304 research outputs found

    novel geopolymeric material cured at room temperature

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    [EN] Alkali activated binders are a new class of binding material with comparable or enhanced performance to Portland cement. These binding materials are obtained by a chemical reaction between an aluminosilicate material and a highly alkaline solution. In most cases, the setting hardening process of this binder is performed at high curing temperatures. In this paper, alkali activated mortars based on vitreous calcium aluminosilicate (VCAS) cured at room temperature are evaluated. Mechanical strength development and microstructural analysis (scanning electron microscopy, thermogravimetric analysis, X-ray diffraction and mercury intrusion porosimetry) of these materials are performed. Mortars yielded compressive strength ¡-89 MPa after 360 days. This is the first time that VCAS is used as aluminosilicate source material in the production of alkali activated mortars cured at room temperature.The authors acknowledge the Ministerio de Ciencia e Innovacio´ n of the Spanish Government (projecto. BIA2011-26947) and the Vitrominerals company for supplying VCAS samples.Mitsuuchi Tashima, M.; Soriano Martínez, L.; Monzó Balbuena, JM.; Borrachero Rosado, MV.; Paya Bernabeu, JJ. (2013). novel geopolymeric material cured at room temperature. Advances in Applied Ceramics. 112:179-183. https://doi.org/10.1179/1743676112Y.0000000056S17918311

    Refluxed rice husk ash/NaOH suspension for preparing alkali activated binders

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    Geopolymers simultaneously containing two waste materials have been developed: fluid catalytic cracking catalyst (FCC) as mineral admixture and rice husk ash (RHA) for preparing an alkaline activator. Alkaline activators were prepared by refluxing aqueous mixtures of ground or original RHA with NaOH. All mortars with alkaline activator containing RHA show compressive strength (cured at 65 °C for 1 day) in the range of 31 41 MPa, which is similar to control mortar prepared using an equivalent mixture of NaOH and water glass. Refluxing times between 30 and 240 min yielded good performance mortars. This new way of valorisation would imply economic and environmental benefits in geopolymer production.GEOCEDEM Project BIA 2011-26947 was financed by Spanish Government, Project 3018/2009 was financed by Generalitat Valenciana, Project AP/35235/11 was financed by AECID, COMBURES Project was financed by Centro de Cooperacion al Desarrollo de la Universitat Politecnica de Valencia ADSIDEO COOPERACIO and OMYA Clariana S.A. and Maicerias Espanolas DACSA S.A. supplied FCC and RHA samples respectively.Bouzón, N.; Paya Bernabeu, JJ.; Borrachero Rosado, MV.; Soriano Martínez, L.; Mitsuuchi Tashima, M.; Monzó Balbuena, JM. (2014). Refluxed rice husk ash/NaOH suspension for preparing alkali activated binders. Materials Letters. 115:72-74. https://doi.org/10.1016/j.matlet.2013.10.001S727411

    ING116070: a study of the pharmacokinetics and antiviral activity of dolutegravir in cerebrospinal fluid in HIV-1-infected, antiretroviral therapy-naive subjects.

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    BackgroundDolutegravir (DTG), a once-daily, human immunodeficiency virus type 1 (HIV-1) integrase inhibitor, was evaluated for distribution and antiviral activity in cerebrospinal fluid (CSF).MethodsING116070 is an ongoing, single-arm, open-label, multicenter study in antiretroviral therapy-naive, HIV-1-infected adults. Subjects received DTG (50 mg) plus abacavir/lamivudine (600/300 mg) once daily. The CSF and plasma (total and unbound) DTG concentrations were measured at weeks 2 and 16. The HIV-1 RNA levels were measured in CSF at baseline and weeks 2 and 16 and in plasma at baseline and weeks 2, 4, 8, 12, and 16.ResultsThirteen white men enrolled in the study; 2 withdrew prematurely, 1 because of a non-drug-related serious adverse event (pharyngitis) and 1 because of lack of treatment efficacy. The median DTG concentrations in CSF were 18 ng/mL (range, 4-23 ng/mL) at week 2 and 13 ng/mL (4-18 ng/mL) at week 16. Ratios of DTG CSF to total plasma concentration were similar to the unbound fraction of DTG in plasma. Median changes from baseline in CSF (n = 11) and plasma (n = 12) HIV-1 RNA were -3.42 and -3.04 log10 copies/mL, respectively. Nine of 11 subjects (82%) had plasma and CSF HIV-1 RNA levels <50 copies/mL and 10 of 11 (91%) had CSF HIV-1 RNA levels <2 copies/mL at week 16.ConclusionsThe DTG concentrations in CSF were similar to unbound plasma concentrations and exceeded the in vitro 50% inhibitory concentration for wild-type HIV (0.2 ng/mL), suggesting that DTG achieves therapeutic concentrations in the central nervous system. The HIV-1 RNA reductions were similar in CSF and plasma. Clinical Trials Registration. NCT01499199

    The sensory acceptability of a tilapia (Oreochromis niloticus) mechanically separated meat-based spread.

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    A carne mecanicamente separada (CMS) é uma alternativa para a diversificação de novos produtos à base de pescado e também se mostra como um destino para os resíduos da indústria de filetagem. A carne mecanicamente separada de tilápia foi utilizada, neste estudo, na formulação de patê, com o objetivo de investigar a aceitabilidade desse produto pelos consumidores. Duas formulações de patê foram preparadas, com diferentes tipos de sais comerciais: sal temperado (A) e sal comum (B). Consumidores (112) avaliaram a aceitação em relação à impressão global, à espalhabilidade, à aparência e ao sabor em escala hedônica de nove pontos. A análise microbiológica da carne mecanicamente separada de tilápia e a composição química da formulação de patê de tilápia também foram determinadas. Quando a aceitação de todos os consumidores foi considerada, a impressão global, a aparência e o sabor foram significativamente (p < 0,05) inferiores para o patê de tilápia com sal comum (B). No entanto, três diferentes grupos de consumidores foram encontrados a partir da aceitabilidade da impressão global do patê de tilápia. O maior segmento também preferiu o patê de tilápia com sal temperado (A), mas ambos tiveram alta aceitabilidade. A CMS de tilápia apresentou qualidade como matéria-prima de acordo com regulamento técnico sobre padrões microbiológicos. O produto final apresentou a seguinte composição química: umidade - 62,17%; cinzas - 2,11%; proteína - 9,75%, e lipídios - 18,81%. Esses resultados podem ser de grande importância para a indústria no desenvolvimento e na comercialização de novos produtos obtidos a partir da carne mecanicamente separada de tilápia

    Behavior of metakaolin-based geopolymers incorporating sewage sludge ash (SSA)

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    [EN] In recent years, geopolymers have become a widely researched binding material. There are technological and environmental advantages tousing this type of binder instead of Portland cement. In this study, binary systems of geopolymers were produced by using mixtures of metakaolin (MK) ,a well-known aluminosilicate raw material, and a residue from sewage sludge incineration: sewage sludge ash (SSA). This ash was used to partially replace the metakaolin in proportions of 0 20%. The mixtures were activated with alkaline solutions and they were cured by using two different conditions: at room temperature (25 °C) and in a thermal bath (65 °C). The samples were assessed by X-ray diffraction, scanning electron microscopy (pastes) and compressive strength (mortars). The results from these studies showed zeolite formation (faujasite) in geopolymers cured in the thermal bath, which caused a decrease in the compressive strength of the alkali-activated mortars.Replacement of MK with SSA caused a lower reduction in the compressive strength of mortars cured at 65 °C. However, at room temperature, similar mechanical strength was observed for the MK and MK-SSA systems. These results demonstrated that SSA is a suitable mineral precursor for partial replacement of MK in geopolymer production.The authors acknowledge Santander Universidades for the grant to Lucia Reig (program: Becas lberoamerica Jovenes Profesores Investigadores Espana 2014), CAPES (CAPES/DGU no 266/12), CNPq (no. 14/2013 processo 478057/2013-0) Scanning electron microscopy service of FEIS/UNESP and CNPq (processo 309015/2015-4).Istuque, D.; Reig Cerdá, L.; Moraes, J.; Akasaki, JL.; Borrachero Rosado, MV.; Soriano Martínez, L.; Paya Bernabeu, JJ.... (2016). Behavior of metakaolin-based geopolymers incorporating sewage sludge ash (SSA). Materials Letters. 180:192-195. https://doi.org/10.1016/j.matlet.2016.05.137S19219518

    Alkali activated materials based on fluid catalytic cracking catalyst residue (FCC): Influence ofSiO2/Na2O and H2O/FCC ratio on mechanical strength and microstructure

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    Reuse of industrial and agricultural wastes as supplementary cementitious materials (SCMs) in concrete and mortar productions contribute to sustainable development. In this context, fluid catalytic cracking catalyst residue (spent FCC), a byproduct from the petroleum industry and petrol refineries, have been studied as SCM in blended Portland cement in the last years. Nevertheless, another environmental friendly alternative has been conducted in order to produce alternative binders with low CO2 emissions. The use of aluminosilicate materials in the production of alkali-activated materials (AAMs) is an on going research topic which can present low CO2 emissions associated. Hence, this paper studies some variables that can influence the production of AAM based on spent FCC. Specifically, the influence of SiO2/Na2O molar ratio and the H2O/spent FCC mass ratio on the mechanical strength and microstructure are assessed. Some instrumental techniques, such as SEM, XRD, pH and electrical conductivity measurements, and MIP are performed in order to assess the microstructure of formed alkali-activated binder. Alkali activated mortars with compressive strength up to 80 MPa can be formed after curing for 3 days at 65 C. The research demonstrates the potential of spent FCC to produce alkali-activated cements and the importance of SiO2/Na2O molar ratio and the H2O/spent FCC mass ratio in optimising properties and microstructure.Authors would like to thank to the Ministerio de Ciencia e Innovacion (MICINN) of the Spanish Government (BIA2011-26947) and to FEDER for funding, and also to the PROPG - UNESP "Universidade Estadual Paulista Julio de Mesquita Filho'', Brazil.Mitsuuchi Tashima, M.; Akasaki, JL.; Melges, J.; Soriano Martínez, L.; Monzó Balbuena, JM.; Paya Bernabeu, JJ.; Borrachero Rosado, MV. (2013). Alkali activated materials based on fluid catalytic cracking catalyst residue (FCC): Influence ofSiO2/Na2O and H2O/FCC ratio on mechanical strength and microstructure. Fuel. 108:833-839. https://doi.org/10.1016/j.fuel.2013.02.052S83383910

    Evaluation of the long-term compressive strength development of the sewage sludge ash/metakaolin-based geopolymer

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    [EN] This paper aimed to evaluate the long-term compressive strength development of the sewage sludge ash/metakaolin (SSA/MK)¿based geopolymer. SSA/MK¿based geopolymeric mortars and pastes were produced at 25ºC with different SSA contents (0 - 30 wt.%). Compressive strength tests were run within the 3-720 curing days range. A physicochemical characterisation (X-ray diffraction and scanning electron microscopy) was performed in geopolymeric pastes. All the geopolymeric mortars presented a compressive strength gain with curing time. The mortars with all the SSA evaluated contents (10, 20, 30 wt.%) developed a compressive strength over 40 MPa after 720 curing days at 25ºC. The maximum compressive strength of the mortars with SSA was approximately 61 MPa (10 wt.% of SSA), similarly to the reference mortar (100% MK-based geopolymer). The microstructure analyses showed that the SSA/MK¿based geopolymer presented a dense microstructure with N-A-S-H gel formation.This study was financed partly by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Su-perior -Brasil (CAPES) -(Finance Code 001 and CAPES/DGU n. 266/12), and the National Council of Scientific and Technological Development -Bra-sil (CNPq) -(n. 14/2013, process 478057/2013-0 and 309015/2015-4). The authors would like to thank Programa Institucional de Internacionalizacao - CAPES -PrInt. The authors acknowledge the Scanning Electron Microscopy Service of FEIS/UN-ESP, Servico Municipal Autonomo de Agua e Es-goto (SEMAE) from the Sao Jose do Rio Preto city -SP, Brazil and Diatom Mineracao Ltda. The authors would like to thank Programa Institucional de Internacionalizacao CAPES -PrInt.Istuque, D.; Soriano Martinez, L.; Borrachero Rosado, MV.; Paya Bernabeu, JJ.; Akasaki, JL.; Melges, JLP.; Tashima, MM. (2021). Evaluation of the long-term compressive strength development of the sewage sludge ash/metakaolin-based geopolymer. Materiales de Construcción. 71(343):1-10. https://doi.org/10.3989/mc.2021.13220S1107134

    Valorization of sugarcane bagasse ash (SCBA) with high quartz content as pozzolanic material in portland cement mixtures

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    [EN] Portland cement (OPC) production is one of the most contaminating greenhouse gas producing activities. In order to reduce OPC consumption, several alternatives are being assessed, and the use of pozzolanic material is one of them. This paper presents study on the reactivity of sugarcane bagasse ash (SCBA), a residue from sugarcane industry, as a pozzolanic material. In order to evaluate SCBA reactivity, it was mixed in pastes with hydrated lime and OPC, which were microstructurally characterised. These studies showed that SCBA presents some pozzolanic characteristics. Studies on mortars in which OPC was replaced by SCBA in the range 10¿30% were also carried out. Replacement in the range 15¿20% yielded the best behaviour in terms of compressive strength. Finally, it can be concluded this ash could be valorised despite its relative low pozzolanic reactivity.[ES] Valorización de la ceniza de bagazo de azúcar (SCBA) con alto contenido de cuarzo como material puzolánico en mezclas de cemento Portland. La producción de cemento Portland (OPC) presenta una elevada emisión de CO2. Con el objeto de reducir el consumo de OPC, se están evaluando algunas alternativas, y el uso de materiales puzolánicos es una de ellas. En este trabajo se presenta el estudio de la reactividad de la ceniza de bagazo de caña de azúcar (SCBA) como material puzolánico, un residuo procedente de la industria de la caña de azúcar. Al objeto de evaluar la reactividad de SCBA, se realizaron pastas con cal hidratada y con OPC, las cuales fueron caracterizadas microestructuralmente. Estos estudios mostraron que SCBA presenta una cierta característica puzolánica. Se llevaron a cabo estudios en morteros en los que OPC se sustituyó por SCBA en el intervalo de 10-30%. La sustitución en el intervalo 15-20% produjo el mejor comportamiento en términos de resistencia a compresión. Finalmente, se puede concluir que esta ceniza puede ser valorizada a pesar de su baja reactividad puzolánica.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), CNPq (Project 401724/2013-1) and Electron Microscopy Service of the Universitat Politecnica de Valencia.Pereira, A.; Moraes, J.; Bassan De Moraes, M.; Akasaki, J.; Tashima, M.; Soriano Martinez, L.; Monzó Balbuena, JM.... (2018). Valorization of sugarcane bagasse ash (SCBA) with high quartz content as pozzolanic material in portland cement mixtures. Materiales de Construcción. 68(330):153-163. https://doi.org/10.3989/mc.2018.00617S153163683301. World cement production. CEMBUREAU – The European Cement Association Website; https://cembureau.eu/media/1503/2015activityreport_cembureau.pdf2. Guo, X.; Shi, H.; Dick, W.A. (2010) Compressive strength and microstructural characteristics of class C fly ash geopolymer. Cem. Concr. Compos. 32, 142–7.3. Mehta, P.K.; Monteiro, P.J.M. Concrete: Microstructure, Properties, and Materials. 3rd ed. New York: McGraw- Hill, (2006).4. Mo, K.H.; Alengaram, U.J.; Jumaat, M.Z. (2016) Structural performance of reinforced geopolymer concrete members: A review, Constr. Build. Mater. 120, 251-264.5. Sharp, J.H.; Gartner, E.M.; Macphee, D.E. (2010) Novel cement system (sustainability). Session 2 of the Fred Glasser cement science symposium. Adv. Cem. Res. 22(4), 195–202.6. BS EN 197-1. Cement – Part 1: Composition, specifications and conformity criteria for common cements. London: European Committee For Standardisation; (2011).7. Siddique, R.; Khan, M.I. Supplementary Cementing Materials. 1st ed. Berlin: Springer, (2011).8. Siddique, R. Waste Material and By-Products in Concrete. 1st ed. Berlin: Springer, (2008).9. Küçükyıldırım, E.; Uzal, B. (2014) Characteristics of calcined natural zeolites for use in high-performance pozzolan blended cements. Constr. Build. Mater. 73, 229–34.10. Tashima, M.M.; Soriano, L.; Monzó, J.; Borrachero, M.V.; Akasaki, J.L.; Payá, J. (2014) New method to assessthe pozzolanic reactivity of mineral admixtures by means pH and electrical conductivity measurementsin lime:pozzolan suspensions. Mater. Construc. 64 [316], e032.11. Wongkeo, W.; Thongsanitgarn, P.; Chaipanich, A. (2012) Compressive strength and drying shrinkage of fly ash-bottom ash-silica fume multi-blended cement mortars. Mater. Des. 36, 655-62.12. Lee, C.L.; Huang, R.; Lin, W.T.; Weng, T.L. (2012) Establishment of the durability indices for cement-based composite containing supplementary cementitious materials. Mater. Des. 37, 28-39.13. Sinsiri, T.; Kroenhong, W.; Jaturapitakkul, C.; Chindaprasirt, P. (2012) Assessing the effect of biomass ashes with different finenesses on the compressive strength of blended cement paste. Mater. Des. 42, 424-33.14. Pereira, C.L.; Savastano Jr., H.; Payá, J.; Santos, S.F.; Borrachero, M.V.; Monzó, J. (2013) Use of highly reactive rice husk ash in the production of cement matrix reinforced with green coconut fiber. Ind. Crop. Prod. 49, 88–96.15. Paiva, H.; Velosa, A.; Cachim, P.; Ferreira, V.M. (2016) Effect of pozzolans with diferent physical and chemical characteristics on concrete properties. Mater. Construc. 66 [322], 1-12. 516. Hoi, L.W.S.; Martincigh, B.S. (2013) Sugar cane plant fibres: Separation and characterization. Ind. Crop. Prod. 47, 1–12.17. Hugot, E. Handbook of Cane Sugar Engineering. 3rd ed. Amsterdam:Elsevier Science Publishers, (1986).18. Sugarcane production. FAOSTAT – Food and Agriculture Organisation of the United Nations, Statistics Division; http://www.fao.org/faostat/en/#data/QC19. Sugarcane production. UNICA – União da Indústria de Cana-de-Açúcar Website; http://www.unicadata.com. br/index.php?idioma=220. A Geração Termoelétrica com a Queima do Bagaço de Cana-de-Açúcar no Brasil. CONAB – Companhia Nacional de Abastecimento; http://www.agricultura.gov.br/assuntos/sustentabilidade/agroenergia/arquivos-termoeletrica-com-a-queima-do-bagaco-de-cana-de-acucar/termoeletrica-com-a-queima-do-bagaco-de-cana-de-acucar-no-brasil-safra-2009-2010.pdf21. Cortez, L.A.B.; Gómez, E.O. (1998) A method for exergy analysis of sugarcane bagasse boilers. Braz. J. Chem. Eng. 15 [1].22. Souza, A.E.; Teixeira, S.R.; Santos, G.T.A.; Costa, F.B.; Longo, E. (2011) Reuse of sugarcane bagasse ash (SCBA) to produce ceramic materials. J. Environ. Manage. 92, 2774–80.23. Hofsetz, K.; Silva, M.A. (2012) Brazilian sugarcane bagasse: Energy and non-energy consumption. Biomass Bioenerg 46, 564–573.24. Cordeiro, G.C.; Toledo Filho, R.D.; Tavares, L.M.; Fairbairn, E.M.R. (2009) Ultrafine grinding of sugar cane bagasse ash for application as pozzolanic admixture in concrete. Cem. Concr. Res. 39, 110–115.25. Frías, M.; Villar, E.; Savastano, H. (2011) Brazilian sugar cane bagasse ashes from the cogeneration industry as active pozzolans for cement manufacture. Cem. Concr. Compos. 33, 490–496.26. Fairbairn, E.M.R.; Americano, B.B.; Cordeiro, G.C.; Paula, T.P.; Toledo Filho, R.D.; Silvoso, M.M. (2010) Cement replacement by sugar cane bagasse ash: CO2 emissions reduction and potential for carbon credits. J. Environ. Manage. 91, 1864–1871.27. Cordeiro, G.C.; Toledo Filho, R.D.; Fairbairn, E.M.R. (2009) Effect of calcination temperature on the pozzolanic activity of sugar cane bagasse ash. Constr. Build. Mater. 23, 3301–3303.27. UNE-EN 196-5. Método de ensayo de cementos. Parte 5: Ensayo de puzolanicidad para los cementos puzolánicos. Madrid: Asociación Espa-ola de Normalización y Certificación – AENOR; (2011).29. NBR 7215. Cimento Portland – Determinação da resistência à compressão. Rio de Janeiro: Associação Brasileira de Normas Técnicas – ANBT; (1996).29. ASTM C-618. Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete. Philadelphia: ASTM International; (2005).31. Allahverdi, A.; Shaverdi, B.; Kani, E. (2010) Influence of sodium oxide on properties of fresh and hardened paste of alkali-activated blast-furnace slag. Int. J. Civ. Eng. 8, 304–314.32. Yu, P.; Kirkpatrick, R.J.; Poe, B.; McMillan, P.F.; Cong, X. (1999) Structure of calcium silicate hydrate (C-S-H): Near-, mid-, and far-infrared spectroscopy. J. Am. Ceram. Soc. 82(3), 742–748.33. Moraes, J.C.B.; Akasaki, J.L.; Melges, J.L.P.; Monzó, J.; Borrachero, M.V.; Soriano, L.; Payá, J.; Tashima, M.M. (2015) Assessment of sugar cane straw ash (SCSA) as pozzolanic material in blended Portland cement: Microstructural characterisation of pastes and mechanical strength of mortars. Constr. Build. 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    Use of residual diatomaceous earth as a silica source in geopolymer production

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    [EN] The use of binders as an alternative to Portland cement has gained importance in recent years. Among them, geopolymeric binders, developed by the reaction between an aluminosilicate precursor and a high alkalinity solution, have become one of the most promising alternatives. The activating solution generally comprises waterglass and sodium hydroxide. Since waterglass is the most expensive material and has a high environmental impact, using alternative silica sources will lead to more sustainable binders. Previous studies have successfully used rice husk ash (RHA) as a silica source. This research aims to assess the possibility of using diatomaceous earth (or diatomite) as an alternative silica source, like the previous studies with RHA. Diatomite is a sedimentary rock with a high amorphous silica content formed by fossilized diatom remains. In this work, the geopolymer was obtained using a fluid cracking catalyst residue as the precursor and six different activating solution types prepared with commercial products, residual diatomite (from beer and wine industries) and RHA. The results open a new possible route for the reuse and recovery of diatomaceous earth residue, although the compressive strength results of the mortars were slightly lower than those for mortars prepared with RHA or commercial reagents.This work has been financially supported by the Spanish education, culture and sport ministry through the project BIA 2015-70107-R. Thanks are given to Heineken, Bodegas Vicente Gandia, OMYA, Dacsa and JJ Minerals for providing the materials.Font-Pérez, A.; Soriano Martinez, L.; Reig, L.; Tashima, M.; Borrachero Rosado, MV.; Monzó Balbuena, JM.; Paya Bernabeu, JJ. (2018). Use of residual diatomaceous earth as a silica source in geopolymer production. Materials Letters. 223:10-13. https://doi.org/10.1016/j.matlet.2018.04.010S101322

    A new geopolymeric binder from hydrated-carbonated cement

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    This paper evaluates the use of hydrated Portland cement as the raw material in the production of geopolymers. The silicon and aluminium oxides needed for the geopolymerization process were produced by the carbonation of hydrated Portland cement, which transforms CSH and CAH (Portland cement hydrates) into silica and alumina gels. Hydrated-carbonated Portland cement was alkali activated with a NaOH/waterglass solution. Pastes and mortars were prepared, and micro-structural and mechanical properties were analyzed. It has been noted that geopolymers are mechanically stable and yield compressive strength higher than 10 MPa when mortars are cured at 65 °C for 3 days. The results have shown that there are interesting possibilities for re-using the cement-rich fraction of construction and demolition waste. Alkaline activation of hydrated-carbonated Portland cement could be considered a low CO 2-emission binder. © 2012 Elsevier B.V. All rights reserved.Paya Bernabeu, JJ.; Borrachero Rosado, MV.; Monzó Balbuena, JM.; Soriano Martinez, L.; Mitsuuchi Tashima, M. (2012). A new geopolymeric binder from hydrated-carbonated cement. Materials Letters. 74:223-225. doi:10.1016/j.matlet.2012.01.132S2232257
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