidative conditions to maintain the mercury predominantly in the solid residue. | 03-19-2009 |
20090158893 | MICROBIAL PRE-TREATMENT OF DOUBLE REFRACTORY GOLD ORES - The present invention is directed to recovery of gold from refractory and double refractory ores using a fungal agent and/or culture media. | 06-25-2009 |
20110165059 | PRODUCTION OF ZINC SULPHATE CONCENTRATES FROM A DILUTE ZINC SULPHATE SOLUTION - In an embodiment, the present invention relates to an apparatus and a process for producing a concentrated form of basic zinc sulphate from a, typically dilute, acidic zinc sulphate-bearing solution. The process embodiment comprises the steps of precipitating the zinc, preferably primarily as basic zinc sulphate, from the acidic zinc sulphate solution, preferably using calcium oxide, in such a way as to promote the formation of separate gypsum crystals and basic zinc sulphate particles, and upgrading the zinc content in the precipitates by separating the basic zinc sulphate from the gypsum using size separation techniques. | 07-07-2011 |
20120183433 | CO-CURRENT AND COUNTER CURRENT RESIN-IN-LEACH IN GOLD LEACHING PROCESSES - A method and system are provided in which a gold and/or silver-collecting resin-in-leach circuit comprises both co-current and counter-current sections. | 07-19-2012 |
20130091990 | METHOD FOR RECOVERING PRECIOUS METALS AND COPPER FROM LEACH SOLUTIONS - The present disclosure is directed to a process for recovering a precious metal from a pregnant leach solution using a resin extractant. The precious metal is eluted from the loaded resin using an eluant comprising trithionate. The barren resin is contacted with a sulfide, bisulfide, and/or polysulfide to convert sorbed trithionate to thiosulfate. The desorbed thiosulfate is contacted with an oxidant and converted to trithionate for eluant recycle. | 04-18-2013 |
20140035207 | Co-Current and Counter Current Resin-In-Leach in Gold Leaching Processes - A method and system are provided in which a gold and/or silver-collecting resin-in-leach circuit comprises both co-current and counter-current sections. | 02-06-2014 |
20140356225 | METHOD FOR PRE-TREATMENT OF GOLD-BEARING OXIDE ORES - The disclosure relates to pre-treatment of precious metal-bearing oxide ores, prior to precious metal leaching by thiosulfate. The process comprises mixing oxide ore in oxygenated water in the presence of a carbon-based material (e.g., activated carbon or other type of carbon). The carbon-based material can be separated from the ore slurry, and, the gold is thereafter leached by a thiosulfate lixiviant. | 12-04-2014 |