Active lime was used to produce Ca(OH)2fine powder.And then Ca(OH)2fine powder with analytically pure CeO2fine powder(0,0.2%,0.4%,0.6%,0.8%and1.0%by mass,respectively)were mixed via wet mixing.After drying and b...Active lime was used to produce Ca(OH)2fine powder.And then Ca(OH)2fine powder with analytically pure CeO2fine powder(0,0.2%,0.4%,0.6%,0.8%and1.0%by mass,respectively)were mixed via wet mixing.After drying and ball milling,the specimens were pressed and fired at 1 450℃,1 500℃,1 550℃,1 600℃and1 650℃,respectively.The hydration resistance of the specimens was evaluated by measuring the mass gain after soaking the specimens in a chamber kept at 20℃and90%relative humidity.The influences of CeO2and calcination temperature on the hydration resistance of CaO aggregates were investigated by determination of bulk density,apparent porosity,and XRD,SEM and EDS analysis.The results show that:(1)the sintering of CaO aggregates is promoted by CeO2addition and the hydration resistance of CaO aggregates is improved;(2)CeO2mainly locates in CaO grain boundary,some CeO2is solved in the CaO grains which improves CaO sintering;(3)the appropriate calcination temperature is 1 550℃.When the calcination temperature is below 1 550℃,the specimens are sintered inadequately.The density and hydration resistance of CaO aggregates are nearly stable when the calcination temperature is above 1 550℃.展开更多
文摘Active lime was used to produce Ca(OH)2fine powder.And then Ca(OH)2fine powder with analytically pure CeO2fine powder(0,0.2%,0.4%,0.6%,0.8%and1.0%by mass,respectively)were mixed via wet mixing.After drying and ball milling,the specimens were pressed and fired at 1 450℃,1 500℃,1 550℃,1 600℃and1 650℃,respectively.The hydration resistance of the specimens was evaluated by measuring the mass gain after soaking the specimens in a chamber kept at 20℃and90%relative humidity.The influences of CeO2and calcination temperature on the hydration resistance of CaO aggregates were investigated by determination of bulk density,apparent porosity,and XRD,SEM and EDS analysis.The results show that:(1)the sintering of CaO aggregates is promoted by CeO2addition and the hydration resistance of CaO aggregates is improved;(2)CeO2mainly locates in CaO grain boundary,some CeO2is solved in the CaO grains which improves CaO sintering;(3)the appropriate calcination temperature is 1 550℃.When the calcination temperature is below 1 550℃,the specimens are sintered inadequately.The density and hydration resistance of CaO aggregates are nearly stable when the calcination temperature is above 1 550℃.