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Prof. José Ignacio Alvarez
Department of Chemistry, University of Navarra, Proona, Spain

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0 trace elements
0 civil engineering materials
0 calcium hydroxide
0 silica fume

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Lime-based mortars
trace elements
calcium hydroxide

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Review
Published: 05 March 2021 in Materials and Structures
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The main objective of RILEM TC LHS-277 “Specifications for testing and evaluation of lime-based repair materials for historic Structures” is the revision, adaption and, when necessary proposal, of the test methods to accurately study lime-based binding systems and mixtures, such as mortars and grouts. The empiric use of the lime-based composites and the predominant employ of cement in the field of Civil Engineering have led to the widespread application of test methods developed for cement-based composites to test the former. However, the clear differences in composition and performance between modern cement binders and lime-based materials would advise to explore specific test methods for the latter. To undertake this task the previous knowledge on the mechanisms of setting and hardening of these binders must be revised, arranged and synthesized. Processes such as drying, carbonation, hydration and pozzolanic reaction may occur during the setting and hardening of lime-based mortars and competition between them cannot be underestimated. With the aim of underpinning the revision and proposal of test methods for lime-based systems, this review paper reports a comprehensive study of the mechanisms of setting and hardening of these binders, considering the variability of the composition, which includes pure air lime as well as lime with hydraulic properties, lime-cement and lime-pozzolan systems.

ACS Style

J. I. Alvarez; R. Veiga; S. Martínez-Ramírez; M. Secco; P. Faria; P. N. Maravelaki; M. Ramesh; I. Papayianni; J. Válek. RILEM TC 277-LHS report: a review on the mechanisms of setting and hardening of lime-based binding systems. Materials and Structures 2021, 54, 1 -30.

AMA Style

J. I. Alvarez, R. Veiga, S. Martínez-Ramírez, M. Secco, P. Faria, P. N. Maravelaki, M. Ramesh, I. Papayianni, J. Válek. RILEM TC 277-LHS report: a review on the mechanisms of setting and hardening of lime-based binding systems. Materials and Structures. 2021; 54 (2):1-30.

Chicago/Turabian Style

J. I. Alvarez; R. Veiga; S. Martínez-Ramírez; M. Secco; P. Faria; P. N. Maravelaki; M. Ramesh; I. Papayianni; J. Válek. 2021. "RILEM TC 277-LHS report: a review on the mechanisms of setting and hardening of lime-based binding systems." Materials and Structures 54, no. 2: 1-30.

Journal article
Published: 23 January 2021 in Journal of Cleaner Production
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The aim of this study is to develop new air lime mortars with enhanced photocatalytic depolluting and self-cleaning abilities. Nanosilica, as pozzolanic mineral admixture, was used to improve the strength of mortars, whereas nanotitania (TiO2) was added to impart photocatalytic properties. At the same time, five different dispersing admixtures –superplasticizers– were added in bulk to the mortars to enhance the photocatalytic activity by reducing the rate of charge carrier recombination. Four polycarboxylate-based derivatives and a polynaphthalene sulfonate were tested aiming to achieve an efficient charge separation. In order to increase the lasting of the mortars subjected to water movements, sodium oleate was also added as a water repellent agent. Since the photoinduced hydrophilicity, responsible for the self-cleaning effect, might be affected by the water repellent, the compatibility between this admixture and the photocatalytic performance of the nanotitania was also investigated. Results showed that photocatalytic activity was improved due to the action of the superplasticizers as indicated by an average 33% increase of NO degradation, which is significant to the depolluting activity of these mortars. Furthermore, these mortars also showed a greatly reduced release of intermediate toxic compounds, mainly NO2: the selectivity factor (NOx/NO) reached values up to 87%. The self-cleaning ability, studied through dye degradation, of the mortars with SPs was also enhanced around 1.2 times. Three of the polycarboxylate-based superplasticizers enhanced the photosensitization of the dye under visible light irradiation, resulting in faster decolouring kinetics. In connection with the self-cleaning performance, these same SPs preserved the photoinduced hydrophilicity of the lime mortars, reaching good wettability of the surface of the mortars (water contact angles of ca. 10°), even in the presence of the sodium oleate, proving the compatible characteristics of the admixtures and allowing obtaining a new range of actively depolluting lime mortars.

ACS Style

J.F. González-Sánchez; B. Taşcı; J.M. Fernández; Í. Navarro-Blasco; J.I. Alvarez. Improvement of the depolluting and self-cleaning abilities of air lime mortars with dispersing admixtures. Journal of Cleaner Production 2021, 292, 126069 .

AMA Style

J.F. González-Sánchez, B. Taşcı, J.M. Fernández, Í. Navarro-Blasco, J.I. Alvarez. Improvement of the depolluting and self-cleaning abilities of air lime mortars with dispersing admixtures. Journal of Cleaner Production. 2021; 292 ():126069.

Chicago/Turabian Style

J.F. González-Sánchez; B. Taşcı; J.M. Fernández; Í. Navarro-Blasco; J.I. Alvarez. 2021. "Improvement of the depolluting and self-cleaning abilities of air lime mortars with dispersing admixtures." Journal of Cleaner Production 292, no. : 126069.

Journal article
Published: 16 December 2020 in Construction and Building Materials
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The present work presents focuses on the use of different admixtures for the development of rendering lime-based mortars with improved adhesion and durability, as well as reduction of cracking. To this aim, combinations of an adhesion improver (ethylene–vinyl acetate copolymer, EVA), a water repellent agent (sodium oleate), a viscosity enhancer (a starch derivative) and a mineral admixture (pozzolanic addition of nanosilica or metakaolin) were tested. The renders were applied on four different substrates (sandstone, limestone, granite and brick) to assess their performance. The influence of the admixtures’ combination on fluidity, stiffening time, adhesion, cracking, compressive strength, pore structure, frost resistance and durability against magnesium sulfate attack was evaluated. The EVA admixture was seen to enhance the adhesion when used in combination with oleate, metakaolin and starch. This combination also led to a minimized cracking. Opposite trends between adhesion and cracking were observed as a function of the porosity of the substrates and of the presence of small-sized capillary pores. The interferences with the carbonation accounted for the drops observed in compressive strength for the nanosilica-free tested renders; nanosilica-containing renders showed good compressive performance, due to the filling effect of the admixture and to the C-S-H formation. The use of most of the admixtures’ combinations was seen to clearly enhance the durability of the renders, in the face of freezing-thawing cycles as well as sulfate attack, proving the applicability of these lime-based renders for repair works of the Cultural Heritage and for new Civil Engineering applications.

ACS Style

J.F. González-Sánchez; J.M. Fernández; Í. Navarro-Blasco; J.I. Alvarez. Improving lime-based rendering mortars with admixtures. Construction and Building Materials 2020, 271, 121887 .

AMA Style

J.F. González-Sánchez, J.M. Fernández, Í. Navarro-Blasco, J.I. Alvarez. Improving lime-based rendering mortars with admixtures. Construction and Building Materials. 2020; 271 ():121887.

Chicago/Turabian Style

J.F. González-Sánchez; J.M. Fernández; Í. Navarro-Blasco; J.I. Alvarez. 2020. "Improving lime-based rendering mortars with admixtures." Construction and Building Materials 271, no. : 121887.

Editorial
Published: 31 July 2020 in International Journal of Architectural Heritage
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ACS Style

José Ignacio Álvarez. Historic Mortars and New Repair Materials for the Architectural Heritage: Selected Papers from the 5th Historic Mortars Conference (HMC 2019). International Journal of Architectural Heritage 2020, 14, 943 -947.

AMA Style

José Ignacio Álvarez. Historic Mortars and New Repair Materials for the Architectural Heritage: Selected Papers from the 5th Historic Mortars Conference (HMC 2019). International Journal of Architectural Heritage. 2020; 14 (7):943-947.

Chicago/Turabian Style

José Ignacio Álvarez. 2020. "Historic Mortars and New Repair Materials for the Architectural Heritage: Selected Papers from the 5th Historic Mortars Conference (HMC 2019)." International Journal of Architectural Heritage 14, no. 7: 943-947.

Journal article
Published: 11 April 2020 in Polymers
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This paper presents the experimental procedure to develop air lime-based injection grouts, including polymeric superplasticizers, a water repellent agent and pozzolanic agents as additives. Our research focuses on the development of grouts to improve various characteristics simultaneously by combining different additions and admixtures. Aiming to improve the injectability of the grouts, in this study, different polymeric superplasticizers were added, namely polycarboxylated-ether derivative (PCE), polynaphthalene sulfonate (PNS) and condensate of melamine-formaldehyde sulfonate (SMFC). As a water-repellent agent, sodium oleate was used to reduce the water absorption. The enhancement of the strength and setting time was intended by using microsilica and metakaolin as pozzolanic mineral additions. Compatibility between the different admixtures and action mechanism of the different polymers were studied by means of zeta potential and adsorption isotherms measurements. Diverse grout mixtures were produced and investigated by assessing their injectability, fluidity, stability, compressive strength, hydrophobicity and durability. This research led to several suitable mixtures produced by using more than one component, to enhance efficiency and to provide better performance of grouts. According to the results, the grout composed of air lime, metakaolin, sodium oleate and PCE was found to be the most effective composition, improving the mechanical strength, injectability and hydrophobicity.

ACS Style

Jesús Fidel González-Sánchez; Burcu Taşcı; José María Fernández; Íñigo Navarro-Blasco; José Ignacio Alvarez. Combination of Polymeric Superplasticizers, Water Repellents and Pozzolanic Agents to Improve Air Lime-Based Grouts for Historic Masonry Repair. Polymers 2020, 12, 887 .

AMA Style

Jesús Fidel González-Sánchez, Burcu Taşcı, José María Fernández, Íñigo Navarro-Blasco, José Ignacio Alvarez. Combination of Polymeric Superplasticizers, Water Repellents and Pozzolanic Agents to Improve Air Lime-Based Grouts for Historic Masonry Repair. Polymers. 2020; 12 (4):887.

Chicago/Turabian Style

Jesús Fidel González-Sánchez; Burcu Taşcı; José María Fernández; Íñigo Navarro-Blasco; José Ignacio Alvarez. 2020. "Combination of Polymeric Superplasticizers, Water Repellents and Pozzolanic Agents to Improve Air Lime-Based Grouts for Historic Masonry Repair." Polymers 12, no. 4: 887.

Articles
Published: 04 March 2020 in International Journal of Architectural Heritage
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Unique multifunctional coatings, comprising a 3D superhydrophobic agent and two nanostructured photocatalysts (solar-light sensitive 50/50 and 10/90 TiO2-ZnO nano-heterostructures), compatible with the inorganic substrates of the Built Heritage, have been designed. The synthesized nanoparticles showed an enhanced photocatalytic activity (tested by NO degradation) as compared with the raw TiO2 and ZnO materials. Dispersing agents were used to optimize the coatings, avoiding agglomeration of the photocatalytic nanoparticles and increasing the stability of the suspensions. Four distinct dispersions were optimized and applied as coatings onto stony materials used in the Built Heritage, such as sandstone, lime mortar, granite and limestone. Their effectiveness was assessed by assessing hydrophobicity of the surfaces (static water contact angle), photocatalytic activity and self-cleaning as well as water vapour permeability of the treated specimens. These transparent coatings demonstrated high compatibility with the construction materials of the Architectural Heritage and showed a synergistic effect rendering a minimized water absorption, self-cleaning ability evidenced by the reduced adsorption of soiling deposits and a reasonable degradation of any trace that might be adsorbed, as well as a protecting hydrophobic environment for the photocatalyst.

ACS Style

A. Speziale; J. F. González-Sánchez; B. Taşcı; A. Pastor; L. Sánchez; C. Fernández-Acevedo; T. Oroz-Mateo; C. Salazar; I. Navarro-Blasco; J. M. Fernández; J. I. Alvarez. Development of Multifunctional Coatings for Protecting Stones and Lime Mortars of the Architectural Heritage. International Journal of Architectural Heritage 2020, 14, 1008 -1029.

AMA Style

A. Speziale, J. F. González-Sánchez, B. Taşcı, A. Pastor, L. Sánchez, C. Fernández-Acevedo, T. Oroz-Mateo, C. Salazar, I. Navarro-Blasco, J. M. Fernández, J. I. Alvarez. Development of Multifunctional Coatings for Protecting Stones and Lime Mortars of the Architectural Heritage. International Journal of Architectural Heritage. 2020; 14 (7):1008-1029.

Chicago/Turabian Style

A. Speziale; J. F. González-Sánchez; B. Taşcı; A. Pastor; L. Sánchez; C. Fernández-Acevedo; T. Oroz-Mateo; C. Salazar; I. Navarro-Blasco; J. M. Fernández; J. I. Alvarez. 2020. "Development of Multifunctional Coatings for Protecting Stones and Lime Mortars of the Architectural Heritage." International Journal of Architectural Heritage 14, no. 7: 1008-1029.

Journal article
Published: 14 February 2019 in Journal of Cleaner Production
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This study analyses the feasibility of incorporating electric arc furnace dust (EAFD) in the production of self-compacting mortars from the point of view of durability. Two types of EAFD, previously characterized and classified as hazardous waste, were used. Siliceous filler (powder) was replaced at different ratios (25%, 50%, and 100%, by volume). The following self-compacting mortar properties were measured at different curing times: total heat of hydration, compressive strength, ultrasonic pulse velocity, pore size distribution through mercury intrusion porosimetry, shrinkage and mass loss, water absorption by capillary, water absorption capacity, bulk density, skeletal density, open porosity for water, wettability by contact angle measurement, electrical resistivity, and carbonation depth. Although some of properties linked to the durability of the mortars, such as water absorption by capillarity, wettability or carbonation, were negatively affected by the incorporation of the EAFD, the results show the feasibility of replacing siliceous filler at up to 25% and the valorisation of EAFD as a secondary raw material (SRM). This research demonstrated that EAFD can be used as SRM as an alternative to landfills, thereby contributing to the promotion of the new circular economic model pursued by the European Union.

ACS Style

Angélica Lozano-Lunar; Pedro Raposeiro da Silva; Jorge De Brito; José Ignacio Alvarez; J.M. Fernández; J.R. Jiménez. Performance and durability properties of self-compacting mortars with electric arc furnace dust as filler. Journal of Cleaner Production 2019, 219, 818 -832.

AMA Style

Angélica Lozano-Lunar, Pedro Raposeiro da Silva, Jorge De Brito, José Ignacio Alvarez, J.M. Fernández, J.R. Jiménez. Performance and durability properties of self-compacting mortars with electric arc furnace dust as filler. Journal of Cleaner Production. 2019; 219 ():818-832.

Chicago/Turabian Style

Angélica Lozano-Lunar; Pedro Raposeiro da Silva; Jorge De Brito; José Ignacio Alvarez; J.M. Fernández; J.R. Jiménez. 2019. "Performance and durability properties of self-compacting mortars with electric arc furnace dust as filler." Journal of Cleaner Production 219, no. : 818-832.

Journal article
Published: 20 September 2018 in Construction and Building Materials
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The search for answers to the environmental challenges is one of the obligations of the current society. Therefore, the optimisation of natural resources and the minimisation and revaluation of waste should be present in any activity. These purposes should be included in both the construction and energy sectors owing to the large amount of resources consumed and of pollutants and waste generated by them. The present work carries out a feasibility study of the use of fly ash from coal-fired power plants as a filler for self-compacting concrete (SCC). This kind of fly ash does not meet the compliance criteria determined by the regulations, and thus, it is non-conforming fly ash (NCFA). The dual objective of this work is the optimisation of a natural non-renewable resource and the recovery of waste, which should achieve the qualification of end of waste before being used as a by-product. For this purpose, a comparative study of three mixes is performed, namely, SCC-1 with commercial siliceous filler (SF) (SCC reference), SCC-12 with a mix 1:1 by volume of SF and NCFA, and SCC-2 with NCFA. All the mixes showed good self-compactability. The analysis of the relevant parameters, i.e., apparent and dry density, open porosity, mercury intrusion porosimetry, absorption of water by immersion, and capillarity, has been significant to know in depth the durability of the mixes. The results show that it is possible to obtain a SCC with high performance with respect to durability, attack of aggressive agents, and shrinkage by replacing the SF of siliceous nature with NCFA.

ACS Style

A.R. Esquinas; José Ignacio Alvarez; J.R. Jiménez; J.M. Fernández. Durability of self-compacting concrete made from non-conforming fly ash from coal-fired power plants. Construction and Building Materials 2018, 189, 993 -1006.

AMA Style

A.R. Esquinas, José Ignacio Alvarez, J.R. Jiménez, J.M. Fernández. Durability of self-compacting concrete made from non-conforming fly ash from coal-fired power plants. Construction and Building Materials. 2018; 189 ():993-1006.

Chicago/Turabian Style

A.R. Esquinas; José Ignacio Alvarez; J.R. Jiménez; J.M. Fernández. 2018. "Durability of self-compacting concrete made from non-conforming fly ash from coal-fired power plants." Construction and Building Materials 189, no. : 993-1006.

Journal article
Published: 09 August 2018 in Construction and Building Materials
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The pore structure of air lime mortars, formulated with aggregates of different mineralogy and grain size distribution, was evaluated with the aim of studying the influence of sand type on the microstructural modification over time and of establishing the relationship between these modifications and the mechanical behaviour. The microstructure of the mortars was determined by mercury intrusion porosimetry at 28, 90 and 360 days, and the results were compared with its mechanical characteristics, namely compressive strength, flexural strength and modulus of elasticity. A remarkable increase of mechanical strength over time was found for all mortars. An optimized grain size distribution of the sand (optimized compactness) proved to be favourable to air lime mortars compared with grain size distribution defined by standard EN 196-1, showing a good behaviour of the interlocked structure but also adequate porosity that favours lime carbonation. A relationship between the mechanical properties and the porous structure was also established: large volumes in the range of macropores tend to reduce the mechanical strength while gel pores, related with the presence of hydraulic compounds, are generally linked to an increase in strength. Overall, the assessment of the microstructure indicates that the packing density and the shape of the aggregates are the dominant parameters influencing the pore size distribution of macropores; however, the mineralogy and related characteristics also have an important impact on capillary porosity.

ACS Style

Ana Rita Santos; Maria Do Rosário Veiga; António Santos Silva; Jorge de Brito; José Ignacio Álvarez. Evolution of the microstructure of lime based mortars and influence on the mechanical behaviour: The role of the aggregates. Construction and Building Materials 2018, 187, 907 -922.

AMA Style

Ana Rita Santos, Maria Do Rosário Veiga, António Santos Silva, Jorge de Brito, José Ignacio Álvarez. Evolution of the microstructure of lime based mortars and influence on the mechanical behaviour: The role of the aggregates. Construction and Building Materials. 2018; 187 ():907-922.

Chicago/Turabian Style

Ana Rita Santos; Maria Do Rosário Veiga; António Santos Silva; Jorge de Brito; José Ignacio Álvarez. 2018. "Evolution of the microstructure of lime based mortars and influence on the mechanical behaviour: The role of the aggregates." Construction and Building Materials 187, no. : 907-922.

Journal article
Published: 26 July 2018 in Polymers
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A new range of grouts prepared by air lime and metakaolin (MK) as a pozzolanic admixture has been obtained by using as dispersing agents two polymers, namely poly-naphthalene sulfonate (PNS) and lignosulfonate (LS), with the aim of improving the fluidity of the fresh grouts. Fluidity and setting times of the grouts were assessed. Differences in the molecular architecture and in the anionic charge density explained the different adsorption of the polymers and the different performance. The higher anionic charge of PNS and its linear shape explained its better adsorption and effectiveness. The pozzolanic reaction was favoured in grouts with PNS, achieving the highest values of compressive strength (4.8 MPa after 182 curing days). The addition of PNS on lime grouts slightly decreased the frost resistance of the grouts (from 24 freeze-thaw cycles for the polymer-free samples to 19 or 20 cycles with 0.5 or 1 wt % of PNS). After the magnesium sulphate attack, grouts were altered by decalcification of hydrated phases and by formation of hexahydrite and gypsum. A protective role of portlandite against magnesium sulphate attack was clearly identified. Accordingly, the polymer LS, which preserves a significant amount of Ca(OH)2, could be an alternative for the obtaining of grouts requiring high sulphate attack resistance.

ACS Style

Adrián Duran; Jesús F. González-Sánchez; José M. Fernández; Rafael Sirera; Íñigo Navarro-Blasco; José I. Alvarez. Influence of Two Polymer-Based Superplasticizers (Poly-naphthalene Sulfonate, PNS, and Lignosulfonate, LS) on Compressive and Flexural Strength, Freeze-Thaw, and Sulphate Attack Resistance of Lime-Metakaolin Grouts. Polymers 2018, 10, 824 .

AMA Style

Adrián Duran, Jesús F. González-Sánchez, José M. Fernández, Rafael Sirera, Íñigo Navarro-Blasco, José I. Alvarez. Influence of Two Polymer-Based Superplasticizers (Poly-naphthalene Sulfonate, PNS, and Lignosulfonate, LS) on Compressive and Flexural Strength, Freeze-Thaw, and Sulphate Attack Resistance of Lime-Metakaolin Grouts. Polymers. 2018; 10 (8):824.

Chicago/Turabian Style

Adrián Duran; Jesús F. González-Sánchez; José M. Fernández; Rafael Sirera; Íñigo Navarro-Blasco; José I. Alvarez. 2018. "Influence of Two Polymer-Based Superplasticizers (Poly-naphthalene Sulfonate, PNS, and Lignosulfonate, LS) on Compressive and Flexural Strength, Freeze-Thaw, and Sulphate Attack Resistance of Lime-Metakaolin Grouts." Polymers 10, no. 8: 824.

Journal article
Published: 01 February 2018 in Construction and Building Materials
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ACS Style

Álvaro Romero Esquinas; José Ignacio Alvarez; José Ramón Jiménez; J.M. Fernández; Jorge de Brito. Durability of self-compacting concrete made with recovery filler from hot-mix asphalt plants. Construction and Building Materials 2018, 161, 407 -419.

AMA Style

Álvaro Romero Esquinas, José Ignacio Alvarez, José Ramón Jiménez, J.M. Fernández, Jorge de Brito. Durability of self-compacting concrete made with recovery filler from hot-mix asphalt plants. Construction and Building Materials. 2018; 161 ():407-419.

Chicago/Turabian Style

Álvaro Romero Esquinas; José Ignacio Alvarez; José Ramón Jiménez; J.M. Fernández; Jorge de Brito. 2018. "Durability of self-compacting concrete made with recovery filler from hot-mix asphalt plants." Construction and Building Materials 161, no. : 407-419.

Journal article
Published: 01 February 2018 in Construction and Building Materials
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ACS Style

M. Pérez-Nicolás; J. Plank; D. Ruiz-Izuriaga; I. Navarro-Blasco; J.M. Fernández; J.I. Alvarez. Photocatalytically active coatings for cement and air lime mortars: Enhancement of the activity by incorporation of superplasticizers. Construction and Building Materials 2018, 162, 628 -648.

AMA Style

M. Pérez-Nicolás, J. Plank, D. Ruiz-Izuriaga, I. Navarro-Blasco, J.M. Fernández, J.I. Alvarez. Photocatalytically active coatings for cement and air lime mortars: Enhancement of the activity by incorporation of superplasticizers. Construction and Building Materials. 2018; 162 ():628-648.

Chicago/Turabian Style

M. Pérez-Nicolás; J. Plank; D. Ruiz-Izuriaga; I. Navarro-Blasco; J.M. Fernández; J.I. Alvarez. 2018. "Photocatalytically active coatings for cement and air lime mortars: Enhancement of the activity by incorporation of superplasticizers." Construction and Building Materials 162, no. : 628-648.

Journal article
Published: 14 October 2017 in Nanomaterials
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Mortars with two different binders (Portland cement (PC) and high alumina cement (HAC)) were modified upon the bulk incorporation of nano-structured photocatalytic additives (bare TiO2, and TiO2 doped with either iron (Fe-TiO2) or vanadium (V-TiO2)). Plastic and hardened state properties of these mortars were assessed in order to study the influence of these nano-additives. Water demand was increased, slightly by bare TiO2 and Fe-TiO2, and strongly by V-TiO2, in agreement with the reduction of the particle size and the tendency to agglomerate. Isothermal calorimetry showed that hydration of the cementitious matrices was accelerated due to additional nucleation sites offered by the nano-additives. TiO2 and doped TiO2 did not show pozzolanic reactivity in the binding systems. Changes in the pore size distribution, mainly the filler effect of the nano-additives, accounted for the increase in compressive strengths measured for HAC mortars. A complex microstructure was seen in calcium aluminate cement mortars, strongly dependent on the curing conditions. Fe-TiO2 was found to be homogeneously distributed whereas the tendency of V-TiO2 to agglomerate was evidenced by elemental distribution maps. Water absorption capacity was not affected by the nano-additive incorporation in HAC mortars, which is a favourable feature for the application of these mortars.

ACS Style

María Pérez-Nicolás; Íñigo Navarro-Blasco; José M. Fernández; José Ignacio Alvarez. The Effect of TiO2 Doped Photocatalytic Nano-Additives on the Hydration and Microstructure of Portland and High Alumina Cements. Nanomaterials 2017, 7, 329 .

AMA Style

María Pérez-Nicolás, Íñigo Navarro-Blasco, José M. Fernández, José Ignacio Alvarez. The Effect of TiO2 Doped Photocatalytic Nano-Additives on the Hydration and Microstructure of Portland and High Alumina Cements. Nanomaterials. 2017; 7 (10):329.

Chicago/Turabian Style

María Pérez-Nicolás; Íñigo Navarro-Blasco; José M. Fernández; José Ignacio Alvarez. 2017. "The Effect of TiO2 Doped Photocatalytic Nano-Additives on the Hydration and Microstructure of Portland and High Alumina Cements." Nanomaterials 7, no. 10: 329.

Journal article
Published: 01 September 2017 in Construction and Building Materials
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Mortars made with Portland cement, two different calcium aluminate cements and air lime were chosen to incorporate photocatalytic additives, because they have large exposed surfaces that boost the photochemical oxidation (PCO) of atmospheric pollutants such as nitrogen oxides. TiO2 as reference catalyst, and two doped titania, Fe-TiO2 and V-TiO2, which were expected to increase the sensitivity of the additives towards the visible light, were studied. Cementing matrices, particularly air lime and high alumina cement mortars, yielded significant amounts of NO removal under the three illumination conditions studied (UV, solar and visible light), with high selectivity response for NO abatement (up to 60 to 80%) and low NO2 release. The presence of calcium carbonate has been shown to have a synergistic effect, enhancing the PCO of these mortars under different light sources

ACS Style

M. Pérez-Nicolás; Iñigo Navarro-Blasco; José María Fernández; José Ignacio Alvarez. Atmospheric NOx removal: Study of cement mortars with iron- and vanadium-doped TiO2 as visible light–sensitive photocatalysts. Construction and Building Materials 2017, 149, 257 -271.

AMA Style

M. Pérez-Nicolás, Iñigo Navarro-Blasco, José María Fernández, José Ignacio Alvarez. Atmospheric NOx removal: Study of cement mortars with iron- and vanadium-doped TiO2 as visible light–sensitive photocatalysts. Construction and Building Materials. 2017; 149 ():257-271.

Chicago/Turabian Style

M. Pérez-Nicolás; Iñigo Navarro-Blasco; José María Fernández; José Ignacio Alvarez. 2017. "Atmospheric NOx removal: Study of cement mortars with iron- and vanadium-doped TiO2 as visible light–sensitive photocatalysts." Construction and Building Materials 149, no. : 257-271.

Journal article
Published: 01 April 2016 in Cement and Concrete Research
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Polynaphtalenesulfonate (PNS) and lignosulfonate (LS) were tested as superplasticizers in pastes and mortars of pure air lime and air lime with a pozzolanic additive, nanosilica (NS). LS showed a better plasticizing effect than PNS: the flowability of the samples with LS as well as the slump retention over time was larger. LS strongly hindered carbonation due to its ability to form Ca2 + complexes. In mortars with NS, PNS was seen to interfere with the C-S-H formation, resulting in lower mechanical strengths. Adsorption isotherms and zeta potential showed that PNS was more adsorbed than LS onto lime and C-S-H particles. PNS acted mainly through electrostatic repulsion owing to its high anionic charge density and flat adsorption. However, LS was more efficient as superplasticizer in air lime media, steric hindrance being the main mechanism responsible for avoiding flocculation. Furthermore, LS yielded high compressive strengths in mortars with NS.

ACS Style

M. Pérez-Nicolás; Adrian Duran; Iñigo Navarro-Blasco; José María Fernández; Rafael Sirera; J.I. Alvarez. Study on the effectiveness of PNS and LS superplasticizers in air lime-based mortars. Cement and Concrete Research 2016, 82, 11 -22.

AMA Style

M. Pérez-Nicolás, Adrian Duran, Iñigo Navarro-Blasco, José María Fernández, Rafael Sirera, J.I. Alvarez. Study on the effectiveness of PNS and LS superplasticizers in air lime-based mortars. Cement and Concrete Research. 2016; 82 ():11-22.

Chicago/Turabian Style

M. Pérez-Nicolás; Adrian Duran; Iñigo Navarro-Blasco; José María Fernández; Rafael Sirera; J.I. Alvarez. 2016. "Study on the effectiveness of PNS and LS superplasticizers in air lime-based mortars." Cement and Concrete Research 82, no. : 11-22.

Journal article
Published: 01 March 2016 in Cement and Concrete Research
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The effect of chlorides and nitrates of Li(I), Cr(III), Zn(II), Cu(II), Pb(II) nitrate and Cr(VI) (chromate) on the early hydration of ternary cement system of calcium aluminates (CA, CA2, C12A7) was reported. Li(I) and Cr(III) caused a strong acceleration of the hydration, while Zn(II) as well as chromate gave rise to a slight acceleration. On the contrary, Pb(II) and Cu(II) retarded the hydration. A clear formation of AFm phases during the first hydration stages was found and related to the acceleration ability. Anions (nitrate or chloride as counterions or even chromate) were able to be incorporated into the interlayer space of AFm, yielding insoluble and stable compounds. A balance between the insolubility of the metal hydroxides (dependant on the low amphoteric character of the compound) and the ability of the formation of AFm hydrates seems to be very important to lean the equilibrium towards the retarding of the hydration or towards the acceleration, respectively.

ACS Style

Adrian Duran; Rafael Sirera; M. Pérez-Nicolás; Iñigo Navarro-Blasco; J.M. Fernández; J.I. Alvarez. Study of the early hydration of calcium aluminates in the presence of different metallic salts. Cement and Concrete Research 2016, 81, 1 -15.

AMA Style

Adrian Duran, Rafael Sirera, M. Pérez-Nicolás, Iñigo Navarro-Blasco, J.M. Fernández, J.I. Alvarez. Study of the early hydration of calcium aluminates in the presence of different metallic salts. Cement and Concrete Research. 2016; 81 ():1-15.

Chicago/Turabian Style

Adrian Duran; Rafael Sirera; M. Pérez-Nicolás; Iñigo Navarro-Blasco; J.M. Fernández; J.I. Alvarez. 2016. "Study of the early hydration of calcium aluminates in the presence of different metallic salts." Cement and Concrete Research 81, no. : 1-15.

Journal article
Published: 01 August 2015 in Journal of Environmental Management
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Phosphate coating hazardous wastes originated from the automotive industry were efficiently encapsulated by an acid-base reaction between phosphates present in the sludge and calcium aluminate cement, yielding very inert and stable monolithic blocks of amorphous calcium phosphate (ACP). Two different compositions of industrial sludge were characterized and loaded in ratios ranging from 10 to 50 wt.%. Setting times and compressive strengths were recorded to establish the feasibility of this method to achieve a good handling and a safe landfilling of these samples. Short solidification periods were found and leaching tests showed an excellent retention for toxic metals (Zn, Ni, Cu, Cr and Mn) and for organic matter. Retentions over 99.9% for Zn and Mn were observed even for loadings as high as 50 wt.% of the wastes. The formation of ACP phase of low porosity and high stability accounted for the effective immobilization of the hazardous components of the waste

ACS Style

I. Navarro-Blasco; A. Duran; M. Pérez-Nicolás; J.M. Fernández; R. Sirera; J.I. Alvarez. A safer disposal of hazardous phosphate coating sludge by formation of an amorphous calcium phosphate matrix. Journal of Environmental Management 2015, 159, 288 -300.

AMA Style

I. Navarro-Blasco, A. Duran, M. Pérez-Nicolás, J.M. Fernández, R. Sirera, J.I. Alvarez. A safer disposal of hazardous phosphate coating sludge by formation of an amorphous calcium phosphate matrix. Journal of Environmental Management. 2015; 159 ():288-300.

Chicago/Turabian Style

I. Navarro-Blasco; A. Duran; M. Pérez-Nicolás; J.M. Fernández; R. Sirera; J.I. Alvarez. 2015. "A safer disposal of hazardous phosphate coating sludge by formation of an amorphous calcium phosphate matrix." Journal of Environmental Management 159, no. : 288-300.

Journal article
Published: 01 April 2015 in Cement and Concrete Research
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Photocatalytic activity of TiO2 was studied in two types of Calcium Aluminate Cement (CAC) under two different curing regimes. The effect of the TiO2 addition on the setting time, consistency and mechanical properties of the CACs was evaluated. The abatement of gaseous pollutants (NOx) under UV irradiation was also assessed. These cementitious matrices were found to successfully retain NO2: more abundant presence of aluminates in white cement (w-CAC, iron-lean) helped to better adsorb NO2, thus improving the conversion performance of the catalyst resulting in a larger NOx removal under UV irradiation. As evidenced by XRD, SEM, EDAX and zeta potential analyses, the presence of ferrite in dark cement (d-CAC, iron-reach) induced a certain chemical interaction with TiO2. The experimental findings suggest the formation of new iron titanate phases, namely pseudobrookite. The reduced band-gap energy of these compounds compared with that of TiO2 accounts for the photocatalytic activity of these samples

ACS Style

M. Pérez-Nicolás; J. Balbuena; Manuel Cruz Yusta; Luis Sanchez; I. Navarro-Blasco; José María Fernández; José Ignacio Alvarez. Photocatalytic NOx abatement by calcium aluminate cements modified with TiO2: Improved NO2 conversion. Cement and Concrete Research 2015, 70, 67 -76.

AMA Style

M. Pérez-Nicolás, J. Balbuena, Manuel Cruz Yusta, Luis Sanchez, I. Navarro-Blasco, José María Fernández, José Ignacio Alvarez. Photocatalytic NOx abatement by calcium aluminate cements modified with TiO2: Improved NO2 conversion. Cement and Concrete Research. 2015; 70 ():67-76.

Chicago/Turabian Style

M. Pérez-Nicolás; J. Balbuena; Manuel Cruz Yusta; Luis Sanchez; I. Navarro-Blasco; José María Fernández; José Ignacio Alvarez. 2015. "Photocatalytic NOx abatement by calcium aluminate cements modified with TiO2: Improved NO2 conversion." Cement and Concrete Research 70, no. : 67-76.

Journal article
Published: 01 December 2014 in Construction and Building Materials
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Two polycarboxylate ether copolymers were assessed as superplasticizers (SPs) for hydrated lime pastes modified with two reactive compounds, nanosilica (NS) and ceramic metakaolin (MK). Characterization of the molecular structure of the SPs by Size Exclusion Chromatography, XRD, FTIR and MALDI-TOF (Matrix Assisted Laser Desorption Ionization Time-of-Flight) mass spectrometry was performed. The structures of the polymers were seen to be star- and worm-like shapes. A close relationship was found between the molecular architecture and the flowability of the pastes, being the star-shaped plasticizer the most efficient. Zeta potential assessment allowed us to elucidate a steric hindrance as the main action mechanism for these polymers. The large specific surface area of nanosilica led to a large SPs consumption as compared with metakaolin with lower surface area. However, SPs in MK-lime samples were attached favourably on the C-S-H and aluminate hydrates, so that the dispersing action was greater with respect to NS-lime suspensions

ACS Style

I. Navarro-Blasco; M. Pérez-Nicolás; J.M. Fernández; A. Duran; R. Sirera; J.I. Alvarez. Assessment of the interaction of polycarboxylate superplasticizers in hydrated lime pastes modified with nanosilica or metakaolin as pozzolanic reactives. Construction and Building Materials 2014, 73, 1 -12.

AMA Style

I. Navarro-Blasco, M. Pérez-Nicolás, J.M. Fernández, A. Duran, R. Sirera, J.I. Alvarez. Assessment of the interaction of polycarboxylate superplasticizers in hydrated lime pastes modified with nanosilica or metakaolin as pozzolanic reactives. Construction and Building Materials. 2014; 73 ():1-12.

Chicago/Turabian Style

I. Navarro-Blasco; M. Pérez-Nicolás; J.M. Fernández; A. Duran; R. Sirera; J.I. Alvarez. 2014. "Assessment of the interaction of polycarboxylate superplasticizers in hydrated lime pastes modified with nanosilica or metakaolin as pozzolanic reactives." Construction and Building Materials 73, no. : 1-12.

Journal article
Published: 01 July 2014 in Journal of Environmental Management
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Polyphosphate-modified calcium aluminate cement matrices were prepared by using aqueous solutions polluted with toxic metals as mixing water to obtain waste-containing solid blocks with improved management and disposal. Synthetically contaminated waters containing either Pb or Cu or Zn were incorporated into phosphoaluminate cement mortars and the effects of the metal’s presence on setting time and mechanical performance were assessed. Sorption and leaching tests were also executed and both retention and release patterns were investigated. For all three metals, high uptake capacities as well as percentages of retention larger than 99.9% were measured. Both Pb and Cu were seen to be largely compatible with this cementitious matrix, rendering the obtained blocks suitable for landfilling or for building purposes. However, Zn spoilt the compressive strength values because of its reaction with hydrogen phosphate anions, hindering the development of the binding matrix

ACS Style

José María Fernández; Iñigo Navarro-Blasco; Adrian Duran; Rafael Sirera; J.I. Alvarez. Treatment of toxic metal aqueous solutions: Encapsulation in a phosphate-calcium aluminate matrix. Journal of Environmental Management 2014, 140, 1 -13.

AMA Style

José María Fernández, Iñigo Navarro-Blasco, Adrian Duran, Rafael Sirera, J.I. Alvarez. Treatment of toxic metal aqueous solutions: Encapsulation in a phosphate-calcium aluminate matrix. Journal of Environmental Management. 2014; 140 ():1-13.

Chicago/Turabian Style

José María Fernández; Iñigo Navarro-Blasco; Adrian Duran; Rafael Sirera; J.I. Alvarez. 2014. "Treatment of toxic metal aqueous solutions: Encapsulation in a phosphate-calcium aluminate matrix." Journal of Environmental Management 140, no. : 1-13.