Reaction behavior and conversion of anatase in alumina production process with calcification-carbonization method

摘要

The reaction behavior and conversion of anatase in therncalcification-carbonization process were investigatedrnexperimentally in the pure substance systems ofrnNa_2O-Al_2O_3-CaO-TiO_2-H_2O andrnNa_2O-Al_2O_3-SiO_2-CaO-TiO_2-H_2O. The calcificationrnexperiments were conducted respectively in therndigestion conditions of diaspore and gibbsite. Inrncalcification process, with temperature increasing,rnanatase converts to firstly Ca3TiSi2(Al_2Si_(0.5)Ti_(0.5))O_(14)rnand then CaTiO_3. The increase of sodium aluminaternsolution concentration and additive TiO_2-SiO_2 ratiorncan promote this conversion. In carbonization process,rnCO_2 can’t make CaTiO_3 decompose. CaTiO_3 is thernmost stable titanate phase inrncalcification-carbonization process.