【摘要】 在合成超微细CaCO3的非稳态体系中，通过电导率仪、pH计、SEM以及化学分析等手段，跟踪测定了添加剂Na5P3O10存在时Ca（OH）2悬浮液的碳化过程．结果表明，Ca（OH）2的碳化分为两个阶段：初期的恒速反应阶段和末期的变速反应阶段．在恒速阶段，碳化的表现反应级数为－2，碳化反应速率随Na5P3O10浓度的增加而减小．在变速阶段，碳化的表现反应级数也随Na5P3O10浓度的增加而减小．提出了在恒速反应阶段碳化过程由Ca2＋和CO2-3反应速度控制，CO2吸收的影响可以忽略，变速反应阶段由Ca（OH）2溶解和Ca2＋及CO2-3反应速度控制的传质模型．更多还原

【Abstract】 The carbonation of Ca(OH)2 suspension in the presence of Na5P3O10 was examined by conductivity pH measuxemenis and chemilcal analysis, and the reaction products were determined by SEM. The results show that the carbonation can be divided into two stages: the constant rate period and the rate-changing one. During the constant rate period, an apparentorder n=-2 was obtained, and n decreased with the increase of Na5P3O10 in the rate-decreasing period. A mass transfer model was put forward that the carbonating rate was iultially controlled by the reaction of Ca2+ with CO2-3 in the constant rate period, and finally became controlled by dissolution of Ca(OH)2 and reaction of Ca2+ with CO2-3. The resistance dueto absorption of CO2 in the overall process is negligible. It was noted that the presence ofNa5P3O10 in the Ca(OH)2 suspension at a level as low as (0.3804~1.522)×10-4 mol/L wasenough to completely inhibit the reaction.更多还原