A comprehensive study of phosphorus removal and recovery with a Fe-loaded sulfoaluminate cement (FSC) adsorbent. (February 2021)

• Record Type: Journal Article
• Authors: Lian, Faqin; Gao, Shuai; Fu, Qionglin; Wu, Yuejun; Wang, Junfeng; Huang, Qing; Hu, Shan
• Is Part Of: Journal of water process engineering. Volume 39(2021)
• Publication Date: 2021-02
• Subjects: Sulfoaluminate cement -- Phosphate recycle -- Precipitation -- Adsorption; Water-supply engineering -- Periodicals; Saline water conversion -- Periodicals; Seawater -- Distillation -- Periodicals; Sanitary engineering -- Periodicals; Sewage -- Purification -- Periodicals; 627
• DOI: 10.1016/j.jwpe.2020.101744
• Languages: English
• ISSNs: 2214-7144

Abstract

Highlights: A Fe-loaded sulfoaluminate cement adsorbent was synthesized firstly for phosphorus removal. Satisfactory phosphate adsorption capacities on FSC were observed on batch and fix-bed conditions. The dominant mechanism for phosphate removal is formation of the Ca/Al-P precipitates. The adsorbed FSC can be successfully used as P-source to hydroponic Ipomoea aquatica Forsk . Abstract: The present study was designed to produce a new adsorption efficiency, cost-efficient, and recoverable cementitous adsorbent (FSC) and study the removal and recovery of phosphorus (P). The result of Langmuir isotherm revealed the maximum capacity is 46.8 mg/g. Interference by competitive ions (Cl −, NO3 −, SO4 2−, and HCO3 − ) was weak, and P adsorption reached 95% of the optimum value in a wide pH of 3.0–7.0. The results of batch experiments, SEM-EDS, XRD, and FTIR suggested that the adsorption of phosphate obviously facilitated the release of SO4 2− from the FSC hydration products via SO4 2− exchange, and formation of metal-P precipitates was the predominant P removal mechanism. The column filtration results showed the number of bed volume before P breakthrough was 1564–2112, and the effluent pH stabilized at 8.0. The P-loaded FSC was used to cultivate Ipomoea aquatica Forsk in the hydroponic boxes, the sample plant dry weight using adsorbed FSC as P-source was (0.40∼0.41) ± 0.05 g, which was dramatically increased comparing with the non-P source samples (0.19 g ± 0.07 g). Our present study firstly employed the sulfoaluminate cement-based material for eutrophic water remediation and presents a comprehensive study combining P removal mechanisms, influencing factors, and application. Insights gained from adsorption mechanisms and P recovery approach can further our understanding on the practical application of FSC.