Overview of activated alumina
Activated alumina, also known as activated bauxite, is called activated alumina in English. Alumina used in catalysts is usually called “activated alumina”. It is a porous, highly dispersed solid material with a large surface area. Its microporous surface has the characteristics required for catalysis, such as adsorption performance, surface activity, excellent thermal stability, etc., so it is widely used as a catalyst and catalyst carrier for chemical reactions.
The spherical activated alumina pressure swing oil adsorbent is white spherical porous particles. The activated alumina has uniform particle size, smooth surface, high mechanical strength, strong hygroscopicity, does not swell and crack after water absorption, and remains unchanged. It is non-toxic, odorless, and insoluble in water and ethanol.
It is insoluble in water and can slowly dissolve in concentrated sulfuric acid. It can be used to refine metal aluminum and is also a raw material for making crucibles, porcelain, refractory materials and artificial gemstones.
Alumina used as adsorbent, catalyst and catalyst carrier is called “activated alumina”. It has the characteristics of porosity, high dispersion and large specific surface area. It is widely used in water treatment, petrochemical, fine chemical, biological and pharmaceutical fields.
Characteristics of alumina
1. Large specific surface area: activated alumina has a high specific surface area. By reasonably controlling the sintering system of alumina, activated alumina with a specific surface area as high as 360m2 / G can be prepared. The activated alumina prepared by using colloidal aluminum hydroxide decomposed by NaAlO2 as raw material has a very small pore size and a specific surface area as high as 600m2 / g.
2. Adjustable pore size structure: Generally speaking, products with medium pore size can be prepared by baking with pure aluminum hydroxide. Small pore size products can be prepared by preparing activated alumina with aluminum glue, etc. while large pore size activated alumina can be prepared by adding some organic substances, such as ethylene glycol and fiber, after combustion.
3. The surface is acidic and has good thermal stability.
Function of activated alumina
Activated alumina belongs to the category of chemical alumina, which is mainly used as adsorbent, water purifier, catalyst and catalyst carrier. Activated alumina has the ability to selectively adsorb water in gas, water vapor and some liquids. After the adsorption is saturated, it can be heated at about 175-315. D egree. Adsorption and reactivation can be carried out many times.
In addition to being used as a desiccant, it can also absorb lubricating oil vapor from contaminated oxygen, hydrogen, carbon dioxide, natural gas, etc. And can be used as a catalyst and catalyst support and as a support for chromatographic analysis.
It can be used as a defluorinating agent for high fluorine drinking water (with large defluorinating capacity), a defluorinating agent for circulating alkanes in the production of alkylbenzene, a deacidifying and regenerating agent for transformer oil, a drying agent for gas in oxygen making industry, textile industry and electronic industry, a drying agent for automatic instrument air, and a drying agent and a purifying agent in chemical fertilizer, petrochemical drying and other industries.
Post time: Jun-01-2022