SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2020, Vol. 28 ›› Issue (11): 2758-2770.DOI: 10.1016/j.cjche.2020.07.029

• Separation Science and Engineering • 上一篇    下一篇

Adsorption equilibrium and kinetics studies of divalent manganese from phosphoric acid solution by using cationic exchange resin

Haibo Zhuang, Yanjun Zhong, Lin Yang   

  1. School of Chemical Engineering, Sichuan University, Chengdu 610065, China
  • 收稿日期:2019-12-12 修回日期:2020-07-02 出版日期:2020-11-28 发布日期:2020-12-31
  • 通讯作者: Lin Yang

Adsorption equilibrium and kinetics studies of divalent manganese from phosphoric acid solution by using cationic exchange resin

Haibo Zhuang, Yanjun Zhong, Lin Yang   

  1. School of Chemical Engineering, Sichuan University, Chengdu 610065, China
  • Received:2019-12-12 Revised:2020-07-02 Online:2020-11-28 Published:2020-12-31
  • Contact: Lin Yang

摘要: There are numerous impurities in wet-process phosphoric acid, among which manganese is one of detrimental metallic impurities, and it causes striking negative effects on the industrial phosphoric acid production and downstream commodity. This article investigated the adsorption behavior of manganese from phosphoric acid employing Sinco-430 cationic ion-exchange resin. Resorting FT-IR and XPS characterizations, the adsorption mechanism was proved to be that manganese was combined with sulfonic acid group. Several crucial parameters such as temperature, phosphoric acid content and resin dose were studied to optimize adsorption efficiency. Through optimization, removal percentage and sorption capacity of manganese reached 53.12 wt%, 28.34 mg·g-1, respectively. Pseudo-2nd-order kinetic model simulated kinetics data best and the activation energy was evaluated as 6.34 kJ·mol-1 for the sorption reaction of manganese. In addition, the global adsorption rate was first controlled by film diffusion process and second determined by pore diffusion process. It was found that the resin could adsorb up to 50.24 mg·g-1 for manganese. Equilibrium studies showed that Toth adsorption isotherm model fitted best, followed by Temkin and Langmuir adsorption isotherm models. Thermodynamic analysis showed that manganese adsorption was an endothermic process with enhanced randomness and spontaneity.

关键词: Manganese, Ion exchange, Phosphoric acid, Kinetics, Isotherm, Thermodynamics

Abstract: There are numerous impurities in wet-process phosphoric acid, among which manganese is one of detrimental metallic impurities, and it causes striking negative effects on the industrial phosphoric acid production and downstream commodity. This article investigated the adsorption behavior of manganese from phosphoric acid employing Sinco-430 cationic ion-exchange resin. Resorting FT-IR and XPS characterizations, the adsorption mechanism was proved to be that manganese was combined with sulfonic acid group. Several crucial parameters such as temperature, phosphoric acid content and resin dose were studied to optimize adsorption efficiency. Through optimization, removal percentage and sorption capacity of manganese reached 53.12 wt%, 28.34 mg·g-1, respectively. Pseudo-2nd-order kinetic model simulated kinetics data best and the activation energy was evaluated as 6.34 kJ·mol-1 for the sorption reaction of manganese. In addition, the global adsorption rate was first controlled by film diffusion process and second determined by pore diffusion process. It was found that the resin could adsorb up to 50.24 mg·g-1 for manganese. Equilibrium studies showed that Toth adsorption isotherm model fitted best, followed by Temkin and Langmuir adsorption isotherm models. Thermodynamic analysis showed that manganese adsorption was an endothermic process with enhanced randomness and spontaneity.

Key words: Manganese, Ion exchange, Phosphoric acid, Kinetics, Isotherm, Thermodynamics