Maximina Romero - Academia.edu (original) (raw)

Papers by Maximina Romero

Journal of Thermal Analysis and Calorimetry, 2015

Thermal approach to evaluate the sintering-crystallization ability in a nepheline-forsterite-base... more Thermal approach to evaluate the sintering-crystallization ability in a nepheline-forsterite-based glass-ceramics.

Applied Sciences

The incorporation of coal fly ash (CFA) in fired clay bricks (FCBs), as a clay replacement, contr... more The incorporation of coal fly ash (CFA) in fired clay bricks (FCBs), as a clay replacement, contributes toward cleaner production practices. CFA disposal is an important issue worldwide due to its huge volume and to its potential negative environmental impacts, and currently does not have a recovery route due to its high concentration in unburned materials. In this study, the impact of the incorporation of two CFA, with different content of unburned carbon, FAA (low LOI) and FAB (high LOI) in FCBs, from a technical and environmental point of view was conducted. Unburned carbon plays an important role on the final properties of FCBs. The thermal decomposition during the firing process promotes an increase of water absorption, decreasing the flexural strength as the porosity increases, although the technical and mechanical properties of samples containing up to 30% FAA and percentages of 20% FAB are acceptable. The leaching behaviour showed an immobilisation of Cr and Se in FCBs while...

Construction and Building Materials, 2018

h i g h l i g h t s The addition of phosphogypsum waste in ceramic bodies was evaluated. The new ... more h i g h l i g h t s The addition of phosphogypsum waste in ceramic bodies was evaluated. The new ceramic tiles shown even better technological properties than standards. No significant environmental impact and human risk on use this building material. The use of this waste can reduce the raw materials demands and phosphogypsum piles.

Solar Energy, 2018

This research aims to study the feasibility of applying real concentrated solar radiation to achi... more This research aims to study the feasibility of applying real concentrated solar radiation to achieve the energy needed for melting glass frits. For this purpose, five glass compositions corresponding to different types of commercial frits were prepared. For comparison, the batches were melted by both in a solar furnace using concentrated solar energy (CSE) and in an electric furnace. The final frits were characterised by means of X-ray Fluorescence, X-ray Diffraction, Differential Thermal Analysis, Field Emission Scanning Electron Microscopy and Fourier Transformed Infrared Spectrometry. Results show that the frits prepared by CSE present short-range order, thermal behaviour and microstructure analogous to frits prepared in electric furnace. Moreover, the use of CSE for manufacturing glass frits reduces the melting time in about 80%, which leads to both lower corrosion of crucible wall and lower boron volatilization.

Thermochimica Acta, 2015

Devitrification behavior and preferred crystallization mechanism of glasses based on fluorrichter... more Devitrification behavior and preferred crystallization mechanism of glasses based on fluorrichterite (Na 2 CaMg 5 Si 8 O 22 F 2) composition.

Waste and Biomass Valorization, 2016

This work analyses and evaluates potential applications for several inorganic wastes and intermed... more This work analyses and evaluates potential applications for several inorganic wastes and intermediate materials, called co-products, generated in the TiO 2 pigment production industry through the sulphate method. For this purpose, a physical-chemical characterisation of the input materials (ilmenite and slag), wastes (sludge and red gypsum), and co-products (two ferrous sulphates, mono and hepta-hydrated) was carried out. In addition, because the TiO 2 pigment production activity is a Naturally Occurring Radioactive Material industry, a radiological characterisation was also undertaken. The main objective was to gain basic information for the application (actual or potential) of these co-products and wastes in fields such as agriculture, construction, and civil engineering. For each specific application of these wastes and coproducts, additional studies were carried out to evaluate their appropriateness with respect to technical properties and their health and environmental impact. The results obtained in this work have revealed several lines of research with potential commercial applications.

Materiales de Construcción, 2015

Porcelain stoneware is a strongly sintered ceramic material fabricated from ball clays-quartzfeld... more Porcelain stoneware is a strongly sintered ceramic material fabricated from ball clays-quartzfeldspar mixtures. Porcelain stoneware is characterized by its excellent technical and functional properties (low water absorption, high mechanical properties, resistant to chemical substances and cleaning agents, aesthetic possibilities …). These characteristic and technical features make that among the different types of ceramic tile, porcelain stoneware is the ceramic product that in the last years has best withstood the economic crisis in the construction sector. These properties are related to the microstructure of porcelain stoneware, which is a grain and bond type with large particles of filler (quartz), mullite crystals, a silica-rich amorphous phase and porosity. The understanding of the relationship between the microstructure and the properties of porcelain stoneware is hardly important for the development and design of these materials whose tendency is the manufacture of thinner tiles with higher dimensions but must continue to comply the specific technical requirements.

Journal of Environmental Chemical Engineering, 2015

The authors thank Metalquex SL (Zaragoza, Spain) for supplying the wastes and CSIC for its financ... more The authors thank Metalquex SL (Zaragoza, Spain) for supplying the wastes and CSIC for its financial support (P.I.E 201260E115). We also gratefully acknowledge the assistance provided by Dr. Blanca Casal for helpful discussion during this research. R. Sanchez-Hernandez thanks MINECO for grant BES-2013-066269.

Characterization Techniques of Glasses and Ceramics, 1999

The convergent beam electron diffraction (CBED) technique, as well as the electron microdiffracti... more The convergent beam electron diffraction (CBED) technique, as well as the electron microdiffraction methods are currently used in analytical electron microscopy for materials characterization. These diffraction methods allow the identification of very small crystalline phases and tri-dimensional crystallographic analysis with high spatial resolution through the application of a very thin electron beam and wide diffraction angle through the specimen in a transmission electron microscope (TEM). Despite the wide range of analytical possibilities, its use in the characterization of ceramics, glass-ceramics and their raw materials has been scarce. Therefore, in this chapter are shown the basic principles of CBED as well as microdiffraction for the crystallographic analysis of ceramics both from our own research and by reviewing some examples of applications from the literature.

Boletin de la Sociedad Espanola de Ceramica y Vidrio, 2011

En este trabajo se muestran los resultados de un estudio de valorización de la ceniza de cáscara ... more En este trabajo se muestran los resultados de un estudio de valorización de la ceniza de cáscara de arroz como materia prima en la obtención de materiales vitrocerámicos. Se ha formulado un vidrio en el sistema base MgO-Al 2 O 3-SiO 2 incorporando B 2 O 3 y Na 2 O para facilitar los procesos de fusión y colado del vidrio. El vidrio se ha caracterizado mediante la determinación de su composición química. Su comportamiento frente a la sinterización se ha llevado a cabo mediante Microscopía de Calefacción (MC). La estabilidad térmica de las muestras y el mecanismo de cristalización preferente se ha estudiado mediante Análisis Térmico Diferencial (ATD). La mineralogía de los materiales vitrocerámicos se ha llevado a cabo por Difracción de rayos-X (DRX). Los resultados obtenidos muestran que es posible utilizar ceniza de cáscara de arroz para producir materiales vitrocerámicos mediante un proceso de sinterización seguido de cristalización, con nefelina (Na 2 O•Al 2 O 3 •2SiO 2) como fase cristalina mayoritaria en el intervalo de temperatura 700º-950ºC y forsterita (2MgO•SiO 2) a temperaturas superiores a 950ºC.

MRS Proceedings, 2009

The metallurgical industry of ferrous and non-ferrous metals produce huge amount of wastes. In Sl... more The metallurgical industry of ferrous and non-ferrous metals produce huge amount of wastes. In Slovakia, the factory for nickel production was closed in 1993, but around 5.5 kt of wastes remain in a dump. This waste was used as a model sorbent of heavy metals (Cu, Cd, Co) from wastewater treatments. The TCLP (Toxicity Characteristic Leaching Procedure) test of precipitated heavy metals on waste materials has confirmed the necessity of waste stabilization. The microwave vitrification was applied because of a high content of iron in waste. After vitrification, the chemical durability and microhardness by indentation have been tested in the glassy and glassceramics obtained.

desde su fundación no sólo ha realizado a lo largo de su ya larga historia investigaciones y vali... more desde su fundación no sólo ha realizado a lo largo de su ya larga historia investigaciones y valiosas aportaciones científicas y técnicas en el campo de los materiales cerámicos y vidrios, sino que además fue uno de los principales fundadores de la actual Sociedad Española de Cerámica y Vidrio (SECV) con la destacada participación de D. Francisco Arredondo y Verdú. En los últimos once años esta línea de investigación se ha visto reforzada con la creación del Grupo y Laboratorio de Materiales Vítreos y Cerámicos, por lo que se realiza una revisión de la relación de este centro con este tipo de materiales, recordándose los investigadores y publicaciones que más destacaron en este camp. Se realiza finalmente un análisis de la situación actual y de las perspectivas de I+D+i en este tipo de materiales de construcción, haciendo especial énfasis en sus aplicaciones en fachadas ventiladas y del factor dinamizador de la investigación científica que implicará el reto tecnológico de la aplicación de plaquetas cerámicas en este tipo de fachadas.

Ceramics International, 2013

This work presents the results of a study focused on the development of forsterite-nepheline glas... more This work presents the results of a study focused on the development of forsterite-nepheline glass-ceramic with the use of rice husk ash (RHA) as a silica source. The glass-ceramics were produced by a sintering process of a glassy frit formulated in the MgO-Al 2 O 3-SiO 2 base system with the addition of B 2 O 3 and Na 2 O to facilitate the melting and pouring processes. The crystallisation study was carried out by depicting the TTT curve (Time-Temperature-Transformation). The mineralogical characterisation of the glass-ceramic materials was carried out using X-ray diffraction (XRD). The crystallisation activation energies were calculated by the Kissinger method. The results obtained show that devitrification of the RHA glass leads to a glass-ceramic material composed of nepheline (Na 2 O•Al 2 O 3 •2SiO 2) and forsterite (2MgO•SiO 2). A study of the microstructure by scanning electron microscopy (SEM) allowed to establish the morphological evolution in both the shape and spatial arrangement of the nepheline and forsterite crystals on heating.

Ceramics International, 2013

Technological properties of glass-ceramic tiles obtained using rice husk ash as silica precursor.

Journal of Analytical and Applied Pyrolysis, 2012

Thermolysis of fibreglass polyester composite and reutilisation of the glass fibre residue to obt... more Thermolysis of fibreglass polyester composite and reutilisation of the glass fibre residue to obtain a glass-ceramic material.

La presente invención se refiere a un método para preparar fritas de vidrio suministrando la ener... more La presente invención se refiere a un método para preparar fritas de vidrio suministrando la energía total requerida en el proceso por medio de radiación solar concentrada.Se relaciona además con un dispositivo para llevar a cabo dicho método que comprende elementos tales como un espejo plano solar, un obturador del haz de luz solar y un concentrador de radiación solar El dispositivo incluye además medios para almacenar, alimentar y contener las materias primas. Se derivan varias ventajas del uso del método y dispositivo de la presente invención, que se pueden resumir en una reducción en el consumo de energía y en un aumento de la productividad del procesoPeer reviewedConsejo Superior de Investigaciones Científicas (España)B2 Patente con examen previ

Materials

Lightweight aggregates are extensively used in construction and other industrial applications due... more Lightweight aggregates are extensively used in construction and other industrial applications due to their technological characteristics. The extraction of natural aggregates results in serious environmental effects. Thus, within the circular economy concept, the valorization of waste through the optimization of materials and product design is encouraged. In this work, glass lightweight aggregates were prepared from mixtures of white glass cullet and carbonate wastes from mining (wastes originating from the extraction, manufacture and marketing of magnesite and its derivatives) and the food industry (eggshell and mussel shell). The effects of different processing parameters, such as the particle size of the base glass, percentage of the blowing additive, shaping method, heating rate, temperature and processing time, were evaluated. The results indicate that the mineralogical composition of the blowing agent and the particle size of the base glass are the two processing parameters wi...

Journal of Thermal Analysis and Calorimetry, 2015

Thermal approach to evaluate the sintering-crystallization ability in a nepheline-forsterite-base... more Thermal approach to evaluate the sintering-crystallization ability in a nepheline-forsterite-based glass-ceramics.

Applied Sciences

The incorporation of coal fly ash (CFA) in fired clay bricks (FCBs), as a clay replacement, contr... more The incorporation of coal fly ash (CFA) in fired clay bricks (FCBs), as a clay replacement, contributes toward cleaner production practices. CFA disposal is an important issue worldwide due to its huge volume and to its potential negative environmental impacts, and currently does not have a recovery route due to its high concentration in unburned materials. In this study, the impact of the incorporation of two CFA, with different content of unburned carbon, FAA (low LOI) and FAB (high LOI) in FCBs, from a technical and environmental point of view was conducted. Unburned carbon plays an important role on the final properties of FCBs. The thermal decomposition during the firing process promotes an increase of water absorption, decreasing the flexural strength as the porosity increases, although the technical and mechanical properties of samples containing up to 30% FAA and percentages of 20% FAB are acceptable. The leaching behaviour showed an immobilisation of Cr and Se in FCBs while...

Construction and Building Materials, 2018

h i g h l i g h t s The addition of phosphogypsum waste in ceramic bodies was evaluated. The new ... more h i g h l i g h t s The addition of phosphogypsum waste in ceramic bodies was evaluated. The new ceramic tiles shown even better technological properties than standards. No significant environmental impact and human risk on use this building material. The use of this waste can reduce the raw materials demands and phosphogypsum piles.

Solar Energy, 2018

This research aims to study the feasibility of applying real concentrated solar radiation to achi... more This research aims to study the feasibility of applying real concentrated solar radiation to achieve the energy needed for melting glass frits. For this purpose, five glass compositions corresponding to different types of commercial frits were prepared. For comparison, the batches were melted by both in a solar furnace using concentrated solar energy (CSE) and in an electric furnace. The final frits were characterised by means of X-ray Fluorescence, X-ray Diffraction, Differential Thermal Analysis, Field Emission Scanning Electron Microscopy and Fourier Transformed Infrared Spectrometry. Results show that the frits prepared by CSE present short-range order, thermal behaviour and microstructure analogous to frits prepared in electric furnace. Moreover, the use of CSE for manufacturing glass frits reduces the melting time in about 80%, which leads to both lower corrosion of crucible wall and lower boron volatilization.

Thermochimica Acta, 2015

Devitrification behavior and preferred crystallization mechanism of glasses based on fluorrichter... more Devitrification behavior and preferred crystallization mechanism of glasses based on fluorrichterite (Na 2 CaMg 5 Si 8 O 22 F 2) composition.

Waste and Biomass Valorization, 2016

This work analyses and evaluates potential applications for several inorganic wastes and intermed... more This work analyses and evaluates potential applications for several inorganic wastes and intermediate materials, called co-products, generated in the TiO 2 pigment production industry through the sulphate method. For this purpose, a physical-chemical characterisation of the input materials (ilmenite and slag), wastes (sludge and red gypsum), and co-products (two ferrous sulphates, mono and hepta-hydrated) was carried out. In addition, because the TiO 2 pigment production activity is a Naturally Occurring Radioactive Material industry, a radiological characterisation was also undertaken. The main objective was to gain basic information for the application (actual or potential) of these co-products and wastes in fields such as agriculture, construction, and civil engineering. For each specific application of these wastes and coproducts, additional studies were carried out to evaluate their appropriateness with respect to technical properties and their health and environmental impact. The results obtained in this work have revealed several lines of research with potential commercial applications.

Materiales de Construcción, 2015

Porcelain stoneware is a strongly sintered ceramic material fabricated from ball clays-quartzfeld... more Porcelain stoneware is a strongly sintered ceramic material fabricated from ball clays-quartzfeldspar mixtures. Porcelain stoneware is characterized by its excellent technical and functional properties (low water absorption, high mechanical properties, resistant to chemical substances and cleaning agents, aesthetic possibilities …). These characteristic and technical features make that among the different types of ceramic tile, porcelain stoneware is the ceramic product that in the last years has best withstood the economic crisis in the construction sector. These properties are related to the microstructure of porcelain stoneware, which is a grain and bond type with large particles of filler (quartz), mullite crystals, a silica-rich amorphous phase and porosity. The understanding of the relationship between the microstructure and the properties of porcelain stoneware is hardly important for the development and design of these materials whose tendency is the manufacture of thinner tiles with higher dimensions but must continue to comply the specific technical requirements.

Journal of Environmental Chemical Engineering, 2015

The authors thank Metalquex SL (Zaragoza, Spain) for supplying the wastes and CSIC for its financ... more The authors thank Metalquex SL (Zaragoza, Spain) for supplying the wastes and CSIC for its financial support (P.I.E 201260E115). We also gratefully acknowledge the assistance provided by Dr. Blanca Casal for helpful discussion during this research. R. Sanchez-Hernandez thanks MINECO for grant BES-2013-066269.

Characterization Techniques of Glasses and Ceramics, 1999

The convergent beam electron diffraction (CBED) technique, as well as the electron microdiffracti... more The convergent beam electron diffraction (CBED) technique, as well as the electron microdiffraction methods are currently used in analytical electron microscopy for materials characterization. These diffraction methods allow the identification of very small crystalline phases and tri-dimensional crystallographic analysis with high spatial resolution through the application of a very thin electron beam and wide diffraction angle through the specimen in a transmission electron microscope (TEM). Despite the wide range of analytical possibilities, its use in the characterization of ceramics, glass-ceramics and their raw materials has been scarce. Therefore, in this chapter are shown the basic principles of CBED as well as microdiffraction for the crystallographic analysis of ceramics both from our own research and by reviewing some examples of applications from the literature.

Boletin de la Sociedad Espanola de Ceramica y Vidrio, 2011

En este trabajo se muestran los resultados de un estudio de valorización de la ceniza de cáscara ... more En este trabajo se muestran los resultados de un estudio de valorización de la ceniza de cáscara de arroz como materia prima en la obtención de materiales vitrocerámicos. Se ha formulado un vidrio en el sistema base MgO-Al 2 O 3-SiO 2 incorporando B 2 O 3 y Na 2 O para facilitar los procesos de fusión y colado del vidrio. El vidrio se ha caracterizado mediante la determinación de su composición química. Su comportamiento frente a la sinterización se ha llevado a cabo mediante Microscopía de Calefacción (MC). La estabilidad térmica de las muestras y el mecanismo de cristalización preferente se ha estudiado mediante Análisis Térmico Diferencial (ATD). La mineralogía de los materiales vitrocerámicos se ha llevado a cabo por Difracción de rayos-X (DRX). Los resultados obtenidos muestran que es posible utilizar ceniza de cáscara de arroz para producir materiales vitrocerámicos mediante un proceso de sinterización seguido de cristalización, con nefelina (Na 2 O•Al 2 O 3 •2SiO 2) como fase cristalina mayoritaria en el intervalo de temperatura 700º-950ºC y forsterita (2MgO•SiO 2) a temperaturas superiores a 950ºC.

MRS Proceedings, 2009

The metallurgical industry of ferrous and non-ferrous metals produce huge amount of wastes. In Sl... more The metallurgical industry of ferrous and non-ferrous metals produce huge amount of wastes. In Slovakia, the factory for nickel production was closed in 1993, but around 5.5 kt of wastes remain in a dump. This waste was used as a model sorbent of heavy metals (Cu, Cd, Co) from wastewater treatments. The TCLP (Toxicity Characteristic Leaching Procedure) test of precipitated heavy metals on waste materials has confirmed the necessity of waste stabilization. The microwave vitrification was applied because of a high content of iron in waste. After vitrification, the chemical durability and microhardness by indentation have been tested in the glassy and glassceramics obtained.

desde su fundación no sólo ha realizado a lo largo de su ya larga historia investigaciones y vali... more desde su fundación no sólo ha realizado a lo largo de su ya larga historia investigaciones y valiosas aportaciones científicas y técnicas en el campo de los materiales cerámicos y vidrios, sino que además fue uno de los principales fundadores de la actual Sociedad Española de Cerámica y Vidrio (SECV) con la destacada participación de D. Francisco Arredondo y Verdú. En los últimos once años esta línea de investigación se ha visto reforzada con la creación del Grupo y Laboratorio de Materiales Vítreos y Cerámicos, por lo que se realiza una revisión de la relación de este centro con este tipo de materiales, recordándose los investigadores y publicaciones que más destacaron en este camp. Se realiza finalmente un análisis de la situación actual y de las perspectivas de I+D+i en este tipo de materiales de construcción, haciendo especial énfasis en sus aplicaciones en fachadas ventiladas y del factor dinamizador de la investigación científica que implicará el reto tecnológico de la aplicación de plaquetas cerámicas en este tipo de fachadas.

Ceramics International, 2013

This work presents the results of a study focused on the development of forsterite-nepheline glas... more This work presents the results of a study focused on the development of forsterite-nepheline glass-ceramic with the use of rice husk ash (RHA) as a silica source. The glass-ceramics were produced by a sintering process of a glassy frit formulated in the MgO-Al 2 O 3-SiO 2 base system with the addition of B 2 O 3 and Na 2 O to facilitate the melting and pouring processes. The crystallisation study was carried out by depicting the TTT curve (Time-Temperature-Transformation). The mineralogical characterisation of the glass-ceramic materials was carried out using X-ray diffraction (XRD). The crystallisation activation energies were calculated by the Kissinger method. The results obtained show that devitrification of the RHA glass leads to a glass-ceramic material composed of nepheline (Na 2 O•Al 2 O 3 •2SiO 2) and forsterite (2MgO•SiO 2). A study of the microstructure by scanning electron microscopy (SEM) allowed to establish the morphological evolution in both the shape and spatial arrangement of the nepheline and forsterite crystals on heating.

Ceramics International, 2013

Technological properties of glass-ceramic tiles obtained using rice husk ash as silica precursor.

Journal of Analytical and Applied Pyrolysis, 2012

Thermolysis of fibreglass polyester composite and reutilisation of the glass fibre residue to obt... more Thermolysis of fibreglass polyester composite and reutilisation of the glass fibre residue to obtain a glass-ceramic material.

La presente invención se refiere a un método para preparar fritas de vidrio suministrando la ener... more La presente invención se refiere a un método para preparar fritas de vidrio suministrando la energía total requerida en el proceso por medio de radiación solar concentrada.Se relaciona además con un dispositivo para llevar a cabo dicho método que comprende elementos tales como un espejo plano solar, un obturador del haz de luz solar y un concentrador de radiación solar El dispositivo incluye además medios para almacenar, alimentar y contener las materias primas. Se derivan varias ventajas del uso del método y dispositivo de la presente invención, que se pueden resumir en una reducción en el consumo de energía y en un aumento de la productividad del procesoPeer reviewedConsejo Superior de Investigaciones Científicas (España)B2 Patente con examen previ

Materials

Lightweight aggregates are extensively used in construction and other industrial applications due... more Lightweight aggregates are extensively used in construction and other industrial applications due to their technological characteristics. The extraction of natural aggregates results in serious environmental effects. Thus, within the circular economy concept, the valorization of waste through the optimization of materials and product design is encouraged. In this work, glass lightweight aggregates were prepared from mixtures of white glass cullet and carbonate wastes from mining (wastes originating from the extraction, manufacture and marketing of magnesite and its derivatives) and the food industry (eggshell and mussel shell). The effects of different processing parameters, such as the particle size of the base glass, percentage of the blowing additive, shaping method, heating rate, temperature and processing time, were evaluated. The results indicate that the mineralogical composition of the blowing agent and the particle size of the base glass are the two processing parameters wi...