The effectiveness and efficiency of the reactive extraction technique for recovery of propionic acid and malic acid from aqueous solution were investigated. Kinetic studies for the solute (acid)–solvent (trioctylamine dissolved in 1-decanol) system were carried out and mass transfer coefficients experimentally determined. These parameters are necessary for the proper design of an extraction unit. The studies were carried out using dilute solutions of the acids with a concentration range of 0.2–0.6 kmol/m³ and trioctylamine (10%v/v) in 1-decanol as extractant at 303.15 K. The effect of stirring speed, acid and extractant concentration at different time intervals was studied. The kinetic process parameters such as reaction order, mass transfer coefficient and rate constant were evaluated using the experimental data. From the results obtained, the reaction was found to be an instantaneous second-order chemical reaction occurring in the organic diffusion film. The values of the rate constants were found to be 0.430 m³/mol s and 0.332 m³/mol s, respectively, for propionic acid and malic acid, while the mass transfer coefficient, k_m, was also obtained for propionic acid (9 × 10⁻⁶ m/s) and malic acid (3 × 10⁻⁶ m/s). These are useful for the design of an extraction unit for carboxylic acid recovery from dilute aqueous solutions.

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三辛胺在1-癸醇中丙酸和苹果酸反应性萃取的动力学研究

研究了反应萃取技术从水溶液中回收丙酸和苹果酸的有效性和效率。进行了溶质（酸）-溶剂（溶于1-癸醇的三辛胺）系统的动力学研究，并通过实验确定了传质系数。这些参数对于提取单元的正确设计是必需的。使用浓度范围为0.2–0.6 kmol / m ³的酸的稀溶液进行研究。在303.15 K下于1-癸醇中以三辛胺（10％v / v）作为萃取剂。研究了搅拌速度，酸和萃取剂浓度在不同时间间隔的影响。使用实验数据评估动力学过程参数，例如反应顺序，传质系数和速率常数。根据获得的结果，发现该反应是在有机扩散膜中发生的瞬时二级化学反应。发现丙酸和苹果酸的速率常数分别为0.430 m ³ / mol s和0.332 m ³ / mol s，而丙酸的传质系数k _m也为（9 ×10 ^-6  m / s）和苹果酸（3×10 ^-6 多发性硬化症）。这些对于设计用于从稀水溶液中回收羧酸的萃取单元是有用的。