Aluminous compound

The content of aluminum in the earth's crust is relatively high

Mainly in aluminosilicate ore, as well as bauxite and cryolite Alumina is a kind of white amorphous powder, which has many variants, of which the most familiar is α－ Al‹o ₃ and β－ Al₂O₃。 Corundum existing in nature belongs to α An Al 2O ₃, its hardness is second only to diamond, with high melting point and acid and alkali resistance. It is often used to make some bearings, abrasives and refractory materials. Such as corundum crucible, it can withstand high temperature of 1800 ℃. Al‹o ₃ has many colors due to different impurities. For example, those containing trace Cr (III) are red and called ruby; Sapphire contains Fe (II), Fe (III) or Ti (IV).

β Al 2O 3 is a porous material with an internal surface area of hundreds of square meters per gram. It has high activity, also known as activated alumina. It can adsorb many gas and liquid molecules such as water vapor. It is often used as adsorbent, catalyst carrier and desiccant. Aluminum smelting in industry also uses it as raw material.

Aluminum hydroxide can be used to prepare aluminum salt, adsorbent, mordant and ion exchanger, and can also be used as raw materials such as enamel, refractory, fireproof cloth, etc. its gel solution and thousand gel are used as acid drugs in medicine, which have the effects of neutralizing gastric acid and treating ulcer, and are used to treat stomach and duodenal ulcer disease and hyperacidosis.

Sodium metaaluminate is commonly used in printing and dyeing fabrics, producing lake blue dyes, making glass wool rot, soap, and hardened building stones. In addition, it is also a good water softener, paper-making filler, water purifier, rayon degumming agent, etc.

Anhydrous aluminum chloride is a common catalyst in petroleum industry and organic synthesis; For example, the alkylation reaction of aromatics, also known as Friedel Kraft alkylation reaction, is catalyzed by anhydrous aluminum trichloride. Aromatics and halogenated hydrocarbons (or olefins and alcohols) undergo electrophilic substitution reaction to produce alkyl substitutes of aromatics. Aluminum chloride hexahydrate can be used to prepare deodorant, safe disinfectant and petroleum refining.

Aluminum bromide is a commonly used catalyst for organic synthesis and isomerization.

Aluminum phosphide emits highly toxic phosphine gas in case of moisture or acid, which can poison pests. It is a fumigant used in agriculture to kill insects in barns.

Aluminum sulfate is commonly used as filler, mordant, water purifier and fire extinguishing agent in papermaking, oil clarifier, oil deodorizer and color remover, and is also used in the manufacture of precipitated colorants, fireproof cloth and drugs.

Cryolite, namely sodium hexafluoroaluminate, is commonly used as insecticide in agriculture; Opalescent used in the silicate industry to make glass and enamel.

Alum prepared from alunite by heating and extraction is an important water purifier and dye agent, which is used as astringent in medicine. Aluminum nitrate can be used for tanning and white thermoelectric filament, and can also be used as mordant; Aluminum silicate is often used to make pigments for glass, ceramics, paints and fillers for paints, rubber and plastics. Silicon aluminum gel is hygroscopic and is often used as a catalyst carrier for petroleum catalytic cracking or other organic synthesis.

In carboxylate of aluminum; Aluminum dicarboxylate and aluminum tricarboxylate are commonly used as mordant, waterproof agent and bactericide; In addition to being used as mordant, aluminum diacetate is also used as sword collector and disinfectant, as well as in body antiseptic liquid; Aluminum triacetate is used to make waterproof and fireproof fabrics and lakes; Drugs (gargle, astringent, antiseptic, etc.) and used as mordant, etc; Aluminum octadecanoate (aluminum stearate) is commonly used as anti sedimentation agent of paint, waterproof agent of fabric, thickening agent of lubricating oil, antirust agent of tools, heat-resistant stabilizer of PVC plastic, etc; Aluminum oleate is not only used as a waterproof agent for fabrics and thickening agent for lubricating oil, but also used as a drying agent for paint and a lubricant for plastic products.

Sucralfate, also known as weikuining, and its scientific name is sucrose sulfate basic aluminum salt. It can complex with pepsin, directly inhibit protein decomposition activity, and has a long-lasting effect. It can form a protective film, which has a strong protective effect and acid making effect on gastric mucosa, helps mucosa regeneration, promotes ulcer healing, and has low toxicity. It is a good therapeutic agent for gastrointestinal ulcer.

In recent years, people have developed some new aluminum containing compounds, such as alkyl aluminum. With the development of science, people will make better use of aluminum and its compounds to benefit mankind.