Preparation of high temperature-resistant active aluminum oxide

Abstract

The invention relates to a method for preparing fireresistant activated alumina. A liquid phase counter-titration precipitation method is adopted; a sodium aluminate solution and a nitric acid solution are used as raw material; organisms are used as a pore expanding agent; a rare earth oxide is used as a stabilizing agent; the alumina with large specific surface area and good fireresistant performance is prepared by adopting the liquid phase counter-titration precipitation method. The rare earth oxide content in the alumina is between 0.1 and 10 wt percent; an alumina solid is treated for 5 hours in the atmosphere of 700 DEG C; the specific surface area of the alumina solid is more than 350m <2> / g; the average pore volume is 0.3122 mL / g; the average aperture is 5.23 nm; and the aperture distribution range is between 3 and 12 nm. The alumina solid is treated for 5 hours in the atmosphere of 1100 DEG C; and the specific surface area of the alumina solid is more than 150 m <2> / g. The method has the characteristics of low production cost, simple process, large specific surface area, even aperture distribution and good high-temperature thermal stability.

Description

technical field [0001] The invention relates to the field of alumina preparation, in particular to a preparation method of high-temperature resistant activated alumina. Background technique [0002] With the advancement of science and technology and the rapid development of social economy, as an important means of transportation, the automobile industry has developed rapidly. At present, the number of cars in the world has exceeded 600 million, and is increasing at a rate of 50 million per year. By 2010, the number of cars in the world will increase to 1 billion. my country's automobile industry is also developing rapidly. The current social ownership is more than 14 million vehicles. According to experts' prediction, in the next 10 to 15 years, China's automobile ownership will grow at an average annual rate of 9%. Cars mainly use fuel as the main power, and the gas released contains a variety of harmful gases, and its main components include carbon monoxide, hydrocarbons ...

AI Technical Summary

Problems solved by technology

The three-way catalyst is mainly composed of carrier, coating (the main substance is alumina) and active components. Since the temperature of automobile exhaust often reaches very high temperature, it is easy to make γ-Al 2 o 3 surface sintering and α-Al 2 o 3 Crystal transformation, which will cause Al 2 o 3 The surface area is drastically reduced and the catalyst loses activity

In recent years, researchers at home and abroad have conducted a lot of research on improving the thermal stability of alumina, but with little success. Therefore, improving the high-temperature anti-sintering and anti-α phase transition of the catalyst coating is the key to improving the quality of the catalyst and prolonging its life. Problems that need to be solved urgently