Abstract: A method of extracting zinc from a sulphidic ore is provided which comprises bioleaching the ore in a heap with acidophilic microorganisms to produce a pregnant leach solution which is recovered from the bottom of the heap. An integrated process which comprises subjecting the pregnant leach solution to neutralization and solvent extraction to produce a concentrated zinc solution is also provided. Zinc may be recovered from the concentrated solution by means of electrowinning, either in the absence or presence of manganese. Alternatively zinc may be recovered in the form of a zinc compound.

Abstract: A single step method and apparatus for the production of expanded metal mesh from deformable metal strip such as lead or lead-alloy strip for use in lead-acid battery manufacture. The apparatus comprises a pair of opposed rolls each having a plurality of spaced discs having opposite side walls and circumferential, equally spaced, convexly shaped tool surfaces alternating with substantially flat surfaces, said discs having radial notches formed in the opposite sidewalls of alternate circumferential flat surfaces, whereby peripheral surfaces of opposing rolls are adapted to interact on deformable strip passing therebetween to concurrently slit and form convex wire segments and alternate nodes in said strip by intermeshing of said shaped tool surfaces.

Abstract: A process and an alloy for galvanizing non-reactive steel and mixed or moderately reactive steel for providing a decorative spangle to the galvanized coating. The alloy contains 0.1 to less than 0.8 wt % tin, 0.05 to 0.2 wt % bismuth, 0.001 to 0.008 wt % aluminum, and optionally 0 to 0.1 wt % nickel, the balance zinc of commercial purity.

Abstract: A method of extracting zinc from a sulphidic ore is provided which comprises bioleaching the ore in a heap with acidophilic microorganisms to produce a pregnant leach solution which is recovered from the bottom of the heap. An integrated process which comprises subjecting the pregnant leach solution to neutralization and solvent extraction to produce a concentrated zinc solution is also provided. Zinc may be recovered from the concentrated solution by means of electrowinning, either in the absence or presence of manganese. Alternatively zinc may be recovered in the form of a zinc compound.