The Effect of Activation on the Structure of Biochars Prepared from Wood and from Posidonia Oceanica: A Spectroscopic Study
The structure of two biochars and of their activated carbons was investigated by Electron Paramagnetic Resonance, Solid State Nuclear Magnetic Resonance, and Fourier Transform Infrared spectroscopies, together with X-ray diffraction and nitrogen adsorption/desorption isotherm measurements. The bioch...
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MDPI AG
2022-09-01
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| Series: | Physchem |
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| author | Silvia Pizzanelli Susanna Maisano Calogero Pinzino Antonella Manariti Vitaliano Chiodo Emanuela Pitzalis Claudia Forte |
| author_facet | Silvia Pizzanelli Susanna Maisano Calogero Pinzino Antonella Manariti Vitaliano Chiodo Emanuela Pitzalis Claudia Forte |
| author_sort | Silvia Pizzanelli |
| collection | DOAJ |
| description | The structure of two biochars and of their activated carbons was investigated by Electron Paramagnetic Resonance, Solid State Nuclear Magnetic Resonance, and Fourier Transform Infrared spectroscopies, together with X-ray diffraction and nitrogen adsorption/desorption isotherm measurements. The biochars were obtained from wood and Posidonia Oceanica by slow pyrolysis up to 600 °C, whereas the activated carbons were prepared from the biochars by impregnation with KOH, heating up to 800 °C. Two different KOH:biochar mass ratios were tested in the case of Posidonia, namely 4:1 and 2:1, while only the 4:1 ratio was used for wood. When the larger ratio was used, activation significantly increased the microporosity of the starting biochar, also creating bottle-neck pores not accessible to water molecules, and induced the formation of larger condensed aromatic networks arranged in interconnected conducting domains. In the case of Posidonia, activation using the 2:1 ratio mainly created mesopores and induced an increase in organic radical content by almost four orders of magnitude. This huge increase was related to the presence of minerals in the starting biochar. |
| first_indexed | 2024-03-09T22:48:14Z |
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| institution | Directory Open Access Journal |
| issn | 2673-7167 |
| language | English |
| last_indexed | 2024-03-09T22:48:14Z |
| publishDate | 2022-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Physchem |
| spelling | doaj.art-38ed8c4b0fb04291a9603a65faf035932023-11-23T18:25:25ZengMDPI AGPhyschem2673-71672022-09-012328630410.3390/physchem2030021The Effect of Activation on the Structure of Biochars Prepared from Wood and from Posidonia Oceanica: A Spectroscopic StudySilvia Pizzanelli0Susanna Maisano1Calogero Pinzino2Antonella Manariti3Vitaliano Chiodo4Emanuela Pitzalis5Claudia Forte6Istituto di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, ItalyIstituto di Tecnologie Avanzate per l′Energia “Nicola Giordano”, Consiglio Nazionale delle Ricerche—CNR, Via Salita S. Lucia sopra Contesse 5, 98126 Messina, ItalyIstituto di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, ItalyDipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, 56124 Pisa, ItalyIstituto di Tecnologie Avanzate per l′Energia “Nicola Giordano”, Consiglio Nazionale delle Ricerche—CNR, Via Salita S. Lucia sopra Contesse 5, 98126 Messina, ItalyIstituto di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, ItalyIstituto di Chimica dei Composti OrganoMetallici, Consiglio Nazionale delle Ricerche—CNR, Via G. Moruzzi 1, 56124 Pisa, ItalyThe structure of two biochars and of their activated carbons was investigated by Electron Paramagnetic Resonance, Solid State Nuclear Magnetic Resonance, and Fourier Transform Infrared spectroscopies, together with X-ray diffraction and nitrogen adsorption/desorption isotherm measurements. The biochars were obtained from wood and Posidonia Oceanica by slow pyrolysis up to 600 °C, whereas the activated carbons were prepared from the biochars by impregnation with KOH, heating up to 800 °C. Two different KOH:biochar mass ratios were tested in the case of Posidonia, namely 4:1 and 2:1, while only the 4:1 ratio was used for wood. When the larger ratio was used, activation significantly increased the microporosity of the starting biochar, also creating bottle-neck pores not accessible to water molecules, and induced the formation of larger condensed aromatic networks arranged in interconnected conducting domains. In the case of Posidonia, activation using the 2:1 ratio mainly created mesopores and induced an increase in organic radical content by almost four orders of magnitude. This huge increase was related to the presence of minerals in the starting biochar.https://www.mdpi.com/2673-7167/2/3/21activated carbonssolid state NMREPRFT-IRporositywater accessibility |
| spellingShingle | Silvia Pizzanelli Susanna Maisano Calogero Pinzino Antonella Manariti Vitaliano Chiodo Emanuela Pitzalis Claudia Forte The Effect of Activation on the Structure of Biochars Prepared from Wood and from Posidonia Oceanica: A Spectroscopic Study Physchem activated carbons solid state NMR EPR FT-IR porosity water accessibility |
| title | The Effect of Activation on the Structure of Biochars Prepared from Wood and from Posidonia Oceanica: A Spectroscopic Study |
| title_full | The Effect of Activation on the Structure of Biochars Prepared from Wood and from Posidonia Oceanica: A Spectroscopic Study |
| title_fullStr | The Effect of Activation on the Structure of Biochars Prepared from Wood and from Posidonia Oceanica: A Spectroscopic Study |
| title_full_unstemmed | The Effect of Activation on the Structure of Biochars Prepared from Wood and from Posidonia Oceanica: A Spectroscopic Study |
| title_short | The Effect of Activation on the Structure of Biochars Prepared from Wood and from Posidonia Oceanica: A Spectroscopic Study |
| title_sort | effect of activation on the structure of biochars prepared from wood and from posidonia oceanica a spectroscopic study |
| topic | activated carbons solid state NMR EPR FT-IR porosity water accessibility |
| url | https://www.mdpi.com/2673-7167/2/3/21 |
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