2016年1月13日星期三

What is Pseudoboehmite?

Pseudoboehmite is also called pseudo boeohmite or False monohydrate soft diaspore, which is alumina crystals containing 1.8 -2.5 crystallization water molecules. It is the first crystal phase in the synthesis of aluminum hydroxide, which is the transition of aluminum hydroxide. And its crystallization is incomplete, The typical crystal shape is a very thin folded wafer. When comparing pseudoboehmite with aluminium hydroxide, you could see pseudoboehmite has incomplete crystallization water molecules,. Therefore has many special properties, such as space mesh structure, larger pore gap, higher surface area, and it will become sticky colloidal thixotropy in acid condition etc. All these features make pseudoboehmite has special application.

In modern oil refining and chemical industry, more than 90% chemical reaction process are implemented through catalytic process, thus catalyst has become a new technology of oil refining and new chemical technology and new product development. Solid catalysts are generally used in the oil refining industry, it is by the carrier and active component of two parts. Carrier is peculiar to the solid catalyst component, which can increase the specific surface area, heat resistance and mechanical strength. It is the active component of dispersant, binder, or support.

Catalytic cracking is the most important Secondary processing procedure in the current oil refinery, and an important means of production of light oil, especially high octane number gasoline. Catalytic cracking (FCC) catalyst is the core of the catalytic cracking process. Zibo Xiangrun in the production of ordinary pseudoboehmite, mainly used for catalyst carrier in oil catalytic cracking (FCC) . As the heavy crude oil and inferior crude oil in the world, blending heavy oil, residual oil has become a widely used way of processing of oil, so it requires oil catalytic cracking (FCC) catalyst has big hole to to diffuse heavy oil molecular, and improve the catalyst cracking ability of macromolecular compounds in raw materials with appropriate acid density. To satisfy this requirement, people usually adopts two methods: one is the modified Y zeolite make twice big hole, the second method is introducing high hydrothermal stability of solid acid catalyst compound to improve the pore size distribution and acidic density of active center. Currently the second approach is widely used, namely by adding activated alumina catalyst to improve catalyst substrate.



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