Abstract: Provided is a hydrometallurgical process for nickel oxide ore by high pressure acid leach that achieves a high iron oxidation ratio. The carbon grade in ore slurry and the flow rate are measured to determine the amount of carbon to be fed, and then, sulfuric acid is added. The blowing ratio of high pressure air and high pressure oxygen is adjusted so as to attain an oxygen purity of 21% to 60%. While the oxygen purity is maintained, an oxygen blowing amount per weight of carbon contained in the ore slurry and fed in the second step is adjusted to 200 to 600 Nm3, whereby ORP (Ag/AgCl basis) in the leaching treatment is controlled to 400 to 650 mV.

Abstract: Provided is a hydrometallurgical process for nickel oxide ore by high pressure acid leach that achieves a high iron oxidation ratio. The carbon grade in ore slurry and the flow rate are measured to determine the amount of carbon to be fed, and then, sulfuric acid is added. The blowing ratio of high pressure air and high pressure oxygen is adjusted so as to attain an oxygen purity of 21% to 60%. While the oxygen purity is maintained, an oxygen blowing amount per weight of carbon contained in the ore slurry and fed in the second step is adjusted to 200 to 600 Nm3, whereby ORP (Ag/AgCl basis) in the leaching treatment is controlled to 400 to 650 mV.

Abstract: A method for reducing usage amount of expensive high alkaline neutralizer, and applying efficient neutralization treatment, when applying a neutralization treatment to a barren solution to produce in a treatment step, in which a sulfide compose of nickel and cobalt is produced from a sulfuric acid aqueous solution containing nickel and cobalt, and impurity metals containing at least one or more of iron, magnesium, and manganese. A first neutralization treatment step of applying a neutralization treatment to the barren solution, with a range of pH 5.0 to 6.0 as the end point, by using calcium carbonate slurry, as a first neutralizer; and a second neutralization treatment step of applying a neutralization treatment to a solution produced in the first neutralization treatment step, by using a second neutralizer, to produce sediment containing metal remained in the barren solution and a post-neutralization solution from which a metal ion is removed.

Abstract: A curable resin composition comprising (A) reactive particles prepared by bonding (A1) at least one of oxide particles of an element selected from the group consisting of silicon, aluminum, zirconium, titanium, zinc, germanium, indium, tin, antimony, ruthenium, rhenium, silver, nickel, cupper and cerium, and (A2) an organic compound which comprises a polymerizable unsaturated group, (B) a compound having two or more polymerizable unsaturated groups in the molecule, and optionally (C) a terminal reactive polysiloxane compound having at least one polymerizable group, other than organic compound (A2).