硝酸胺溶液浸提硬硼酸钙的动力学研究

对硬硼酸钙在硝酸铵水溶液的溶解在间歇式反应器中就搅拌速度、粒径大小、反应温度、固液比和溶液的浓度等参数的影响进行了研究。结果表明溶解速度随温度、硝酸铵水溶液的浓度以及粒径和固液比的增加而增加，但搅拌速度对溶解速度无重要影响。硬硼酸钙在硝酸铵水溶液中可以高达100%。硬硼酸钙的溶解动力学根据多相和均相反应模型进行了检验。实验数据表明有高的活化能，说明基于多相反应动力学模型的溶解速度可表达为：1-(1-X)^1/3=3.28 ×10⁴·D^{-0.653 7}·C^{1.295 8}·(S/L)^{-0.490 9}·e^-41.40/(RT)·t。反应过程的活化能为41.40 kJ·mol^-1。

A Kinetic Study on Leaching of Colemanite in Ammonium Nitrate Solutions

The dissolution of colemanite in aqueous ammonium nitrate solutions was investigated in a batch reactor in terms of stirring speed, particle size, reaction temperature, solid-to-liquid ratio and solution concentration. The results showed that the dissolution rate increased with increasing temperature and concentration of ammonium nitrate solution as well as decreasing particle size and solid-to-liquid ratio, while no important effect of stirring speed was observed on dissolution rate. Colemanite could be dissolved up to 100 percent in aqueous ammonium nitrate solutions. The dissolution kinetics of colemanite was examined according to heterogeneous and homogeneous reaction models. The experimental data revealed high activation energy, indicating that the dissolution rate based on heterogeneous reaction models can be expressed as 1-(1-X)^1/3=3.28 ×10⁴·D^{-0.653 7}·C^{1.295 8}·(S/L)^{-0.490 9}·e^-41.40/(RT)·t. The activation energy of the process was found to be 41.40 kJ·mol^-1.