Product name: Boron tribromide

CAS: 10294-33-4

Molecular formula: BBr3

Molecular weight: 250.52

EINECS: 233-657-9

Introduction

Boron tribromide is an inorganic compound, a colorless liquid at room temperature, which reacts with moisture in the air to produce smoke and boric acid and hydrogen bromide. It can be prepared by heating boron trioxide, carbon and bromine: boron is first generated in the reaction, and then boron reacts directly with bromine to form a compound.

Boron tribromide Chemical Properties

Physical and chemical properties

Colorless fuming viscous liquid, highly irritating and toxic. Melting point -46℃, boiling point 91.3℃. Soluble in carbon tetrachloride. Easily decomposed by water and alcohol, decomposed by light or heat, and exploded by heat. Can react with phosphorus, nitrogen, oxygen, sulfur, halogen, ammonia, alkali, phosphorus halides, phosphine and many ammonia substitutes. Highly corrosive. Strongly irritating to skin, eyes or mucous membranes. Toxicity is similar to hydrogen bromide. The United States stipulates that the maximum allowable concentration of boron tribromide in the working environment air is 1ppm (10mg/m3). It is obtained in the laboratory by reacting aluminum tribromide with boron trifluoride and distilling it. It can be used as a doping source for semiconductor silicon and is also used in the preparation of high-purity boron and organic boron compounds. Other related chemical reactions involving boron tribromide: Boron tribromide is continuously introduced into hydroiodic acid at 300-400°C to obtain a mixture of BIBr2, BI2Br and BI3, which is then separated by distillation to obtain dibromoboron iodide. Boron tribromide reacts with adamantane to generate 1-bromoadamantane.

Chemical properties

Natural alkali is a monoclinic crystal system with plate-like crystals that are colorless, gray, yellow or brown. It is easily soluble in water. It has an alkaline taste.

Quenching method

Add to a large amount of ice water (do not add inversely) under stirring, and then neutralize with alkali after confirming the reaction. For phosphorus oxychloride that does not react immediately with ice water, slowly pour it into room temperature water, confirm that the reaction is complete, and then continue to add, add ice to cool from time to time, and finally neutralize with alkali under cooling. When handling, it can only be added slowly to water (alkali solution), and water must never be added to the above compounds.

Toxicity

Boron tribromide has a strong irritating effect on human tissues. Its vapor is highly toxic and corrosive. Wear a gas mask, gloves and protective clothing when operating. It is strictly forbidden to inhale vapor. If poisoned, send to hospital for treatment immediately.

Uses

1. It is the main chemical raw material for the production of caustic soda, baking soda and soda ash, and is widely used in the alkali industry

2. It is used as a doping source for semiconductor silicon, and can also be used for the preparation of high-purity boron and organic boron compounds

3. Natural alkali is mainly used to produce soda ash, caustic soda, baking soda and other products. Soda ash is an important industrial raw material, widely used in glass, chemical industry, light industry, textile, bleaching and dyeing, metallurgy, petroleum processing, medicine, food and other aspects. Caustic soda is mainly used in artificial fibers, papermaking, dyes, soaps, plastics, medicine, pesticides and other aspects. Baking soda is mainly used in food, plastics, rubber, medicine, printing and dyeing, tanning, agricultural seed soaking and other fields.

4. It is used as a doping material for semiconductors, a catalyst, intermediate and brominating agent for organic synthesis. It is a raw material for the manufacture of high-purity boron and other organic boron compounds.

5. It is used for organic boron synthesis and the preparation of high-purity boron

6. It is used as a catalyst, intermediate and brominating agent for organic synthesis, and a raw material for the manufacture of high-purity boron and other organic boron compounds.

Production method

1. Direct synthesis method: dry elemental boron powder is loaded into the reaction tube of the tubular reactor. In order to make the reaction fully proceed, a certain amount of filler should be placed in the reaction tube. The filler material is the same as the tube wall. Heat the reaction tube to 850℃, and heat the bromine in the bromine kettle to a slight boil at the same time, and then pass it into the reaction tube. The boron bromide liquid generated by the reaction is heated and refluxed together with activated carbon, zinc powder and aluminum chips in the debrominator until the generated boron bromide is colorless, and then crude distillation and rectification are performed to obtain a completely colorless boron bromide product. Its 2B+3Br2→2BBr3

2. Salt lake alkali mines are generally mined in open-pit mining, and ancient alkali mines are generally mined by underground dissolution. Mining and selection process 1. Open-pit mining 2 Underground dissolution method