The enhancement of gibbsite precipitation in Bayer process by 33 kHz ultrasound has been studied. From orthome-thod experiment, the optimized operating parameters of treatment under 33 kHz ultrasonic cleaner have obta...The enhancement of gibbsite precipitation in Bayer process by 33 kHz ultrasound has been studied. From orthome-thod experiment, the optimized operating parameters of treatment under 33 kHz ultrasonic cleaner have obtained. Compared with crystallization of AI(OH)3 without treatment of ultrasound, the precipitation time is reduced by 15 h when the precipitation ratio is 45%. From the results of grain size distribution and SEM photographs of gibbsite, it is found that secondary nucleation and agglomeration could be enhanced under 33 kHz ultrasound. The products are same from comparison of X-ray powder diffraction, but the Raman spectrum of sodium aluminate solution under 33 kHz ultrasound is different from that without ultrasound.展开更多
Large trihydroxy bauxite deposit was once considered unavailable in China.With the prospecting think-ing of diwa theory,the author has drawn a contrary conclusion.From the view of the law of progression with transform...Large trihydroxy bauxite deposit was once considered unavailable in China.With the prospecting think-ing of diwa theory,the author has drawn a contrary conclusion.From the view of the law of progression with transformation between mobile and stable regions and the metallogenic specialization of tectonic elements,he reveals the principal reason why the known bauxite deposits in China are mostly of monohydroxide type,and acquires the way of searching for trihydroxide bauxite deposits.He considers that the residual-mobility period of the diwa stage in the crustal development in South China pocesses-tectonic conditions favourable to the formation of bauxite deposits of this type.He believes that the Cenozoic structural sublayer of the residual-mobility period of the diwa stage developed on the carbonate rock of the Paleozoic platformal structural layer is the preferrential target of prospecting.With this thinking and many years of efforts,we have gained prelimi-nary achievements and have discovered Guigang-type latee-ritic trihydroxied bauxite deposits in Guangxi.In future,by extension and analogy of the thinking,we are likely to find large,high-grade bauxite deposits in its vicinity and to discover weathering-type bauxite deposits with other parent rocks.展开更多
基金The authors would like to acknowledge the support by the National Priority Development Project Fundamental Research(G1999064902-3)the National Natural Science Foundation of China(59874031).
文摘The enhancement of gibbsite precipitation in Bayer process by 33 kHz ultrasound has been studied. From orthome-thod experiment, the optimized operating parameters of treatment under 33 kHz ultrasonic cleaner have obtained. Compared with crystallization of AI(OH)3 without treatment of ultrasound, the precipitation time is reduced by 15 h when the precipitation ratio is 45%. From the results of grain size distribution and SEM photographs of gibbsite, it is found that secondary nucleation and agglomeration could be enhanced under 33 kHz ultrasound. The products are same from comparison of X-ray powder diffraction, but the Raman spectrum of sodium aluminate solution under 33 kHz ultrasound is different from that without ultrasound.
文摘Large trihydroxy bauxite deposit was once considered unavailable in China.With the prospecting think-ing of diwa theory,the author has drawn a contrary conclusion.From the view of the law of progression with transformation between mobile and stable regions and the metallogenic specialization of tectonic elements,he reveals the principal reason why the known bauxite deposits in China are mostly of monohydroxide type,and acquires the way of searching for trihydroxide bauxite deposits.He considers that the residual-mobility period of the diwa stage in the crustal development in South China pocesses-tectonic conditions favourable to the formation of bauxite deposits of this type.He believes that the Cenozoic structural sublayer of the residual-mobility period of the diwa stage developed on the carbonate rock of the Paleozoic platformal structural layer is the preferrential target of prospecting.With this thinking and many years of efforts,we have gained prelimi-nary achievements and have discovered Guigang-type latee-ritic trihydroxied bauxite deposits in Guangxi.In future,by extension and analogy of the thinking,we are likely to find large,high-grade bauxite deposits in its vicinity and to discover weathering-type bauxite deposits with other parent rocks.
