Study On Preparation Of Pseudo-boehmite Using Red Mud Wash Solution

Pseudo-boehmite is a kind of transient products,composed uncertainty, crystallized incompletely from disorder to order, crystal to the weak.It is mainly used for preparating raw materials and molecular sieve ofγ-Al2O3,α-Al2O3 and difficult molding catalyst or the binder of such catalysts.In this paper the preparation process of pseudo-boehmite by using red mud lotions was studied.The concentration of dilute liquid and CO2, decomposition temperature, the pH value of end carbonization, aging medium, temperature, time, washing and drying process were considerated especially which have impact on the structure performance of pseudo-boehmite.Then process conditions were concluded:the concentration of Al2O3 is 40～50 g/L, decomposition temperature is below 40℃,the pH value of end decomposition is 10.5, the volume fraction of CO2 is greater than or equal to 33%; the temperature of aging is no less than 90℃,the time of aging is greater than 3 hours;the times of washing is more than 3,the temperature of drying is below 100℃. Industrial expanded experiment was done in the real production line. And the experiment results show that, the preparation process of pseudo-boehmite by using red mud lotions is feasible in technic, the analysis indexes of pseudo-boehmite produced by this way accord with the enterprise standard, and it can achieve the use requirement. The economic benefit is analyzed finally.The results show that the application of red mud lotions can reduce the quantity of water and the production cost of pseudo-boehmite and Al2O3.While Al2O3 and Na2O in the red mud lotions can be recycled to using.