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US 4,298,379 AGranted
Production of high purity and high surface area magnesium oxide
AssigneeThe Hanna Mining Company
InventorAdolfo R. Zambrano
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AssigneeThe Hanna Mining Company
InventorAdolfo R. Zambrano
Estimating the term…
Disclosed is a process for refining a magnesium and nickel containing ore, comprising the steps of grinding the ore; preparing a slurry of the ground ore in sulfuric acid containing less than ten percent of water; adding water to the acid-ore slurry in an amount which is effective to initiate a sulfation reaction; allowing the sulfation reaction to continue, utilizing the heat of the sulfation reaction to heat the acid-ore slurry, whereby water-soluble metal sulfates and insoluble residue are formed; leaching the sulfation product with water to extract the water-soluble metal sulfates in solution; separating the metal sulfates solution from the insoluble residue; precipitating from the solution metals other than Mg as hydroxides; separating the solution from the metal hydroxide precipitate; concentrating the solution sufficiently to precipitate CaSO.sub.4 ; separating the concentrated solution from the precipitate; recovering dehydrated MgSO.sub.4 crystals from the concentrated solution; and decomposing the dehydrated MgSO.sub.4 crystals to form MgO of controlled surface area. Additionally disclosed are an autoclave step for reducing iron values in the metal sulfates solution, nickel or ferronickel recovery steps, a sulfuric-acid recycle; refractory MgO production steps, and Mg metal recovery steps.
A process for the preparation of high surface area, high purity MgO from a solution of:
A process for the preparation of high purity, high surface area MgO suitable for producing refractory materials, from a solution of:
A process for refining a magnesium, calcium, iron and nickel containing ore, comprising the steps of:
Dependencies are inferred from the claim text.