美国专利3203786提出从海绵铁渣、竖炉渣或低品位硅酸镍矿石中回收镍和钴的方法。将原料与含硫物料和一种硷金属或一种硷土金属氯化物混合。混合物在有氧存在的条件下于250～600℃下焙烧。焙砂用水、氨或弱酸浸出,以溶解镍和钴。溶液 pH 至少要调至7.0,以便使其他有价金属能与铁一起沉淀。沉淀物用氧化剂处理使铁氧化。用酸性水溶液使镍、钴选择溶解,以生成 pH 至少为4.0的溶液,将这一溶液的 pH 上升至6.0以沉淀镍和钴。 U.S. Patent 3,203,786 teaches a method of recovering nickel and cobalt from sponge iron slag, shaft slag or low grade nickel silicate ore. The feedstock is mixed with the sulfur-containing material and an alkali metal or an alkaline earth metal chloride. The mixture is calcined at 250-600C in the presence of oxygen. Calcite is leached with water, ammonia or weak acid to dissolve nickel and cobalt. The pH of the solution should be adjusted to at least 7.0 so that other valuable metals can precipitate with the iron. The precipitate is oxidized with iron oxide. The nickel and cobalt are selectively dissolved with an acidic aqueous solution to produce a solution having a pH of at least 4.0 and the pH of this solution is raised to 6.0 to precipitate nickel and cobalt.