Composite Polysilicate Metal Coagulants for Simultaneous Removal of Organic Matter, Phosphorus, and Ammonium-Nitrogen: Effects of Metal/Silicate Molar Ratio and Basicity
Coagulation can effectively recover substances from wastewater; however, there is a lack of efficient coagulants for simultaneous recovery of organic matter, nitrogen, and phosphorus. We prepared a composite polysilicate metal (CSM) flocculant by combining Fe<sup>3+</sup> and Mg<sup&g...
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MDPI AG
2023-05-01
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| Series: | Water |
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| Online Access: | https://www.mdpi.com/2073-4441/15/9/1782 |
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| author | Hanxu Guo Peng Li Lianfeng Du Guoyuan Zou Xuan Guo |
| author_facet | Hanxu Guo Peng Li Lianfeng Du Guoyuan Zou Xuan Guo |
| author_sort | Hanxu Guo |
| collection | DOAJ |
| description | Coagulation can effectively recover substances from wastewater; however, there is a lack of efficient coagulants for simultaneous recovery of organic matter, nitrogen, and phosphorus. We prepared a composite polysilicate metal (CSM) flocculant by combining Fe<sup>3+</sup> and Mg<sup>2+</sup> ions in polysilicic acid (PSiA). According to the results of scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR), the CSM exhibited a larger amorphous phase along with new compounds, including Mg<sub>3</sub>Fe<sub>2</sub>(SiO<sub>4</sub>)<sub>3</sub> and hydroxyl metals. The CSM demonstrated a higher coagulation efficiency than PSiA and polymeric ferric sulfate, particularly for PO<sub>4</sub><sup>3−</sup>-P and NH<sub>4</sub><sup>+</sup>-N removal. The metal/silicate molar ratio substantially influenced the structure and composition of the CSM, along with the coagulation efficiency, with an optimal ratio of 3:1. Additionally, we proposed a novel preparation strategy to achieve an optimum CSM basicity (<i>B</i>*) for coagulation by adjusting the initial pH of PSiA (pH<sub>Initial</sub>) without adding an alkali agent. The results demonstrated that the optimum <i>B</i>* can be obtained by adjusting pH<sub>Initial</sub> to 0.5 or 1. The overall optimum coagulation performance for the simultaneous removal of organic matter, PO<sub>4</sub><sup>3−</sup>P, and NH<sub>4</sub><sup>+</sup>-N from wastewater was 68.5%, 99%, and 17.5%, respectively. This study provides a feasible approach for synchronous pollutant recovery from wastewater. |
| first_indexed | 2024-03-11T04:02:14Z |
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| id | doaj.art-0b0a2fae6d9a4364824fa191ed1e4962 |
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| issn | 2073-4441 |
| language | English |
| last_indexed | 2024-03-11T04:02:14Z |
| publishDate | 2023-05-01 |
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| record_format | Article |
| series | Water |
| spelling | doaj.art-0b0a2fae6d9a4364824fa191ed1e49622023-11-17T23:58:26ZengMDPI AGWater2073-44412023-05-01159178210.3390/w15091782Composite Polysilicate Metal Coagulants for Simultaneous Removal of Organic Matter, Phosphorus, and Ammonium-Nitrogen: Effects of Metal/Silicate Molar Ratio and BasicityHanxu Guo0Peng Li1Lianfeng Du2Guoyuan Zou3Xuan Guo4School of Mechanical Engineering, Tiangong University, Tianjin 300387, ChinaInstitute of Plant Nutrition, Resources and Environment, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, ChinaInstitute of Plant Nutrition, Resources and Environment, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, ChinaInstitute of Plant Nutrition, Resources and Environment, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, ChinaInstitute of Plant Nutrition, Resources and Environment, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, ChinaCoagulation can effectively recover substances from wastewater; however, there is a lack of efficient coagulants for simultaneous recovery of organic matter, nitrogen, and phosphorus. We prepared a composite polysilicate metal (CSM) flocculant by combining Fe<sup>3+</sup> and Mg<sup>2+</sup> ions in polysilicic acid (PSiA). According to the results of scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR), the CSM exhibited a larger amorphous phase along with new compounds, including Mg<sub>3</sub>Fe<sub>2</sub>(SiO<sub>4</sub>)<sub>3</sub> and hydroxyl metals. The CSM demonstrated a higher coagulation efficiency than PSiA and polymeric ferric sulfate, particularly for PO<sub>4</sub><sup>3−</sup>-P and NH<sub>4</sub><sup>+</sup>-N removal. The metal/silicate molar ratio substantially influenced the structure and composition of the CSM, along with the coagulation efficiency, with an optimal ratio of 3:1. Additionally, we proposed a novel preparation strategy to achieve an optimum CSM basicity (<i>B</i>*) for coagulation by adjusting the initial pH of PSiA (pH<sub>Initial</sub>) without adding an alkali agent. The results demonstrated that the optimum <i>B</i>* can be obtained by adjusting pH<sub>Initial</sub> to 0.5 or 1. The overall optimum coagulation performance for the simultaneous removal of organic matter, PO<sub>4</sub><sup>3−</sup>P, and NH<sub>4</sub><sup>+</sup>-N from wastewater was 68.5%, 99%, and 17.5%, respectively. This study provides a feasible approach for synchronous pollutant recovery from wastewater.https://www.mdpi.com/2073-4441/15/9/1782coagulationinorganic polymeric flocculantsammonium-nitrogen recoverybasicitydomestic wastewater treatment |
| spellingShingle | Hanxu Guo Peng Li Lianfeng Du Guoyuan Zou Xuan Guo Composite Polysilicate Metal Coagulants for Simultaneous Removal of Organic Matter, Phosphorus, and Ammonium-Nitrogen: Effects of Metal/Silicate Molar Ratio and Basicity Water coagulation inorganic polymeric flocculants ammonium-nitrogen recovery basicity domestic wastewater treatment |
| title | Composite Polysilicate Metal Coagulants for Simultaneous Removal of Organic Matter, Phosphorus, and Ammonium-Nitrogen: Effects of Metal/Silicate Molar Ratio and Basicity |
| title_full | Composite Polysilicate Metal Coagulants for Simultaneous Removal of Organic Matter, Phosphorus, and Ammonium-Nitrogen: Effects of Metal/Silicate Molar Ratio and Basicity |
| title_fullStr | Composite Polysilicate Metal Coagulants for Simultaneous Removal of Organic Matter, Phosphorus, and Ammonium-Nitrogen: Effects of Metal/Silicate Molar Ratio and Basicity |
| title_full_unstemmed | Composite Polysilicate Metal Coagulants for Simultaneous Removal of Organic Matter, Phosphorus, and Ammonium-Nitrogen: Effects of Metal/Silicate Molar Ratio and Basicity |
| title_short | Composite Polysilicate Metal Coagulants for Simultaneous Removal of Organic Matter, Phosphorus, and Ammonium-Nitrogen: Effects of Metal/Silicate Molar Ratio and Basicity |
| title_sort | composite polysilicate metal coagulants for simultaneous removal of organic matter phosphorus and ammonium nitrogen effects of metal silicate molar ratio and basicity |
| topic | coagulation inorganic polymeric flocculants ammonium-nitrogen recovery basicity domestic wastewater treatment |
| url | https://www.mdpi.com/2073-4441/15/9/1782 |
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