| Title |
Effect of Activating Solution Modulus on the Synthesis of Sustainable Geopolymer Binders Using Spent Oil Bleaching Earths as Precursor |
| ID_Doc |
15771 |
| Authors |
Delgado-Plana, P; Rodríguez-Expósito, A; Bueno-Rodríguez, S; Pérez-Villarejo, L; Tobaldi, DM; Labrincha, JA; Eliche-Quesada, D |
| Title |
Effect of Activating Solution Modulus on the Synthesis of Sustainable Geopolymer Binders Using Spent Oil Bleaching Earths as Precursor |
| Year |
2021 |
| Published |
Sustainability, 13, 13 |
| DOI |
10.3390/su13137501 |
| Abstract |
The valorization of spent oil bleaching earths (SOBE) is crucial for the protection of the environment and the reuse of resources. In this research, alkali-activated binders were manufactured at room temperature using SOBE as a precursor by varying the mass ratio between the activating solutions of sodium silicate (Na2SiO3) and 6 M sodium hydroxide (NaOH) (activating solution modulus) (Na2SiO3/NaOH ratio = 1/1; 1/2; 1/3; 1/4) to investigate the influence on the technological properties of the materials. This process intends to evaluate the potential of SOBE, heat-treated at 550 degrees C (1 h), as a precursor of the reaction (source of aluminosilicates). Samples produced with higher amounts of sodium silicate developed a denser structure, with lower porosity and a higher amount of geopolymer gel. Maximum flexural (8.35 MPa) and compressive (28.4 MPa) strengths of samples cured at room temperature for 28 days were obtained with a Na2SiO3/NaOH mass ratio of 1/1. The study demonstrates that SOBE waste can be used as a precursor in the manufacture of geopolymer binders that show a good compromise between physical, mechanical and thermally insulating characteristics. |
| Author Keywords |
spent bleaching earth; geopolymers; activating solution; activator modulus; compressive strength; microstructure |
| Index Keywords |
Index Keywords |
| Document Type |
Other |
| Open Access |
Open Access |
| Source |
Science Citation Index Expanded (SCI-EXPANDED); Social Science Citation Index (SSCI) |
| EID |
WOS:000671318600001 |
| WoS Category |
Green & Sustainable Science & Technology; Environmental Sciences; Environmental Studies |
| Research Area |
Science & Technology - Other Topics; Environmental Sciences & Ecology |
| PDF |
https://www.mdpi.com/2071-1050/13/13/7501/pdf?version=1625539574
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