Classification of pseudo boehmite

Pseudoboehmite, also known as alumina monohydrate and pseudoboehmite, with molecular formula of Al2O3 · nH2O (n=0.08-0.62), is non-toxic, tasteless, odorless, white colloidal (wet product) or powder (dry product), with high crystal phase purity, good gel solubility, strong cohesiveness, high specific surface area, large pore volume and other characteristics, and its aqueous state is thixotropic gel. It is mainly divided into the following four types:

(1) General pseudo boehmite

This type of pseudo boehmite requires high crystal purity, good solubility, and strong adhesion. It can be used as a binder for semi composed rare earth Y-type molecular sieve cracking catalysts, for aluminum silicate refractory fibers, as a catalyst for alcohol dehydration to ethylene, and as a catalyst for ethylene oxide.

(2) Special pseudo boehmite

This type of pseudo boehmite requires high crystal purity and good formability. Primary preparation γ- Al2O3 is a catalyst carrier used for catalytic hydrogenation in petroleum refining.

(3) Lightweight aluminum adhesive

The requirements include good molding performance, strong adhesion, small bulk density, and low sulfide content. In the production of catalysts, materials are used as methanation catalysts and catalysts for exhaust gas incineration containing organic compounds, as well as materials for various aluminum salts.

(4) Aluminum silicone

The SiO2 content in this type of pseudo boehmite can reach up to 26%~31%, with a demand for small bulk density, large specific surface area, large pore volume, and low sulfur content. It can be used as an adsorbent, a material for petroleum refining catalysts, and has high activity for hydrocracking catalysts. It can also be used for hydrogenation disposal catalysts.

Due to the strong bonding performance of pseudo boehmite and the ability to modify the substrate of the catalyst, its pore volume can be increased to 25%. Its selectivity can be improved to six units, and all these obvious characteristics can further develop and accelerate its future development trend.