Effective removal of Cu2+ from aqueous solution by synthetic abalone shell hydroxyapatite microspheres adsorbent

• Published in: Environmental technology & innovation 2021-08, Vol.23, Article 101663
• Main Authors: Wang, Hongbo, Yan, Kuangqi, Xing, Huaran, Chen, Jingdi, Lu, Rong
• Format: Article
• Language: English
• Subjects: Adsorption; Hydrothermal self-assembly method; Hydroxyapatite microspheres; Waste abalone shells
• ISSN: 2352-1864; 2352-1864
• DOI: 10.1016/j.eti.2021.101663

Hydroxyapatite (HA) is regarded as an excellent adsorbent because of its efficient adsorption capacity and ion exchange property. It is expected to be applied to the adsorption of heavy metals in wastewater. In this paper, HA microspheres were synthesized using waste abalone shells by simple hydrothermal self-assembly method to remove Cu2+ in wastewater. Also, several main factors which may influence the removal efficiency such as solution pH, initial Cu2+ concentration, contact time and temperature were investigated. The results showed that the adsorption capacity of abalone shell HA microspheres for Cu2+ could reach 517.1377 mg/g. Thermodynamic analysis indicated the removal of Cu2+ by HA microspheres was a spontaneous and exothermic process because of the negative values of △H0 and △G0. HA microspheres prepared from waste shells are economical and pose excellent adsorption capacities. This technology is promising for environmental protection. [Display omitted] •Converting abalone shell to Hydroxyapatite (HA) microspheres by hydrothermal method.•HA microspheres show regular spherical structures and good crystalline.•HA microspheres have excellent adsorption capacity for Cu2+.•The adsorption of Cu2+ is spontaneous with an exothermic process.