Effect of Fe(III) Modification on the Phosphorus Removal Behavior of Ce(III) Carbonate Adsorbents

Jie Yang; Zuobei Wang; Ruonan Li; Xiaofeng Xu; Junrui Liu; You-Gui Huang; Xin Ye; Wei Wang

doi:10.1021/acsomega.2c02269

Effect of Fe(III) Modification on the Phosphorus Removal Behavior of Ce(III) Carbonate Adsorbents

ACS Omega. 2022 Aug 29;7(36):31767-31777. doi: 10.1021/acsomega.2c02269. eCollection 2022 Sep 13.

Authors

Jie Yang^{1

2}, Zuobei Wang^{1

2}, Ruonan Li^{1

2}, Xiaofeng Xu^{1

2}, Junrui Liu^{1

2}, You-Gui Huang^{1

2}, Xin Ye³, Wei Wang^{1

2}

Affiliations

¹ CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China.
² Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen 361021, China.
³ Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.

Abstract

Excessive phosphorus (P) in water is the main reason for eutrophication, which has been a global problem for many years. For the adsorption treatment of phosphorus-containing wastewater, adsorbents are key research topics. In this study, we develop the synthesis of a series of Ce/Fe adsorbents by modifying the commercial cerium carbonate with Fe₂(SO₄)₃. By conducting comprehensive analysis with XRD, FTIR, and SEM, we find that the amorphous granular structure and large chunky structure created by the high and low Fe content, respectively, both had a negative effect on the adsorption capacity of phosphate. Among different adsorbents, Ce/Fe-15/3, with Ce loading of 28.33 wt % and Fe loading of 5.66 wt %, exhibits high P adsorption capacity of 58 mg P/g (in pH = 7, 30 mg P/L solution). It also demonstrates excellent selectivity toward phosphate adsorption in Cl^-, SO₄ ^2-, and NO₃ ^- solution (up to 20 times of the phosphate molarity) and good adsorption stability in acidic environments (pH = 3-6). The adsorption behavior of Ce/Fe-15/3 can be modeled well by the Langmuir model and pseudo-second-order (PSO) model. By conducting the XPS analysis, we conclude that the adsorption mechanism is a combination effect of Ce/PO₄ ^3- and Fe/PO₄ ^3- chemical interactions.