Abstract A process for recovering nickel from primary rock materials with a very low nickel content characterized by massive occurrences therein of a relatively uniform and very low grade of nickel in the form of sulphides, oxides, alloys and silicates, very low sulphur and low copper and iron values, low sulphur to nickel ratios and the absence or negligible occurrences of pyrrhotite. The process comprises the grinding of the rock materials to fine particles, adding sodium chloride or other alkali metal chlorides and coal, by itself or in combination with other carbonaceous reducing agents, roasting the resulting mixture in a near neutral atmosphere at temperatures from 800* to 1100*C. for a sufficient time to effect conversion of a substantial amount of the nickel content to nickel in metallic, alloy or oxide forms, cooling the resulting mixture under non-atmospheric conditions to a nonreacting temperature and removing the magnetic fraction from the roasted mixture by magnetic separation procedures.
Inventors
👤 I Iwasaki
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-06 15:23
CPC Classifications
C; C22; C22B; C22B23/00; C22B23/02; C22B23/021
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
14 words
A process according to claim 1 wherein the alkali metal chloride is sodium chloride.
Claim 2
Dependent Claim
22 words
The process according to claim 1 wherein the amount of alkali metal chloride is between about 3/4 and 5 percent by weight.
Claim 3
Dependent Claim
23 words
The process according to claim 1 wherein the amount of solid carbonaceous reducing agent is between about 0.5 and 6 percent by weight.
Claim 4
Dependent Claim
19 words
A process according to claim 1 wherein the roasting time is between about 20 minutes and 1 1/2 hours.
Claim 5
Dependent Claim
25 words
The process according to claim 1 wherein the solid carbonaceous reducing agent is coal having a particle size between about -20 mesh to -60 mesh.
Claim 6
Dependent Claim
15 words
The process according to claim 1 wherein the primary rock material is an ultramafic ore.
Claim 7
Dependent Claim
13 words
The process according to claim 7 wherein the ultramafic ore is a peridotite.
Claim 8
Dependent Claim
16 words
The process according to claim 1 wherein the primary rock material is a volcanic fragmented rock.
Claim 9
Dependent Claim
47 words
The process according to claim 1 wherein the nickel concentrate obtained after magnetic separation has a nickel content (percent by weight) of not less than about 8 percent, said nickel representing not less than about 75 percent of the original nickel content in the untreated rock material.