Synthesis of geopolymer from spent FCC: Effect of SiO2/Al2O
This paper assesses the feasibility of using a spent fluid catalytic cracking catalyst (SFCC) as precursor for the production of geopolymers. The mechanical and structural characterization of alkali-activated SFCC binders formulated with different overall (activator + solid precursor) SiO2/Al2O3 and...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Consejo Superior de Investigaciones Científicas
2015-03-01
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| Series: | Materiales de Construccion |
| Subjects: | |
| Online Access: | http://materconstrucc.revistas.csic.es/index.php/materconstrucc/article/view/1684 |
| Summary: | This paper assesses the feasibility of using a spent fluid catalytic cracking catalyst (SFCC) as precursor for the production of geopolymers. The mechanical and structural characterization of alkali-activated SFCC binders formulated with different overall (activator + solid precursor) SiO2/Al2O3 and Na2O/SiO2 molar ratios are reported. Formation of an aluminosilicate ‘geopolymer’ gel is observed under all conditions of activation used, along with formation of zeolites. Increased SiO2/Al2O3 induces the formation of geopolymers with reduced mechanical strength, for all the Na2O/SiO2 ratios assessed, which is associated with excess silicate species supplied by the activator. This is least significant at increased alkalinity conditions (higher Na2O/SiO2 ratios), as larger extents of reaction of the spent catalyst are achieved. SiO2/Al2O3 and Na2O/SiO2 ratios of 2.4 and 0.25, respectively, promote the highest compressive strength (67 MPa). This study elucidates the great potential of using SFCC as precursor to produce sustainable ceramic-like materials via alkali-activation. |
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| ISSN: | 0465-2746 1988-3226 |