Effect of 20kHz ultrasound on alumina hydrate precipitation from seeded sodium aluminate solution

摘要

The effect of 20kHz ultrasound on alumina hydrate precipitation from seeded sodium aluminate solution was studied. Compared with alumina hydrate precipitation without treatment of ultrasound, the precipitation time is reduced from 30h to 15h when the precipitation ratio is 45% under 20kHz ultrasound. Furthermore, agglomeration is increased and the growth rate of alumina hydrate is increased under 20kHz ultrasound by comparing the crystal size distribution and the SEM photographs. As a result, the average size of alumina hydrate is increased by 3.7μm. The structure of product is not changed according to the results of X-ray powder deflection.