The Property And Preparation of Manganese Oxide Mn2O3 Powder
Views : 422
Update time : 2020-12-14 10:23:05
The Property of Manganese Oxide
The chemical formula of manganese oxide is Mn₂O₃ and the molecular weight is 157.88. It is a black cubic crystal with a relative density of 4.50. Manganese oxide is insoluble in water, acetic acid and ammonium chloride solution, but soluble in other inorganic acids.
Manganese oxide dissolves in cold hydrochloric acid to form a brown solution, turns into a red solution in hot dilute sulfuric acid or concentrated sulfuric acid, decomposes into MnO₂ and manganese nitrate in hot nitric acid, and decomposes into Mn₃O₄ by heating and releases O₂. It exists in two forms: α-Mn₂O₃ and γ-Mn₂O₃.
The Preparation Methods of Manganese Oxide
Preparation of α-Mn₂O₃
α-Mn2O3 can be further oxidized or reduced by manganese oxide, or it can be prepared by heating divalent manganese salt in the air at 600-800°C. The easiest method is to heat manganese nitrate hexahydrate or pure β-MnO2 in air at 650°C to constant weight. When manganese nitrate hexahydrate is used as a raw material, it needs to be heated at 190°C in advance to make a solid, then crush it and heat it at 650°C.
Preparation of γ-Mn₂O₃
In 350 mL of a solution containing 2.2 g of manganese sulfate tetrahydrate, under vigorous stirring, 34 mL of 3% hydrogen peroxide solution was added dropwise, followed by 50 mL of 0.2 mol·dm-3 ammonia to generate γ-MnO(OH). The dark brown or black suspension that emits oxygen is quickly boiled by heating. After boiling for 4 minutes, filter and separate, wash the solid with 1.5L hot water, and put it in a vacuum desiccator with phosphorus pentoxide, below 100℃ After drying, γ-MnO(OH) is obtained. This γ-MnO(OH) was carefully dehydrated at 250°C under reduced pressure for 3 days to produce γ-Mn2O3. In addition, γ-MnO2 can be heated at 500°C for 78 hours under reduced pressure to prepare γ-Mn2O3.
Luoyang Trunnano Tech Co., Ltd (TRUNNANO) is a professional manganese oxide with over 12 years experience in chemical products research and development. If you are looking for high quality manganese oxide, please feel free to contact us and send an inquiry.
