Recovery of nickel and cobalt from laterites by sonic assisted sulfatation

Abstract

There is thus provided a method allowing the recovery of metallic values from laterites by the action of rather diluted sulfuric acid on nickel and cobalt-bearing laterites, at atmospheric pressure and near ambient temperature, assisted by ultrasonic treatment. With an acid concentration in the range for example between about 25 and about 50 weight % of sulfuric acid, under atmospheric pressure, sonication, extracting metallic values from the slurried laterites is thus achieved at room temperature.

We claim: 
     
         1 . A method for recovering metallic values from laterites, comprising:
 slurrying the laterites in sulfuric acid;   submitting the slurry to sonication; and   filtering the slurry.   
     
     
         2 . The method of  claim 1 , comprising slurrying the laterites in a sulfuric acid solution of a concentration in a range between 10 and 95 weight % of sulfuric acid. 
     
     
         3 . The method of  claim 1 , comprising slurrying the laterites in a sulfuric acid solution of a concentration in a range between 25 and 50 weight % of sulfuric acid. 
     
     
         4 . The method of  claim 1 , comprising slurrying the laterites in a sulfuric acid solution of a concentration in a range between 10 and 40 weight % of sulfuric acid. 
     
     
         5 . The method of  claim 1 , conducted at atmospheric pressure near ambient temperature. 
     
     
         6 . The method of  claim 1 , where said sonication is done at a frequency comprised in a range between 10 and 50 kHz. 
     
     
         7 . The method of  claim 1 , wherein said sonication is done at a frequency comprised in a range between 20 and 30 kHz. 
     
     
         8 . The method of  claim 1 , wherein the metallic values comprise at least one of: nickel, cobalt, iron and magnesium. 
     
     
         9 . The method of  claim 1 , wherein the metallic values comprise nickel and cobalt. 
     
     
         10 . A method for recovering nickel and cobalt from laterites, comprising leaching the nickel and cobalt from the laterites with sulfuric acid under sonication. 
     
     
         11 . The method of  claim 10 , comprising using sulfuric acid diluted to 10 to 40% in weight. 
     
     
         12 . The method of  claim 10 , wherein the laterites have a magnesium content up to 20% in weight of said laterite. 
     
     
         13 . The method of  claim 10 , conducted at atmospheric pressure and room temperature.