Abstract To explore the high value of aluminum ash development and utilization, factors (granularity of aluminum ash, leaching temperature, leaching time, sulfuric acid concentration, and liquid solid ratio) affecting the leaching rate of aluminum were evaluated. The kinetics of the leaching process was also investigated. The results indicate that the leaching rate of aluminum in aluminum ash can reach 88.9% under the following conditions: leaching temperature, 100 °C; leaching time, 120 min; sulfuric acid concentration, 2.5 mol/L; and liquid–solid ratio (mass ratio), 1.3:1. Studies on the leaching dynamics of aluminum in aluminum ash showed that leaching was divided into two stages. At the initial stage (i.e. at the leaching rate x ≤ 0.3), the external diffusion resistance and the diffusion resistance of the solid product layer are negligible, and leaching is controlled by chemical reaction at the interface. The apparent activation energy was 5733.25 J/mol. At the leaching rate x = 0.3–0.9, the leaching rate was controlled by the non-steady diffusion of the liquid film in the porous solid by the fluid reactant H2SO4. The apparent activation energy was 25390.87 J/mol. Graphical Abstract

中文翻译：

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硫酸浸出铝灰中铝的动力学研究

摘要 为探索铝灰开发利用的高价值，对影响铝浸出率的因素（铝灰粒度、浸出温度、浸出时间、硫酸浓度、液固比）进行了评价。还研究了浸出过程的动力学。结果表明，在下列条件下，铝灰中铝的浸出率可达88.9%：浸出温度100℃；浸出时间，120分钟；硫酸浓度，2.5 mol/L；和液固比（质量比），1.3:1。对铝灰中铝浸出动力学的研究表明，浸出分为两个阶段。在初始阶段（即浸出率x≤0.3），固体产物层的外扩散阻力和扩散阻力可以忽略不计，浸出由界面处的化学反应控制。表观活化能为5733.25 J/mol。在浸出速率 x = 0.3-0.9 时，浸出速率由流体反应物 H2SO4 在多孔固体中的液膜非稳态扩散控制。表观活化能为25390.87 J/mol。图形概要