Study on preparation and properties of supported compound desulfurizer for Bayer dissolution

Abstract

In view of the serious harm caused by sulfur ion to alumina production and the high cost of desulfurization in Bayer dissolution process of high sulfur bauxite leaching at high temperature and high pressure, the supported compound desulfurizer was prepared by melt infiltration method to realize simultaneous desulfurization in Bayer dissolution process. In this paper, Zn(NO3)2·6H2O and Cu(NO3)2·3H2O as the main components, kaolin, sepiolite, activated alumina as the active carrier, the supported compound desulfurizer was prepared. The active carrier was optimized and the optimum preparation parameters were determined by means of DSC, IR, TG, SEM and XRD. The results show that kaolin is more suitable as the active carrier of compound desulfurizer. The best melting temperature of the precursor is 100 °C, the best calcination temperature is 400 °C, and the best calcination time is 2 h. The supported compound desulfurizer mainly consists of ZnO, CuO, AlOOH, SiO2 and Mullite. The results provide a basis for the active preparation of the supported compound desulfurizer.