Table 4.
Results of dissolution of different nickel fractions (N°=3).
| Nickel Species | Solution | Treatment | Aspect | Ni expected (mg) | Ni determined (mg) | % extracted |
|---|---|---|---|---|---|---|
| NiSO 4 | ammonium citrate (Sol A) | 10mL, 37°C, 60min | clear | 1.6 | 1.70±0.1 | 102% |
| H2O2 citrate: ammonium citrate (Sol B) | 10mL, ΔT, 60min | clear | 2.3 | 2.1±0.2 | 91% | |
| solution methanol:Bromine (solution C) | 10mL, ΔT, 2h | clear | 1.8 | 1.6±0.1 | 89% | |
| Solution HCl: HNO3 1:1 (Sol D) | 4mL, 70°C, 30min | clear | 2.6 | 2.7±0.3 | 103% | |
|
| ||||||
| Ni 3 S 2 | ammonium citrate (Sol A) | 10mL, 37°C, 60min | residue | 10.8 | 0.31±0.1 | 0.03% |
| H2O2 citrate: ammonium citrate (Sol B) | 10mL, ΔT, 60min | clear | 7.6 | 7.4±1.1 | 96% | |
| solution methanol: Bromine (solution C) | 10mL, ΔT, 2h | clear | 8.0 | 8.3±0.8 | 103% | |
| Solution HCl: HNO3 1:1 (Sol D) | 4mL, 70°C, 30min | clear | 7.4 | 8.8±1.2 | 118% | |
|
| ||||||
| Ni (0) metallic | ammonium citrate (Sol A) | 10mL, 37°C, 60min | residue | 4.6 | / | / |
| H2O2 citrate: ammonium citrate (Sol B) | 10mL, ΔT, 60min | residue | 12.2 | 0.5±0.1 | 4% | |
| solution methanol: Bromine (solution C) | 10mL, ΔT, 2h | clear | 8.7 | 9.2±1.1 | 105% | |
| Solution HCl: HNO3 1:1 (Sol D) | 4mL, 70°C, 30min | clear | 13.4 | 15.7±2.3 | 117% | |
|
| ||||||
| NiO | ammonium citrate (Sol A) | 10mL, 37°C, 60min | residue | 7.0 | / | / |
| H2O2 citrate: ammonium citrate (Sol B) | 10mL, ΔT, 60min | residue | 13.4 | 0.1±0.1 | 1% | |
| solution methanol: Bromine (solution C) | 10mL, ΔT, 2h | residue | 7.4 | / | / | |
| Solution HCl: HNO3 1:1 (Sol D) | 4mL, 70°C, 30min | clear | 10.4 | 11.8±3.2 | 114% | |