Mercury sulfide (HgS)

Mercury sulfide is an inorganic compound, a fine, bright red powder. It is insoluble in water and alcohol. It has two variants, open mercury sulfide (alpha form) is red hexagonal crystals or powder; relative density 8.10, sublimation at 583.5℃, insoluble in water, soluble in concentrated sodium sulfide solution, insoluble in alcohol and nitric acid. Beta form is black cubic crystals or amorphous powder, relative density 7.73, melting point 583.5℃, insoluble in water, alcohol and nitric acid, soluble in concentrated solutions of alkali metal and alkaline earth metal sulfides.

Dry method (sublimation method) production. Reaction equation: Hg+S→HgS black mercury and sulfur powder with an excess of about 15% to 20% calculated according to the reaction formula are melted at 140 to 160°C to form black mercury sulfide. Stir properly during the reaction, turn the material up, increase mercury Contact area with sulfur. The combination of sulfur and mercury is an exothermic reaction, so the temperature should be lowered in time to avoid spontaneous combustion of sulfur. In the air isolation, at 600 ~ 650 ℃, black mercury sulfide can be sublimated into red mercury sulfide. After the sublimated red mercury sulfide is taken out and crushed to a fineness of 80 to 100 meshes, an appropriate amount of water is added to grind the surface pigment slurry in a stone mill or a ball mill. The principle of gravity sedimentation is used to separate the particles with a large particle size in the pigment slurry to collect the pigment particles within a certain size range. During the separation, add 1 to 1.2 times the weight of the dry material and 0.5% to 0.7% of water-soluble surfactant, and fully stir to disperse it into a suspension. After standing for 1~1.5h, the coarse particles with a larger particle size than the vermilion will quickly settle down due to gravity. The vermilion particles and the particles with a smaller particle size than the vermilion will become suspended due to the adsorption effect of the surfactant and settle. The speed is much slower. Keeping the same settling time every time can collect particles of the same size range, so that the color tone of each batch of products can be consistent. After sedimentation and separation, the upper suspension is sent to the rinsing pond. The coarse particles settled at the bottom of the separation tank absorb the water, mix with the crushed red mercury sulfide and return to grinding. The coarse particles back-milled account for approximately 55% to 60% of the weight of the grinding material. Add 1.2 to 1.5 times the volume of water during rinsing, precipitate after full stirring for 24h, due to the weakening of the surfactant after dilution, the vermilion pigment settles down in the rinsing pond, put away the rinsing water, take out the vermilion and bake at 90-100 ℃ Dry and crush to get the finished product. The particle size of the prepared vermilion is approximately in the range of 5-15 μm. Wenfa production. Reaction equation: Hg+Na2Sx→Na2Sx-1 +HgS black x>3 HgS black [Na2S(x-1)]→HgS red mercury reacts with Na2Sx at 45～60℃ for a long time to produce black mercury sulfide, and at the same time Dissolve in Na2S(x-1) to produce Na2[HgS2]·5H2O. When dissolved to saturation, Na2[HgS2]·5H2O under the influence of S2-, the crystal lattice rearranged and transformed into red mercury sulfide.

For coloring plastics, sealing wax, and with FeSO4 for marking linen; manufacture of fancy colored papers; as pigment.

Molecular Weight:232.66
Hydrogen Bond Acceptor Count:1
Exact Mass:233.942715
Monoisotopic Mass:233.942715
Topological Polar Surface Area:32.1
Heavy Atom Count:2
Complexity:2
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes