Eggshell based biochar for highly efficient adsorption and recovery of phosphorus from aqueous solution: Kinetics, mechanism and potential as phosphorus fertilizer

• Published in: Bioresource technology 2022-10, Vol.362, p.127851-127851, Article 127851
• Main Authors: Sun, Chengyou, Cao, Heng, Huang, Chao, Wang, Ping, Yin, Jinglin, Liu, Hao, Tian, Haoran, Xu, Haiyin, Zhu, Jian, Liu, Zhiming
• Format: Article
• Language: English
• Subjects: Adsorbent; Eggshell modified biochar; Phosphorus recovery; Slow-release fertilizer
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2022.127851

[Display omitted] •A green biochar was prepared from eggshell and corn stalk for P adsorption.•ESBC has excellent phosphorus adsorption capacity up to 557.0 mg/g.•The feasibility of ESBC as a filter media was verified by column experiment.•ESBC exhibits good P slow-release performance and high P utilization efficiency. Development of an efficient and green adsorbent is of great significance for phosphorus removal and recovery from eutrophic water. This work prepared an eggshell modified biochar (ESBC) by co-pyrolysis of eggshells and corn stalk. ESBC exhibited an excellent performance for phosphorus adsorption over a wide pH range (5–13), and achieved a maximum adsorption of 557.0 mg P/g. The adsorption process was well fitted by pseudo-second-order model (R2 > 0.962) and Sips model (R2 > 0.965), and it was endothermic (ΔH0 > 0) and spontaneous (ΔG0