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Se reporta por primera vez la preparación del catalizador tipo arcilla pilarizada con Al/Fe en una escala de 10 kg a partir de precursores en medio concentrado y se evaluó su eficiencia catalítica en la reacción de peroxidación catalítica en fase húmeda (PCFH) de fenol. En primer lugar, para llevar a cabo el escalamiento se identificó mediante el estudio de cuatro arcillas de origen colombiano (C1, C2, C3 y BV), que el material C2 mostró el mayor potencial como mineral de partida en la preparación del catalizador Al/Fe-PILC ya que presentó el mejor rendimiento catalítico en la PCFH de naranja de metilo (decolorización ~ 70 % y eliminación de carbono orgánico total ~ 50 %) en función de las importantes propiedades fisicoquímicas tanto del material de partida como del pilarizado. En segundo lugar, se optimizaron las condiciones de preparación de una disolución intercalante concentrada, empleando una metodología alternativa usando aluminio elemental, mediante la cual se preparó una disolución intercalante con una concentración total de metales cercana a 5,0 mol/L. El catalizador preparado presentó un elevado rendimiento catalítico en la reacción PCFH de fenol (conversión de fenol del 92 % en 135 min de reacción y mineralización de COT equivalente al 45 % en 210 min de reacción). En tercer lugar, se evaluaron tres modos de intercalación, los cuales se diferenciaron por la presencia y ausencia de un medio de dispersión (etanol/agua/sin medio de dispersión); en éste caso, se encontró que la intercalación en ausencia de medio de dispersión fue la estrategia más apropiada ya que el aluminosilicato intercalado/pilarizado a escala de laboratorio exhibió propiedades fisicoquímicas (alta incorporación de Al y Fe; d001 ~ 17,0 Å; SBET ~ 100 m2/g y la presencia de verdaderos pilares mixtos de Al/Fe estabilizados en el espacio interlaminar) comparables con las obtenidas mediante el método preparación estándar a partir de precursores muy diluidos. Finalmente, al preparar el catalizador a 10 kg se encontró que las propiedades fisicoquímicas que resultaron principalmente afectadas fueron la expansión del espaciado basal y las propiedades texturales. Abstract: For the first time, the preparation of the pillared clay based catalyst with Al/Fe at 10 kg scale from precursors in concentrated medium is reported and its catalytic efficiency was evaluated in the catalytic wet phase peroxidation reaction (CWPO) of phenol. For the first time, the Al/Fe PILC catalyst was prepared at 10 kg scale in concentrated medium and its catalytic efficiency was evaluated in the catalytic wet phase peroxidation reaction (CWPO) of phenol. First of all, it to carry out the scaling up, it was identified by studying four clays of Colombian origin (C1, C2, C3 and BV), that the C2 material showed the greatest potential as starting mineral in the preparation of the Al/Fe PILC catalyst since it presented the best catalytic performance in the CWPO of methyl orange (decolourization ~ 70 % and eliminate total organic carbon ~ 50 %) in function of the important physicochemical properties of both the starting material and the pillaring. Secondly, the conditions for the preparation of a concentrated interlayering solution were optimized, using an alternative methodology indirect hydrolysis with elemental aluminum, by means of which an interlayering solution was prepared with a total metal concentration of ~ 5.0 mol/L. The catalyst prepared had a high catalytic performance in the PCFH reaction of phenol (phenol conversion of 92 % in 135 min of reaction and mineralization of TOC equivalent to 45 % in 135 min of reaction). Thirdly, three modes of interlayering were evaluated, which were differentiated by the presence and absence of dispersion medium (ethanol/water/without dispersion medium); in this case it was found that the interlayering in the absence of dispersion medium was the most appropriate strategy since the interlayered/pillared aluminosilicate at laboratory scale exhibited physicochemical properties (high incorporation of Al and Fe; d001~ 17.0 Å; SBET ~ 100 m2/g and the presence of true mixed Al/Fe pillars stabilized in the interlayering space) comparable with those obtained by the standard preparation method from highly diluted precursors. Finally, when the catalyst at 10 kg was prepared, it was found that the physicochemical properties that were mainly affected were the expansion of the basal spacing and the textural properties. Maestría

Findings in a total of 84 research papers identifying clay minerals on 520 soil samples of Costa Rica are summarized. This review emphasizes on the clay minerals described in the topsoil samples, although clay minerals in the B horizons are also discussed when they are different to predominant mineralogy in the topsoil. Sites where soil clays information is available were geo-referenced, to observe their geographical distribution. In general most of the country possesses soil clays identified, except for the Nicoya Peninsula, the Northern Zone, and the Eastern Talamanca Range. Clay mineralogy suites (“predominant clay groups”) were grouped as: (1) vitrous-amorphous-halloysitic (Andisols and other soils with andic properties; (2) smectites and interstratified clays (Vertisols and other soils with vertic properties); (3) oxides- hidroxides-oxihidroxides-kaolinite-gibbsite (Alfisols, Ultisols and Oxisols); Plus a large area of soils with mixed clay mineralogy, found in places with little or no development (Entisols and Inceptisols). The soil clay genesis of the main clay types in the country is discussed when enough information was available. Se resume la información disponible sobre caracterización de arcillas en suelos de Costa Rica desde 1931 hasta el presente, descrita en 84 trabajos con 520 observaciones hasta el 2014. La discusión se basa principalmente en la mineralo- gía de arcilla de los horizontes superficiales del suelo, aunque se menciona la mineralogía de los horizontes B cuando ésta es diferente a la de los horizontes A de manera relevante. Después de ubicar los datos puntuales en un mapa del país, se encontró que algunas áreas cuentan con poca o ninguna información (península de Nicoya, Zona Norte y región este de la Cordillera de Talamanca). Para el área restante la información disponible se agrupó por mineralogías de “arcilla dominante”, identificándose las mineralogías: (1) vidrio-amorfo-halloysítica (Andisoles y otros suelos con características ándicas); (2) esmectítica y de arcillas interestratificadas (Vertisoles y otros suelos con características vérticas); (3) óxidos-hidróxidos-oxihidróxidos-caolinita-gibbsita (Alfisoles, Ultisoles y Oxisoles); además de una serie importante de mineralogías mixtas en suelos de poco o ningún desarrollo edáfico (Entisoles e Inceptisoles). En el texto se discute la génesis (procesos de formación) de los principales tipos de arcilla del país, cuando se contó con suficiente información para ello.

Se resume la información disponible sobre la mineralogía de arcilla de los horizontes superficiales del suelo, aunque se menciona la mineralogía de los horizontes B cuando esta es diferente a la de los horizontes A, de manera relevante, en suelos de Costa Rica desde 1931hasta el presente. Se enfatiza en la información disponible para (1) esmectíticas y de arcillas interestratificadas en Vertisoles y otros suelos con características vérticas y (2) óxidos-hidróxidos oxihidróxidos-caolinita-gibbsita en Alfisoles Ultisoles y Oxisoles. En el texto se discute la génesis (procesos de formación) de estos grupos dominantes de arcilla cuando se dispone de suficiente información. This paper summarizes available information on soil clay mineralogy in topsoils of Costa Rica, including clay minerals described in B horizons when significantly different from predominant mineralogy in the topsoil. The soil clay suites (“predominant clay groups”) emphasized are grouped as: (1) smectites and interstratified clays (Vertisols and other soils with vertic properties), and (2) oxides-hidroxides oxihidroxides-kaolinite-gibbsite (in Alfisols, Ultisols and Oxisols). The soil clay genesis of these dominant groups is discussed when enough information is available.

En este trabajo se presentan los resultados de la caracterización mineralógica de las esmectitas representativas de la zona saprolítica y esmectítica del perfil de San Felipe mediante análisis de Difracción de rayos X (DRX) tanto de muestras en polvo como de agregados orientados (AO, AO+EG, AO+550ºC) y Microscopia Electrónica de Barrido (SEM-EDS) y de Transmisión (TEM-AEM).

2 páginas.-- Comunicación presentada en la XXIX Reunión de la Sociedad Española de Mineralogía, celebrada en Salamanca entre el 9 y 12 de Septiembre de 2009., La cuenca de St. Mary (Nueva Escocia, Canadá) se desarrolló a lo largo de una zona de falla en la sutura entre los terrenos de Avalonia y Meguma. Su génesis está influenciada por un movimiento dextro durante el Devónico superior-Carbonífero, que se ha atribuido a la rotación en el sentido de las agujas del reloj de Laurentia respecto a Gondwana (Keppie et al., 1996). En la actualidad está constituida casi en su totalidad por materiales clásticos de origen continental correspondientes al Devónico superior-Carbonífero inferior., Trabajo financiado por los grupos RNM- 325 y RNM-179 de la Junta de Andalucía y los proyectos CGL2007- 66744 y CGL2006-00902 (O.D.R.E.) del Ministerio de Ciencia y Tecnología.

Se modificó una esmectita natural con soluciones mixtas de Al-Ce en presencia de un tensoactivo de tipo no iónico (óxido de polietileno). La intercalación se llevó a cabo asistida por ultrasonido para favorecer la homogenización de la mezcla y la difusión de especies hacia la interlámina del mineral. Se estudió el efecto de la relación tensoactivo-arcilla y la potencialidad de estos materiales como soportes catalíticos para el níquel. Los análisis termogravimétricos indicaron que la descomposición del tensoactivo se da a 500 °C. Los espectros DRIFT y DRX sugieren que la incorporación del tensoactivo se presenta en la superficie externa del mineral, el cual fue pilarizado. El aumento en la cantidad de tensoactivo causó pérdida de cristalinidad del material. La presencia del tensoactivo induce la formación de mesoporos. Los TPR-H2 indicaron que la modificación en presencia del tensoactivo favorece la reducibilidad del Fe del mineral. Se identificaron diferentes especies reducibles de Ni sobre la superficie del soporte, evidenciándose un aumento en la interacción níquel-soporte y en la reducibilidad a 700 °C con H2 puro para los catalizadores obtenidos a partir de los materiales modificados con tensoactivo. Se obtuvieron catalizadores con buena distribución del níquel en la superficie, tamaños de cristalitos menores de 10 nm y estabilidad térmica limitada. Los catalizadores modificados con tensoactivos soportados sobre arcillas presentaron mejores actividades catalíticas en el reformado de metano con CO2 a 700 °C (WHSV =60Lg-1h-1) con menores niveles de formación de coque. A natural smectite was modified with Al-Ce solutions in the presence of Non-ionic surfactant (polyethilene oxide). The intercalation was carryingoutby ultrasound assistance in order to promote homogenization of the slurry and the diffusion of species into the lamellar space of mineral clay. The effect of surfactant-clay ratio and the potential of these solids like nickel catalytic supports were investigated. Thermogravimetical analysis indicated that the surfactant decomposition it is completed at 500 °C. DRIFT and XRD spectra suggest that the incorporation of the surfactant is on the external surface of clay and that the mineral was pillared. The increase in the surfactant ratio causes a lose of cristallinity material. The presence of surfactant induced mesoporous formation in the material. TPR-H2 indicated that the modification in presence of surfactant promotes the reducibility of Fe in the mineral. Several Ni reducible species on the support surface were identified. The interaction Ni-support and the reducibility with pure H2 at 700 °C were increased when the mineral clay was modified with the surfactant. Catalysts with good nickel distribution, particle size under 10nm and thermal stability limited was obtained. Ni-Catalyst supported on surfactant modified clays showed the best catalytic performance in the CO2 reforming of methane at 700 °C (WHSV =60Lg-1h-1) whit the lowest coke formation. Uma esmectita natural foi modificada pelo meio de uma mistura com uma solução de Al-Ce, na presença de um surfactante do tipo nonionic (óxido de polietileno). A intercalação foi realizada assistida por ultra-som para facilitar a homogeneização da mistura e da difusão das espécies no espaço interlamelar da argila mineral. Nós estudamos o efeito do peso argila-surfactante e as potencialidades destes materiais como suporte para os catalisadores do níquel. A análise termogravimétrica indicou que a decomposição da superfície é completa a 500 °C. Espectros DRIFT e DRX sugerem que a incorporação do surfactante ocorre preferencialmente na superfície externa da argila e que foi modificada pelo meio dum processo do pilarização. O aumento da quantidade de surfactante provoca uma perda de cristalinidade do material. A presença da surfactante induziu a formação do mesoporous no material. O TPR-H2 mostrou que a mudança na presença do surfactante favorece a redução do Fe neste mineral. Também foi possível a identificação de uma formação de espécies reduzíveis do níquel na superfície do meio que. Encontraram-se um aumento do níquel-suporte a interação e reducibilidad em 700 °C com H2 puro para os catalisadores feitos de materiais com superfície modificada. Catalisadores foram obtidos com boa distribuição de níquel na superfície, e tamanho do cristal menores de 10nm e estabilidade térmica limitada. O catalisador suportado em argila modificada com surfactante mostrou melhor atividade catalítica na reforma do metano a 700 °C (WHSV =60Lg-1h-1) com baios níveis de formação de coque.

Cinco materiales arcillosos provenientes del departamento del Tolima (Colombia), fueron caracterizados mineralógica, química y granulométricamente. Los resultados indican que los materiales contienen diferentes proporciones de fase esmectítica dioctaédrica (entre 24 y 64%), con comportamiento similar al de la montmorillonita tipo "chambers", excepto en un caso donde se confirma la presencia adicional de montmorillonita de transformación. El análisis mineralógico reveló tres casos, un grupo de sólidos con presencia de una fase esmectítica bien definida que no presenta interacciones con otras estructuras; otro caso, donde se detectaron dos tipos de esmectitas que difieren en su origen y, finalmente, materiales con la presencia de interestratificación. Five clay minerals from Tolima (Colombia) were mineralogical, chemical and granulometrical characterized. The results showed that the materials have different contents of dioctahedral smectite (24 64%) similar to chambers type montmorillonite, except in one case where is evident the additional presence of transformed montmorillonite. Through the mineralogical analysis were established three cases. For the first case, there was a smectitic phase; in second place, the material present two types of smectitic phases whereas a third sample showed the presence of interstratifications.

Los suelos zonales de la Pampa Ondulada son Argiudoles Típicos y Vérticos los cuales se diferencian en la composición mineralógica de su fracción arcilla. El objetivo del presente trabajo fue analizar las vinculaciones entre la tasa de movimiento del agua edáfica con algunos atributos relacionados con la composición mineralógica de la fracción arcilla, en distintos suelos representativos de la región mencionada. Se tomaron muestras de los horizontes A, BA/BE, Bt y BC de dos Argiudoles Típicos y de un Argiudol Vértico, realizando sobre las mismas determinaciones relacionadas con la cantidad y tipo de las arcillas presentes. A su vez mediante diferentes técnicas se evaluaron el sistema poroso del suelo y el movimiento de agua edáfica. En los horizontes Bt, aquellos parámetros que integran el tipo y el contenido de arcillas, como el COLE y la CIC, mostraron estar mejor vinculados con el movimiento de agua edáfica que cuando se consideró únicamente el porcentaje de arcilla. La distinta porosidad estructural generada dentro de los agregados de los horizontes Bt, originó diferencias en su difusividad y conductividad hidráulica no saturada, a contenidos de humedad por encima del 50% de saturación. En aquellos horizontes con mayor actividad biológica y menor contenido de arcilla, el movimiento de agua se realizó en forma independiente de las características de las arcillas presentes. Typic and Vertic Argiudolls, which differ in the composition of their clay fraction, are the zonal soils in the Rolling Pampa of Argentina. The aim of this work has been to analize the relationship between water movement and diverse soil properties in some representative soils of the Rolling Pampa, differing in their clay mineralogy. The A, BA/ BE, Bt and BC horizons of two Typic and one Vertic Argiudolls were sampled and a number of properties related with clay content and clay type were measured. Soil porosity and soil water movement were also evaluated through different techniques. In the Bt horizons, those parameters integrating clay type together with clay content, as COLE and CEC, have shown a better relationship with soil water movement than considering clay quantity alone. Clods from Bt horizons of studied soils have shown to differ in their internal structural porosity and this led to different diffusivity and unsaturated (at 50% water holding capacity) hydraulic conductivity results. In upper soil horizons, characterized by a lower clay content and a greater biological activity, water movement was not related to clay mineralogy.

The research during the construction of the M-50 highway has allowed the study of the silica levels that constitute the most important Neolithic flint mine in the Iberian Peninsula. A group of more than 3.800 extraction pits were realized to obtain cherts and opals that appear among Mg smectites beds (Aragonian deposits). The description of the nodular and stratiform silica levels and the study of their types and distribution have been done at geological sections obtained during the archaeological excavations. Three petrological types of siliceous rocks (chert, opal and opaline chert) are established and defined according to their mineralogy and microfacies. Cherts are constituted only by quartz and locally minor amounts of moganite. Opals contain opal CT, Mg smectites and minor quartz. Opaline chert is defined when the proportion of quartz is higher than 50%. All the types of siliceous rocks reproduce bioturbation structures as well as other structures found in the host rocks (grains, intraclasts, brecciation). The silica levels at the base of the columns are constituted only by chert and were formed by the silicification of nodular and lenticular dolomite levels included in the Mg-smectites beds. The rest of the siliceous levels are composed of opals and opaline cherts and were formed by silicification of Mg-smectites. The outer part of the opaline chert has a higher content in opal and clay relicts whereas the inner part is mainly microcrystalline quartz. This change is consequence of the recrystallization of the opal (aging) producing a more compact silica rock. The main silicification occurred under the groundwater table because the structure of the host rocks is conserved in the silica rocks. A general question is whether the silica that precipites is introduced by groundwater or it is released from the dissolution of clays during their replacement

The research during the construction of the M-50 highway has allowed the study of the silica levels that constitute the most important Neolithic flint mine in the Iberian Peninsula. A group of more than 3.800 extraction pits were realized to obtain cherts and opals that appear among Mg smectites beds (Aragonian deposits). The description of the nodular and stratiform silica levels and the study of their types and distribution have been done at geological sections obtained during the archaeological excavations. Three petrological types of siliceous rocks (chert, opal and opaline chert) are established and defined according to their mineralogy and microfacies. Cherts are constituted only by quartz and locally minor amounts of moganite. Opals contain opal CT, Mg smectites and minor quartz. Opaline chert is defined when the proportion of quartz is higher than 50%. All the types of siliceous rocks reproduce bioturbation structures as well as other structures found in the host rocks (grains, intraclasts, brecciation). The silica levels at the base of the columns are constituted only by chert and were formed by the silicification of nodular and lenticular dolomite levels included in the Mg-smectites beds. The rest of the siliceous levels are composed of opals and opaline cherts and were formed by silicification of Mg-smectites. The outer part of the opaline chert has a higher content in opal and clay relicts whereas the inner part is mainly microcrystalline quartz. This change is consequence of the recrystallization of the opal (aging) producing a more compact silica rock. The main silicification occurred under the groundwater table because the structure of the host rocks is conserved in the silica rocks. A general question is whether the silica that precipites is introduced by groundwater or it is released from the dissolution of clays during their replacement

The igneous massif of Benavila (Portugal) is constituted by rocks of granitoid nature, especially granodiorites associated to quartzdiorites, partially covered with palaeogenic sediments. A chemical, mineralógicaI and textural characterisation of clay materials deriving from weathering of those rocks has been done. Clays resulting of the weathered granodiorites of Benavila, are very rich in smectites. The X-ray diffraction (XRD) results of the bulk sample enhance the clayey characteristics of those materials, mainly associated to calcite, and traces of quartz and feldspars. A monomineralic clay sample has been chosen for a more detailed study. The clay fraction XRD results enhance the presence of only smectite, that is well crystallized and dioctahedral. A structural formula for this smectite of Benavila is proposed. The chemical analysis points to a Tatatila smectite type, relatively enriched in iron. The exchange cation capacity has been calculated in the bulk sample and in the < 2 pm fraction. The Specific Surface area has been evaluated in the 77°K nitrogen adsorption-desorption isotherms, applying the BET method. A porosity study has also been made through the t-curves. The results obtained with all those analyses are lower than the usually presented in literature

The igneous massif of Benavila (Portugal) is constituted by rocks of granitoid nature, especially granodiorites associated to quartzdiorites, partially covered with palaeogenic sediments. A chemical, mineralógicaI and textural characterisation of clay materials deriving from weathering of those rocks has been done. Clays resulting of the weathered granodiorites of Benavila, are very rich in smectites. The X-ray diffraction (XRD) results of the bulk sample enhance the clayey characteristics of those materials, mainly associated to calcite, and traces of quartz and feldspars. A monomineralic clay sample has been chosen for a more detailed study. The clay fraction XRD results enhance the presence of only smectite, that is well crystallized and dioctahedral. A structural formula for this smectite of Benavila is proposed. The chemical analysis points to a Tatatila smectite type, relatively enriched in iron. The exchange cation capacity has been calculated in the bulk sample and in the < 2 pm fraction. The Specific Surface area has been evaluated in the 77°K nitrogen adsorption-desorption isotherms, applying the BET method. A porosity study has also been made through the t-curves. The results obtained with all those analyses are lower than the usually presented in literature

Clay minerals from the volcaniclastic deposits of the three different sedimentary settings (paleosols, continental lacustrine and transitional, fan delta) have been studied by X-ray, MEB y TEM. The clay fraction of this sediments consist largely of smectite (saponite) with minor irregular chlorite-smectite mixed layers and illite; they occur as replacement of ferromagnesian minerals, plagioclase microlites and glass matrix of the volcarenite and they are inferred to be direct diagenetic alteration products of volcanic components

Clay mineralogy Is controlled in the Campo de Gibraltar flyschs by some paleoenvironmental and dlagenetic factors, which appear differently reflected in the several units and lithologies. In fine-grained beds, clay minerals are mainly detrltal in origin and, consequently, they can be used as indicators of sources. In this work, the main detrital associations established from previous mineralogical and geochemical studies are described, and the influence of the possible sources is analysed. The obtained results confirm in some cases the previous interpretations, while in other cases led us to question either the proposed sources or the assumed paleogeographic relations between some of these units

The spatial distribution of clay minerals in the Cuestas Unit is described in this work. Cartographic distribution of the different minerals points towards a tectonic control of the genetic environments, resulting in NE-SW elongated bands. Kaolinite+chlorite and illite are located towards marginal areas of the Unit Palygorskite is concentrated in distal areas of a//uvial fans, derived from source areas located both to the NW and from the Honrubia basement area. Sepiolite and smectite concentrations are associated with evaporitic lacustrine basins, mainly located close to the Honrubia Massif

The spatial distribution of clay minerals in the Cuestas Unit is described in this work. Cartographic distribution of the different minerals points towards a tectonic control of the genetic environments, resulting in NE-SW elongated bands. Kaolinite+chlorite and illite are located towards marginal areas of the Unit Palygorskite is concentrated in distal areas of a//uvial fans, derived from source areas located both to the NW and from the Honrubia basement area. Sepiolite and smectite concentrations are associated with evaporitic lacustrine basins, mainly located close to the Honrubia Massif, En este trabajo se describe la distribución de arcillas en la Unidad de Cuestas. La distribución cartográfica de los distintos minerales sugiere un control tectónico de los ambientes genéticos, resultando en bandas anchas de dirección NE-SW. La caolinita+clorita y la illita se encuentran en las áreas del margen de la Unidad, y paligorskita en áreas distales de abanicos aluviales, derivada de fuentes en el NW y en el basamento de la zona de Honrubia. Las concentraciones de sepiolita y esmectita se asocian a cuencas lacustres evaporíticas , principalmente situadas cerca del macizo de Honrubia.