The mineral transition mechanism and physicochemical property of calcium aluminate clinker sintered at 1350 ℃ were systematically studied using analytical reagent α-Al 2O 3,CaCO 3 and SiO 2 when the molar ratio of C...The mineral transition mechanism and physicochemical property of calcium aluminate clinker sintered at 1350 ℃ were systematically studied using analytical reagent α-Al 2O 3,CaCO 3 and SiO 2 when the molar ratio of CaO to Al 2O 3 is 1.0.The results show that the formation of Ca 2SiO 4 accelerates the diffusion of CaO and Al 2O 3,which promotes the formation of CaAl 2O 4 determined by dilatometer,X-ray diffraction,Fourier transform infrared spectroscopy and scanning electron microscopy methods.CaAl 4O 7,Ca 3Al 2O 6,Ca 3SiO 5 and Ca 2Al 2SiO 7 only exist in the initial stage of reactions,the amounts of which decrease with the increase of sintering duration.Ca 3Al 2O 6 and Ca 12Al 14O 33 react with Al 2O 3 and CaAl 4O 7 to form CaAl 2O 4,while Ca 2Al 2SiO 7 reacts with CaO and Ca 12Al 14O 33 to form Ca 2SiO 4 and CaAl 2O 4.The sintered clinker contains CaAl 2O 4 and γ-Ca 2SiO 4 as well as some Ca 12Al 14O 33 when the sintering duration is longer than 1.0 h.The differential scanning calorimetry results reveal that Ca 2SiO 4,Ca 2Al 2SiO 7 and CaAl 2O 4 are formed at985 ℃,1045℃ and 1339 ℃,respectively.Increasing the sintering duration contributes to the transition of β-Ca 2SiO 4 to γ-Ca 2SiO 4,which improves the pulverization and alumina leaching property of the sintered clinker.展开更多
基金financial support of the project from the National Natural Science Foundation of China (Nos.51174054,51104041 and 51374065)the Fundamental Research Funds for the Central Universities (No.N130402010)
文摘The mineral transition mechanism and physicochemical property of calcium aluminate clinker sintered at 1350 ℃ were systematically studied using analytical reagent α-Al 2O 3,CaCO 3 and SiO 2 when the molar ratio of CaO to Al 2O 3 is 1.0.The results show that the formation of Ca 2SiO 4 accelerates the diffusion of CaO and Al 2O 3,which promotes the formation of CaAl 2O 4 determined by dilatometer,X-ray diffraction,Fourier transform infrared spectroscopy and scanning electron microscopy methods.CaAl 4O 7,Ca 3Al 2O 6,Ca 3SiO 5 and Ca 2Al 2SiO 7 only exist in the initial stage of reactions,the amounts of which decrease with the increase of sintering duration.Ca 3Al 2O 6 and Ca 12Al 14O 33 react with Al 2O 3 and CaAl 4O 7 to form CaAl 2O 4,while Ca 2Al 2SiO 7 reacts with CaO and Ca 12Al 14O 33 to form Ca 2SiO 4 and CaAl 2O 4.The sintered clinker contains CaAl 2O 4 and γ-Ca 2SiO 4 as well as some Ca 12Al 14O 33 when the sintering duration is longer than 1.0 h.The differential scanning calorimetry results reveal that Ca 2SiO 4,Ca 2Al 2SiO 7 and CaAl 2O 4 are formed at985 ℃,1045℃ and 1339 ℃,respectively.Increasing the sintering duration contributes to the transition of β-Ca 2SiO 4 to γ-Ca 2SiO 4,which improves the pulverization and alumina leaching property of the sintered clinker.
