An electrochemical strategy for dredged sediment resource utilization: Phosphorus forms transformation by a neutral pH electro-Fenton system

• Published in: Journal of cleaner production Vol. 434; p. 139948
• Main Authors: Cao, Jingxiao, Wang, Ping, Zhu, Jian, Jiang, Xiaxin, Xia, Jing, Liu, Junwu, Fang, Yingchun, Cai, Jingju
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2024
• Subjects: apatite; bioavailability; Bioavailable phosphorus; Dredged sediments; Electro-Fenton; electrochemistry; Massilia; microbial communities; Microbial diversity; phosphorus; Resource utilization; sediments; sustainable development; Thiobacillus; Microbial diversity; Bioavailable phosphorus; Electro-Fenton; Resource utilization; Dredged sediments
• ISSN: 0959-6526
• DOI: 10.1016/j.jclepro.2023.139948

Dredged sediment has a high-water content and complex contaminant composition, dramatically impacting the environment if not treated and managed correctly. However, at the same time, it is also a valuable phosphorus-rich resource. Treating contaminated dredged sediments for resource recycling is critical to achieving sustainable development goals. In this study, a novelty neutral pH electro-Fenton (EF) experimental device was specifically designed for phosphorus (P) transformation study in dredged sediment. Result showed that the transformation of P forms in dredged sediments due to ·OH generation in this EF system. The decrease rates of organic P (OP) and apatite P (Ca–P) were 21.8 % and 69.6 %, respectively, while, the increase rates inorganic P (IP) and non-apatite inorganic P (Fe–P) were 25.2 % and 250.0 %, respectively, after 6 h of EF reaction. Analysis of the microbial community revealed that the EF reaction did not significantly reduce microbial diversity in the dredged sediment (p > 0.05). Furthermore, the abundance of Massilia and Thiobacillus, which are involved in transforming P form, increased significantly following the EF reaction and was positively correlated with Fe–P and IP (R2 > 0.999) and negatively correlated with OP and Ca–P (R2 > 0.999). This study proves that treating polluted dredged sediment with a neutral pH EF system can transform P into bioavailable forms. This work provides a new and sustainable strategy for recycling P from phosphorus-rich waste streams as a substitute for mining P rock. [Display omitted] •A novel electro-Fenton (EF) reactor was introduced to treat dredged sediment.•Phosphorus (P) form was converted to bioavailable P with a neutral pH EF system.•·OH mainly contributes to P conversion.•After EF, Massilia abundance, a phosphate-soluble bacterium, was increased.