Does nickel sulfide precipitate?

Increasing the temperature and partial pressure of H2S(g) to 120 °C and 355 kPa causes precipitation of nickel as a sulfide from a solution at pH 3. Precipitation of NiS occurred when the pressure of H2S(g) was increased to 709 kPa at room temperature and nickel powder employed as a catalyst.

Is nickel sulfide soluble in water?

Nickel sulfide

Does NiS form a precipitate?

Nickel(II) sulfide is not precipitated by adding H2S in an acidic solution. In spite of this, NiS is only slightly soluble in HCl and has to be dissolved in hot nitric acid or aqua regia, because NiS changes to a different crystalline form with different properties.

What type of bond is nickel sulfide?

The optimized lattice parameters of these sulfides are within 1% of the values determined from x-ray diffraction. The electronic structure analysis indicates that all Ni–S bonds are strongly covalent.

How do you dissolve nickel sulfide?

NiS can be readily reactively dissolved with hot conc. nitric acid or with aqua regia, what is accompanied by sulfur precipitation.

Is nickel sulfide toxic?

Unusual Fire and Explosion Hazards: When heated to decomposition, nickel sulfide may emit toxic fumes of oxides of sulfur. Effects of Exposure: Nickel is a confirmed carcinogen with experimental carcinogenic, neoplastigenic, tumorigenic and teratogenic data.

How do you precipitate nickel?

Colorless sodium hydroxide solution is added to green nickel(II) nitrate solution. Approximately 2 mL of Solution A (on the left) is added to a sample of Solution B (on the right) with a dropping pipet. If a precipitate forms, the resulting precipitate is suspended in the mixture.

Why is Ni DMG 2 red?

The chelation reaction of nickel ions with the organic bidentate ligand dimethylglyoxime (DMG)1 in an alkaline ammonia medium producing nickel dimethylglyoxime, Ni(DMG)2, a red cherry or raspberry colour precipitate has been known since 1905 when it was discovered by Russian chemist Lev Aleksandrovich Chugaev (see …

What is the formula of nickel II sulfide?

NiS
Nickel sulfide/Formula

What is the formula for nickel II sulfide?

Is nickel sulfide flammable?

Fumes from fire are hazardous. Isolate runoff to prevent environmental pollution. Unusual Fire and Explosion Hazards: When heated to decomposition, nickel sulfide may emit toxic fumes of oxides of sulfur.

At what pH does nickel precipitate?

10-10.5
1, the best-compromised pH for hydroxide precipitation process is pH 10-10.5 for nickel, pH 9.0-9.5 for zinc and pH 8.5-9.5 for copper. It shows that these heavy metals cannot be completely removed at single pH range.

How is sulfide precipitation used to remove nickel?

Sulfide sludge is commonly generated from sulfide precipitation of nickel in wastewater. Therefore, the valorization of this material would have a higher industrial interest. Currently, the main disposal routes include landfills, incineration and pyrolysis (Xu et al. 2015).

How is sulfide precipitation of heavy metals measured?

Samples of actual wastewaters from 14 metal working industries (including Boeing) were processed through the bench-scale equipment using all five processes. Reductions in the concentrations of cadmium, chromium, copper, nickel, and zinc, plus selected other metals, were measured by atomic absorption chemical analysis.

How to calculate the yield of nickel removal?

The yield of nickel removal can be calculated as follows: where Ci is the initial concentration and Cf is the final concentration. The sludge generated from sulfide precipitation at optimal conditions was a black powder whose mass weight was approaching 48.93 mg.

How is nickel removed from electroplating industrial solution?

This work consists of the removal of nickel by sulfide precipitation from industrial electroplating wastewater and characterization of the produced sludge. Tests are carried out in a perfectly stirred batch reactor on electroplating industrial solution and synthetic solution prepared in the laboratory.