초록 ▼

From roasted products of used catalysts from hydrotreatment desulfurization of petroleum, valuable molybdenum, vanadium, cobalt and nickel are recovered easily and a high percent recovery by means of a combination of simple chemical procedures and also inexpensive chemicals. The recovered metal comp

From roasted products of used catalysts from hydrotreatment desulfurization of petroleum, valuable molybdenum, vanadium, cobalt and nickel are recovered easily and a high percent recovery by means of a combination of simple chemical procedures and also inexpensive chemicals. The recovered metal components can be reused for preparing new catalysts and the like.

대표청구항 ▼

In a process for recovering molybdenum and vanadium from products obtained by oxidative roasting, at a temperature of from about 600°C. to about 950°C., of used catalysts from the hydrotreatment desulfurization of petroleum, the improvement which comprises: (a) subjecting said roasted products to ho

In a process for recovering molybdenum and vanadium from products obtained by oxidative roasting, at a temperature of from about 600°C. to about 950°C., of used catalysts from the hydrotreatment desulfurization of petroleum, the improvement which comprises: (a) subjecting said roasted products to hot water alkaline leaching at a temperature of from about 50°C. to about 100°C. in the presence of a caustic alkali, the amount of the free caustic alkali in the leaching liquid being adjusted to a level of from about 10% to about 30% by weight based on the weight of said leaching liquid; (b) separating the resulting aqueous leaching solution containing substantially all of the molybdenum and vanadium components from solids at a temperature of from about 50°C. to about 80°C. so as not to result in substantial deposition of the vanadium and molybdenum components; (c) cooling the resulting aqueous leaching solution from step (b) to a temperature of from about 0°C. to about 40°C. to precipitate and separate the vanadium component therefrom; (d) recycling the mother liquor resulting from said step (c) and containing mainly the molybdenum component to the hot water alkaline leAching in said step (a) to effect the hot water alkaline leaching of other roasted products while maintaining the alkali condition of said caustic alkali; (e) repeating the recycled leaching and separation under the condition that the molybdenum content accumulated in the mother liquor by said repeated leaching does not exceed about 7% by weight based on said mother liquor. The process according to claim 1, wherein in said step (e) mother liquor is removed.