氧化铁对硫铝酸钙矿物形成的影响

借助化学分析方法、X射线衍射、差示扫描量热法等测试手段研究了Fe2O3对无水硫铝酸钙矿物(C4A3S)形成过程的影响.研究表明:掺杂Fe2O3可促进熟料中游离氧化钙(f-CaO)的吸收,增加液相量,改善C4A3-S矿物生料的易烧性;不掺杂Fe2O3的矿物生料,C4A3-S单矿物在850℃以下几乎不生成,在1 000℃开始大量生成,在1 300℃达到最高值;掺杂1?2O3的试样中C4A3S含量与不掺杂试样在同温度下达到最大值,但绝对含量有一定幅度的下降;掺杂3%及5?2O3的试样中C4A3S含量在1 350℃达到最大值,达到最大值的时间比原来延迟0.5h,并且绝对含量有较大幅度的下降;掺杂Fe2O3的试样在1 200℃至1400℃时,Fe3 和C4A3-S中的Al3 发生置换,使Fe3 固熔到C4A3-S中形成固熔体C4(A0.95F0.05)6O12(SO4).

EFFECT OF Fe2O3 ON THE FORMATION OF CALCIUM SULPHOALUMINATE MINERAL

Testing methods such as chemical analysis,X-ray diffraction and differential scanning calorimetry were used to study the influence of Fe2O3 on the formation of anhydrous calcium sulphoaluminate ( C4A3-S ).The results show that adulterating Fe2O3 can increase the quantity of liquid phase,boost the f-CaO absorption and also can improve the burnability of raw materials of C4A3-S mineral.C4A3-S mineral does not form at below 850 ℃,and large quantities of C4A3-S are formed at nearly 1 000 ℃.The maximum quantity of C4A3-S occurred at 1 300 ℃.The quantity of C4A3-S in specimens doped with 1% Fe2O3reaches the maximum at 1 300 ℃ too,the absolute quantity decreases in a degree.The quantity of C4A3S in specimens doped with 3% and 5% Fe2O3 reaches the maximum at 1 350 ℃,there was a half-hour time delay compared with the specimens without Fe2O3 and the absolute quantity has a great drop.The Fe3+ in the specimen doped with Fe2O3 is replaced with Al3+ at 1 200 ℃ to 1 400 ℃,which causes Fe3+ to melt into C4A3S to form C4(A0.95F0.05)6O12(SO4).