> Synthesis of antimony trioxide
Synthesis of antimony trioxide
2013-11-23 by seoer8
Divided into dry and wet. Dry by stibnite or antimony trioxide metal was calcined product of oxidation method. Wet is stibnite or antimony metal with an acid liquid phase using the method prepared by the reaction products. 1 dry stibnite (Sb2S3) calcined at 1000 ℃ in the presence of coke. The oxidation of antimony trioxide vapors collected and condensed, the flux used to make soda ash, and the reduction of coke generated by heating the metal antimony. The resulting metal antimony and then oxidized in air to obtain antimony trioxide. The reaction is: 2 wet metal antimony salts ammonolysis reaction of chlorine and antimony, antimony trichloride, separated by distillation, hydrolysis, ammonia solution, washed, centrifuged, and dried to obtain trioxide product. As raw materials in stibnite stibnite hydrochloric acid method and hydrochloric acid, the reaction occurs in the presence of nitric acid by hydrolysis, precipitation, drying derived products. 3 from a metal melting or burning antimony prepared in air. 4 is the relative density of such mixture of hydrochloric acid and 1.19 volumes of water, under stirring, antimony trichloride dissolved therein, and then
Sodium carbonate solution was added slowly to boiling, and continue to boil: When there is no evolution of CO2 gas, the heating was stopped and the precipitate was isolated, washed with water until free of Cl-ions in the washing after drying at 150 ℃ dry, you can. 5 to 7kg purity antimony trichloride dissolved by heating under stirring constantly, slowly added to 90L of boiling water conductivity, a white precipitate to form a mixed antimony trioxide and antimony oxychloride. 28% purity was added to the aqueous ammonia solution pH = 8-9, allowed to stand until precipitation was complete, filtered, the precipitate was then heated to boiling water 50L thermal conductance, pH adjusted with high-purity ammonia = 8-9, repeated 5 times to the solution without Cl-ions, filtered after drying 120 ℃ 16h, to obtain high-purity antimony trioxide (99.99%). 4 stibnite stibnite law to raw materials for the preparation of antimony trioxide, reaction is as follows:
Stibnite concentrate mix containing more than 60% of antimony and coke, put at 800 ~ 1000 ℃ roasting furnace, and strictly control the temperature and roasting furnace oxidizing atmosphere to ensure complete oxidation of stibnite crude oxidation antimony. Volatile trioxide gas together into the furnace cooling system, rapidly cooled to less than 150 ℃, collected in the bag crude antimony. Then into the reduction furnace, the coke in the presence of an alkali metal as a flux to a heat reduction of antimony. Then the metal antimony into the furnace temperature was controlled at about 1000 ℃, through air oxidation of antimony trioxide into vapor by condensation system cooling, collect the product were in the bag.