New geopolymeric binder based on fluid catalytic cracking catalyst residue (FCC)

This paper provides information about the synthesis and mechanical properties of geopolymers based on fluid catalytic cracking catalyst residue (FCC). FCC was alkali activated with solutions containing different SiO 2/Na 2O ratios. The microstructure and mechanical properties were analysed by using several instrumental techniques. FCC geopolymers are mechanically stable, yielding compressive strength about 68 MPa when mortars are cured at 65°C during 3 days. The results confirm the viability of producing geopolymers based on FCC. © 2012 Elsevier B.V. All rights reserved.We acknowledge the Ministerio de Ciencia e Innovacion (MICINN) of the Spanish Government and FEDER funds (MAT-2011-19934 project) and the PROPG-UNESP "Universidade Estadual Paulista Julio de Mesquita Filho", Brazil.Mitsuuchi Tashima, M.; Akasaki, JL.; Castaldelli, V.; Soriano Martínez, L.; Monzó Balbuena, JM.; Paya Bernabeu, JJ.; Borrachero Rosado, MV. (2012). New geopolymeric binder based on fluid catalytic cracking catalyst residue (FCC). Materials Letters. 80:50-52. https://doi.org/10.1016/j.matlet.2012.04.051S50528

Study of the binary system fly ash/sugarcane bagasse ash (FA/SCBA) in SiO2/K2O alkali-activated binders

Due environmental problems related to Portland cement consumption, many studies have been performed to diminish its use. One solution is the development of alkali-activated binders, which can decrease CO2 emissions and energy consumption by 70% when compared to Portland cement production. In addition, an alkali-activated binder presents mechanical properties similar to Portland cement mixtures, which turns into an interesting material in civil construction. Aluminosilicate-based materials are important raw materials to produce the alkali-activated binders. Therefore, two residues are presented as an aluminosilicate source in this study: fly ash (FA) and sugarcane bagasse ash (SCBA). Both residues were obtained from a combustion process to generate energy, the former from coal and the latter from the bagasse of the sugarcane industry. In addition, the alkaline activating solution is an important factor to achieve improved mechanical properties. In this context, this study investigated the influence of four different SiO2/K2O molar ratios (0, 0.36, 0.75 and 1.22) in the activating solution with a constant water content, and three FA/SCBA binder proportions (75/25, 50/50 and 25/75). Microstructural characterization was carried out by X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, mercury intrusion porosimetry, pH and electrical conductivity measurements to study the evolution of the reaction process. The compressive strength of mortars was assessed in order to determine the optimum SiO2/K2O molar ratio and FA/SCBA ratio. The tests showed that a SiO2/K2O molar ratio of 0.75 and FA/SCBA proportion of 75/25 provided the best mechanical properties.The authors would like to thank the Ministerio de Educacion, Cultura y Deporte of Spain (Cooperacion Interuniversitaria program with Brazil, Project PHB-2011-0016-PC), CAPES Brazil (Project CAPES/DGU No. 266/12) and CNPq (process no 401724/2013-1).Castaldelli, V.; Moraes, J.; Akasaki, JL.; Pinheiro Melges, JL.; Monzó Balbuena, JM.; Borrachero Rosado, MV.; Soriano Martínez, L.... (2016). Study of the binary system fly ash/sugarcane bagasse ash (FA/SCBA) in SiO2/K2O alkali-activated binders. Fuel. 174:307-316. https://doi.org/10.1016/j.fuel.2016.02.020S30731617

Spent FCC catalyst for preparing alkali-activated binders: an opportunity for a high-degree valorization

Spent FCC catalyst is a waste from the petrochemical industry which has excellent pozzolanic properties, containing more than 90% silica and alumina. Its similarity to metakaolin creates interesting prospects for its use in the production of alkali-activated binders. In this study, the alkali activation of this residue, spent FCC catalyst, through mixtures with alkali hydroxide and silicate solutions (both sodium and potassium) has been carried out. The alkali cation had an important role in the nature of AA-FCC pastes: some differences in the mass loss in the thermogravimetric tests and in the X-ray mineral characterization were found. No significant differences in compressive strength were observed for mortars cured for 3 days in several conditions: room temperature and 65ºC. Prepared AA-FCC mortars had a compressive strength of about 65-70 MPa. Microstructural studies showed that an amorphous, dense and compact microstructure was obtained, independent of the activating solution and curing condition.Mitsuuchi Tashima, M.; Soriano Martinez, L.; Akasaki, JL.; Castaldelli, V.; Monzó Balbuena, JM.; Paya Bernabeu, JJ.; Borrachero Rosado, MV. (2014). Spent FCC catalyst for preparing alkali-activated binders: an opportunity for a high-degree valorization. Key Engineering Materials. 600:709-716. doi:10.4028/www.scientific.net/KEM.600.709S70971660

Preliminary estudies on the use of sugar cane bagasse ash (SCBA) in the manufacture of alkali activated binders

Alkali activated binders require the addition of a mineral-rich amorphous silica and alumina. This paper proposes the use of a mineral residue from the burning of sugar cane bagasse. The alkali activated mixtures were prepared containing binary mixtures of sugar cane bagasse ash (SCBA) and other mineral admixtures: fly ash (FA) or blast furnace slag (BFS). As alkaline activators, mixtures of alkali (Na+ or K+) hydroxide and alkali (Na+ or K+) silicate were used. Alkali-activated pastes and mortars containing binary systems SCBA/FA or SCBA/BFS were prepared and cured at 65 oC. Microstructural properties of these alternative binders were assessed by means of TGA, SEM, XRD and pH measurements. Mechanical strength of mortars was performed after 3 and 7 days at 65 oC. Compressive mechanical strengths of these mortars were in the range 30-55 MPa, showing the good mechanical performance achieved by the alkali activation. Microstructural studies suggested the development of stable matrices and the formation of typical gel.Castaldelli, V.; Mitsuuchi Tashima, M.; Melges, J.; Akasaki, JL.; Monzó Balbuena, JM.; Borrachero Rosado, MV.; Soriano Martínez, L.... (2014). Preliminary estudies on the use of sugar cane bagasse ash (SCBA) in the manufacture of alkali activated binders. Key Engineering Materials. 600:689-698. doi:10.4028/www.scientific.net/KEM.600.689S689698600M.M. Tashima, C.F. Fioriti, J.L. Akasaki, J. Payá, L.C. Sousa, J.L. Pinheiro Melges. High reactive rice husk ash (RHA): production method and pozzolanic reactivity,. Ambiente Construído, 2012, 12: 151-163.L.M. Ordoñez. "Reutilización de la ceniza de cáscara de arroz como material de construcción: Valorización y optimización de sus propiedades puzolánicas (PhD Thesis). Universidad Politécnica de Valencia, (2007).J. Monzó, J. Payá, M.V. Borrachero, A. Córcoles. Use of sewage sludge ash (SSA)-cement admixtures in mortars,. Cem Concr Res 1996; 26(9): 1389-1398.M. García De Lomas, M.I. Sánchez De Rojas, M. Frías. Pozzolanic reaction of a spent fluid catalytic cracking catalyst in FCC-cement mortars,. J Therm Anal Calorim 2007, 90: 443-447.J. Payá, J. Monzó, M.V. Borrachero. Fluid catalytic cracking catalyst residue (FC3R) An excellent mineral by-product for improving early-strength development of cement mixtures,. Cem Concr Res 1999; 29: 1773-1779.F. Puertas, I. García-Díaz, A. Barba, M.F. Gazulla, M. Palacios, M.P. Gómez, S. Martínez-Ramírez. Ceramic wastes as alternative raw materials for Portland cement clinker production,. Cem Concr Comp 2008 30(9): 798-805.C. Shi, A. Fernández-Jiménez, A. Palomo. New cements for the 21st century: The pursuit of an alternative to Portland cement,. Cem Concr Res 2011; 41: 750-763.P. Duxson, A. Fernández-Jiménez, J.L. Provis, G.C. Lukey, A. Palomo, J.S.J. van Deventer. Geopolymer technology: the current state of the art,. J Mater Sci 2007; 42: 2917-2933.M. Frías, E. Villar-Cociña, E.V. Morales, H. Savastano. Study of the pozzolanic reaction kinetics in sugar cane bagasse–clay ash/calcium hydroxide system: kinetic parameters and pozzolanic activity,. Adv Cem Res 2009; 21(1): 23-30.G.C. Cordeiro, R.D. Toledo Filho, E.M.R. Fairbairn. Effect of calcination temperature on the pozzolanic activity of sugar cane bagasse ash,. Constr Build Mater 2009; 23(10): 22-28.J. Payá, J. Monzó, M.V. Borrachero, L. Díaz-Pinzón, L.M. Ordoñez. Sugar-cane bagasse ash (SCBA): studies on its properties for reusing in concrete production,. J Chem Tech Biotech 2002; 77(3): 321-325.G.C. Cordeiro, R.D. Toledo Filho, L.M. Tavares, E.M.R. Fairbairn, E.M.R. Pozzolanic activity and filler effect of sugar cane bagasse ash in Portland cement and lime mortars,. Cem Concr Comp 2008; 30(5): 410-418.J. Payá. La transmutación sostenible de los residuos para nuevas materias primas en el ámbito del concreto,. Dyna 2012; 79: 38-47

Alkali-activated binder containing wastes: a study with rice husk ash and red ceramic

In addition to several positive aspects in technical properties, geopolymeric binders have considerable advantages in the environmental point of view, with lower energy consumption and lower CO2 emission. In this study, it was conducted an overview about the utilized materials by some Brazilian researchers in geopolymers production, and also an experiment employing two types of wastes (red ceramic waste and rice husk ash). The compressive strength of the resulting material developed very fast, reaching a value of 11 MPa after one day. The microstructure was evaluated by scanning electron microscopy, revealing a compact microstructure and the presence of starting materials from the red ceramic waste that not completely reacted. The results indicated the feasibility of producing geopolymeric material without using commercial sodium silicate and cured at room temperature, showing an option for building materials production with lower environmental impacts.ISSN:0366-691