Characterization of microspheres γ-AlOOH and the excellent removal efficiency of Congo red

• Published in: The Journal of physics and chemistry of solids 2023-03, Vol.174, p.111043, Article 111043
• Main Authors: Wang, Ding, Li, Zhonglin, Lv, Fengcheng, Guan, Meijie, Chen, Junxue, Wu, Chengzhi, Li, Yuping, Li, Yibing, Zhang, Weiguang
• Format: Article
• Language: English
• Subjects: Adsorption; Congo red; Kinetics; Microspheres γ-AlOOH
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/j.jpcs.2022.111043

In this paper, Microspheres γ-AlOOH (MB) was synthesized by spray drying. Compared with commercial boehmite (CB) adsorbent, the microsphere morphology of MB is stronger than that of bulk CB in terms of thermal stability and specific surface area. The adsorption equilibrium of MB on Congo red under acidic conditions was reached within 20 min, much faster than CB. The adsorption process of MB on Congo red conformed to the pseudo-second-order and Langmuir model. The maximum adsorption capacity reached 1131.94 mg g−1, which was better than that reported in the literature. The activation energy of 21.11 kJ mol−1 and Gibbs free energy of the adsorption process of Congo red by MB were analyzed, etc. The adsorption process was determined as physical adsorption. MB has strong regeneration and adsorption capacity and has great potential for adsorbing Congo red in wastewater. [Display omitted] •Microspheres γ-AlOOH were prepared by a facile spray drying method.•It has excellent adsorption capacity for Congo red.•The adsorption mechanism has been investigated.•Determination of optimal adsorption conditions. Investigation of adsorption kinetics, activation energy and isotherms.•The negative value of the Gibbs free energy change indicates the spontaneous nature of the adsorption process.