Technology for preparing pseudo-boehmite by sodium bicarbonate neutralization method

Abstract

The invention discloses a technology for preparing pseudo-boehmite by a sodium bicarbonate neutralization method, which comprises steps: using NaHCO3 solution and sodium aluminate solution to carry out acid-alkali neutralizing reaction so as to prepare pseudo-boehmite; and after neutralizing reaction, separating, ageing, washing, drying and grinding material to prepare pseudo-boehmite. As reactionmother solution does not contain acid radical ions, processes and devices are not corroded, and simultaneously CO2 gas is pumped into mother solution for depth carbonization to form NaHCO3 solution,and neutralization reaction can be conducted repeatedly, thus fully using production raw material and reducing production cost. The pseudo-boehmite prepared by the technology has good peptization property, fast peptization speed, high peptization rate, low peptization viscosity, concentrated product pore diameter distribution, good caking property and wide application in oil refining, petroleum and chemical industries, environmental protection and chemical fertilizer catalytic agent manufacture.

Description

technical field [0001] The invention relates to a preparation process of pseudo-boehmite, in particular to a process for preparing pseudo-boehmite by neutralizing a sodium aluminate solution and a sodium bicarbonate solution in an alumina production process. Background technique [0002] At present, alumina production enterprises produce pseudo-boehmite, and generally use sodium aluminate solution refined by desiliconization after ore dissolution as the raw material for producing pseudo-boehmite. 2 The product is prepared by gas carbonation decomposition method. The specific operation process is to prepare a sodium aluminate solution, and then inject CO into it. 2 gas. By controlling the different concentrations of alumina in the sodium aluminate solution, the reaction temperature, and the control of CO 2 The flow rate and speed of the gas, as well as the time of the entire precipitation process and the final precipitation end point, are used to produce pseudo-boehmite pro...

AI Technical Summary

Problems solved by technology

Its shortcomings are: the production process of alumina is an alkaline process, and it is most afraid of the pollution of acidic substances, such as using Al 2 (SO 4 ) 3 , AlCl 3 or HNO 3 and other acidic substances to neutralize the sodium aluminate solution to produce pseudo-boehmite, and the SO in the mother liquor after the reaction 4 2- , Cl - or NO 3- Such acidic anion substances will cause serious corrosion to the entire alumina production process and equipment, and the mother liquor will not be able to return to the alumina production process for utilization

[0003] Moreover, the existing enterprises use the carbonation method to produce pseudo-boehmite products, and adopt the method of introducing carbon dioxide gas into the sodium aluminate solution. Due to the influence of many factors in the production, the product performance is not stable enough, and the production capacity is limited. Very good to meet user needs