镁钙砂碳酸化反应活化能与抗水化性能的研究

Study on Activation Energy of Carbonation of MgO—CaO and Anti—hydrability

采用TG—DTG技术,用多重升温速率方法,计算了镁钙砂颗粒表面碳酸化和水化碳酸化反应过程的表观活化能Ea,并对经碳酸化和水化碳酸化表面改性后的镁钙砂进行了抗水化性能测定。结果表明:镁钙砂水化碳酸化表观反应活化能Ea从单纯碳酸化时的189 kJ.mol-1降至155 kJ.mol-1;而经水化碳酸化表面改性后的镁钙砂的水化增重率则从单纯碳酸化时的0.95%降至0.43%。即镁钙砂碳酸化反应过程中水蒸气的引入提高了镁钙砂颗粒表面的反应活性,使其因碳酸化反应程度提高而抗水化能力增强。

The apparent activation energy Ea of carbonation of MgO-CaO coarse particles has been investigated by means of multiple scan method of TG-DTG technique in CO2 and CO2 and watervapor. And the hydrability of the carbonated particles has also been tested, it is found that its apparent activation energy of carbonation in CO2 and water vapor was down from 189 kJ· mol^-1,to 155 kJ·mol^-1, the former was got in CO2 ; While the mass increment of hydration of the particles carbonated in CO2 and water vapor decreased from 0.95 % got in CO2 to 0.43 % i.e. the particle＇ s surface was activated for existing of water vapor and accelerated its carbonation so that the anti - hydrability of MgO-CaO particles was increased.