A method is described for the dissolution of molybdenum and rhenium values from a sulfide-type source by pulverizing the source in an aqueous salt solution and electrooxidizing it in an electrolytic cell. Thus, a low-grade molybdenite ore containing about 0.2 Wt pct molybdenum sulfide, minor amounts of copper sulfide, iron sulfide, and sulfur and major amounts of quartz and potassium feldspar is pulverized and slurried with an aqueous solution containing about 10 wt pct sodium chloride. The ore is -35 U.S. standard mesh, with about 65 pct -200 mesh. The slurry is about 10 wt pct pulverized ore. During electrooxidation the slurry is circulated by pumps through the bipolar (graphite) electrodes of the cell and an adjacent stirred surge tank, under the following conditions: current density 0.5 Amp/sq in, ph 5.5-6.5, Slurry temperature 30 deg to 60 deg c, average residence time in the cell 3.5 H. Energy consumption is 25 kw-h per lb of mo extracted. The ph is maintained within the above limits by the addition of sodium carbonate, at a rate of about 5 lb per lb of mo dissolved. Under these conditions, at least 95 pct of the molybdenum sulfide values in the ore are dissolved as sodium molybdate. Rhenium values present also are dissolved as sodium perrhenate. Treated slurry is sent to thickeners and filters to recover the mo-re-containing solution, from which the metals may be recovered by ion exchange or liquid- liquid extraction methods.
U.S. Pat. 3,849,265, Nov. 19, 1974, Chem. Abstr. Not Found