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[ES] El programa "Rutas científicas" pretende contribuir al fomento de la ciencia y la tecnología entre los jóvenes. responde a un objetivo de interés general como es alentar la reflexión científica sobre los problemas medioambientales y favorecer el conocimiento y aprecio de la riqueza natural y cultural de las distintas Comunidades Autónomas

[EN] The paper describes the setting up, history and working of the International Organization for Standardization (ISO), heiress of the extinct International Federation of the National Standardizing Associations (ISA), this latter born in 1926. After giving some general considerations about the ISO, the ISO/TC 27, the Technical Committee engaged in solid fuels, is treated in more detail. The activities developed by the four General Meetings celebrated the years 1950, 1951, 1953 and 1955 by thisCommittee, are shortly summarized. A second part of this work to come will inform about the present stage got over the matters that were treated, and the situation of the different international standards just at the moment the last meeting finished, which took place in Stockholm., [ES] Se describe la creación, historia y funcionamiento de la Organización Internacional de Normalización (ISO), descendiente de la Federación Internacional de Asociaciones Nacionales de Normalización (ISA), nacida esta última en el año 1926. Después de unas generalidades de conjunto, se trata con más detalle del ISO/TC 27, Comité Técnico que se ocupa de los combustibles sólidos. A continuación, se resumen brevemente las actividades que tuvieron lugar en las cuatro asambleas que ha celebrado dicho Comité, en 1950,1951, 1953 Y1955. En una segunda parte de este artículo, se dará cuenta del estado actual en que se encuentran los temas tratados y de la situación de las distintas normas internacionales a la terminación de la última de dichas reuniones, que tuvo lugar en Estocolmo.

[EN] The essential part of the report rendered by the Instituto Nacional del Carbon, on request of the Spanish Ministry of Industry, is transcribed. This served to state the formula fixing the price for siderurgical coke, according to its mechanical resistance and ash content. Related to the original price of a coke containing 20 per cent of ash and having a “solidity” lower than 60, a valuation is made in the report on the price that the Steel Industry is able to pay for cokes destinated to blast furnaces, with an ash content lower than 16 per cent and a solidity superior to the limit stated above. It is described, as a complement, the way to determine the value of «solidity» in the Micum drum, and suggestions are given in order to determine the ash and moisture contents, starting from the analysis coke sample., [ES] Se transcribe la parte fundamental del informe emitido por el Instituto Nacional del Carbon, a petición del Ministerio de Industria, que sirvió para el establecimiento de la fórmula que fija el precio oficial del coque siderúrgico, en función de su resistencia mecánica y de su contenido en cenizas. En el informe se valora, en función del precio original de un coque con el 20 % de cenizas y una solidez inferior a 60, el precio que puede pagar la industria siderurgia por coques destinados a homo alto, con 16 % 0 menos de cenizas y solidez igual 0 superior al limite indicado. Como complemento, se describe la forma como se determina el valor de la solidez en el trómel Micum, y se dan indicaciones sobre las normas seguidas en el Instituto Nacional del Carbón para las determinaciones de cenizas y de humedad partiendo de la muestra para análisis del coque.

[EN] The setting up, history and working of the ISO/Technical Committee 27 - Solid mineral fuels, of the International Organization for Standardization, had been dealt with in a previous paper. Now the present position (up to September the 30th 1956 of the studies for the setting up of International Standards is described. The questions successively dealt with are: sampling, total moisture, moisture in the analysis sample, moisture holding capacity, ash, volatile matter, calorific value, crucible swelling number, Audibert-Arnu dilatometer test, Gray-King test, Roga index, agglutinating value, carbon and hydrogen, nitrogen, total sulphur, forms of sulphur, oxygen; phosphorus, chlOrine, arsenic, mineral matter, ash fusion temperature, reporting of coal analysis results, washing terminolgy, methods for coke analysis and test, and tar content of brown coals and lignites., [ES] Descritos en un artículo anterior la creación, historia y funcionamiento del Comité Técnico ISOITC 27 «Combustibles minerales sólidos», de la Organización Internacional de Normalización (ISO), se expone en el presente trabajo el estado (referido al 30 de septiembre último) de las normas internacionales en estudio por dicho Comité. Los temas tratados sucesivamente son: toma de muestras, humedad total, humedad en la muestra para análisis, capacidad de humectación, cenizas, materias volátiles, potencia calorífica, hinchamiento al crisol, ensayo Audibert-Arnu, ensayo Gray-King, índice Roga, valor aglutinante, carbono e hidrógeno, nitrógeno, azufre total, formas de azufre, oxígeno/ fósforo, cloro, arsénico, materia mineral, temperatura de fusión de las cenizas, expresión de los resultados de los análisis del carbón, terminología de la técnica del lavado, métodos para análisis y ensayos del coque, y contenido en alquitrán de los carbones pardos y lignitos.

A series of nanoporous carbons was obtained by physical activation of polyethylene terephthalate and investigated for the separation of CO2 from flue gas. The prepared carbons exhibited extremely low functionalization—negligible content in oxygen and other heteroatoms—accompanied by well-developed porous networks consisting of gradually increasing surface areas and micropore volumes. Such features allowed to study the role of nanopore confinement in the separation of carbon dioxide in CO2/N2 gas mixtures. The analysis of the adsorption isotherms of individual gases and their mixtures revealed different trends for the CO2 uptake and the selectivity. Whereas CO2 uptake was larger in the carbons with higher burn-off degree, the selectivity of CO2 over N2 was favored in the carbons with a higher fraction of narrow micropores. The differential adsorption enthalpy curves are typical of highly microporous samples reaching values close to those found in zeolites for low loadings. Data also show that the choice of the best adsorbent for cyclic gas adsorption and separation processes should consider a broad context, taking into account various parameters simultaneously such as gas selectivity, working capacity, adsorption enthalpy and energy consumption in the synthesis of the adsorbent.

The photocatalytic activity of a series of novel KSrNbO materials was studied using the photooxidation of methylene blue as model reaction. The influence of the calcination time upon the crystalline structure and photoactivity was verified. Characterization was performed by XRD, SEM, FTIR, UV–Vis/DR, Helium picnometry, and N and CO adsorption-desorption isotherms. The diffraction line profile and the refinement of the structural parameters of KSrNbO were obtained from the XRD patterns by the Rietveld method. Data showed that samples were photoactive under UV irradiation, regardless the synthesis conditions. However, the calcination time had a clear influence upon the photocatalytic activity of the samples, being more efficient towards the degradation of the dye those obtained at a lower calcination time. Indeed, the sample calcined for 4 h showed up to 4 times higher photocatalytic activity than commercial TiO. Additionally, a correlation between the photocatalytic activity and the displacement of the Nb ion from the central position in the [NbO] octahedron was found. It is suggested that this fact causes an important polarization of the niobate structure. The apical oxygen in these samples is very reactive and can lead to the formation of superoxoradical anions (O ) showing that KSrNbO can be potentially used in photocatalytic reactions under UV irradiation., J. Matos thanks to the Chilean grants (Basal ProgramPFB-27, FAE-829, FONDEF-IDEA #ID15I10321, CORFO15IPPID-45676, FONDECYT1161068), for their financial support. S. Lanfredi thanks FAPESP (grants 2007/03510-9, 2014/11189-0, CNPq and UNESP/PROPe), for their financial support. C.O. Ania thanks the financial support of the Spanish MINECO (grant CTM2011/56770-R).

In this work, the characterization of the non-covalently bonded compounds present in a set of perhydrous coals of different age and geographical location (Cretaceous coals: UCV and TCV and Jurassic coals: AJV, PGJV, WJVh and WJVl) was carried out by means of a combination of the analyses of the material soluble in chloroform and the thermal extract. The extract in chloroform was studied through GC/MS and NMR and the thermovaporized fraction was obtained by means of flash pyrolysis at the Curie temperature of 350°C and quantified by on-line GC-MS. The results obtained for the Cretaceous coals confirm that the substances responsible for the hydrogenation are those covalently bonded to the vitrinite network as a result of the modifications undergone by the botanical precursors. Despite the striking similarity in the global characteristics of these two coals (TCV and UCV) significant differences between the material non-covalently bonded to their coal matrices were found. These differences are attributed to the type of resins present in the coals and/or to their different degree of evolution. With respect to the Jurassic coals, the present study allows the process by which the hydrogenated substances were assimilated into their structure to be established. The characterization of the assimilated substances in the WJVl coal reveals an unexpectedly high incorporation of alkanes given the humic origin of this sample. From these results the assimilation of hydrogen-rich substances from the decomposition of the organic remains in the sedimentary environment in which WJVl precursor were deposited, is proposed. The incorporation of products derived from the primary decomposition of organic material is not evident for the WJVh and AJV coals. The substances assimilated into the coal matrices show a higher aromaticity, the aromatic structures of WJVh being more condensed than those found in AJV. The compositional differences between them probably arise from the different source of the hydrogen-rich material. In the case of AJV coal the source was the adsorption of hydrocarbons generated and migrated from the Pliensbachian source-rocks whereas in WJVh, assimilated compounds come from the material generated by the thermal transformation (coalification) of the adjacent organic rocks of similar age. Finally, PGJV shows two types of non-covalently bonded compounds. Solvent extractable material is mainly composed of the first type of compounds, which is predominantly aliphatic in nature with a preponderance of alkanes. The second type of compounds is more aromatic and they are probably located in the close porosity of this coal. They are not accessible to chloroform but they are the most abundant in the thermal extract., The financial support for this work was provided through a contract with the European Community (No. 7220/EC-769).

A study of coal products obtained from Gray-King pyrolysis at 550 °C was carried out in order to obtain information about the chemical modifications of the huminite/vitrinite structure resulting from different processes of natural hydrogen-enrichment. The high oil yield obtained, the similarity between the infrared spectra of the generated oils and those of the parent vitrinite as well as the parallelism between the compositional data deduced for these oils and those obtained by means of Curie point pyrolysis-gas chromatography/mass spectrometry justify the use of this thermal approach. Gray-King pyrolysis is preferable to other techniques because it is possible to make an accurate mass balance, a thorough study of the solid residues and a full characterization of both the volatile and non-volatile fractions of the degradation products. From a study of selected perhydrous coals, mainly composed of the vitrinite maceral group, only in the low reflectance Jurassic coal from the Whitby (England) basin (WJVl) was the incorporation of lipoidal material evident, due to the significant contribution of long-chain alkyl aromatics in its oil. The structure of the vitrinite in the other Jurassic coals, the high reflectance sample from the Whitby basin (WJVh) and the coals from the Asturias (Spain) and Portugal basins (AJV and PGJV, respectively), is probably similar to that described for non-perhydrous vitrinites in the subbituminous coal rank. However, the presence of assimilated hydrogenated substances of a secondary nature, in particular for AJV and PGJV, hinders the cross-linking and condensation processes typical of the transit to the bituminous coal rank. In Cretaceous coals, from Teruel (Spain) and Utah (EEUU), (TCV and UCV, respectively), whose perhydrous character is mainly due to the specific hydrogenated nature of their botanical precursors, the incorporation of aliphatic structures via covalent oxygen linkages is proposed. The results obtained may be useful for establishing accurate structural models for perhydrous vitrinites. At the same time, the data obtained will contribute to explain the involvement of the high hydrogen content in the suppression of vitrinite reflectance.

The vitrain from Teruel (North-Eastern Spain) is a good example of a vitrinite whose perhydrous character and anomalous properties are caused by the presence of terpene-type resin. The sample used in this work was isothermally pyrolysed in an open-medium system at temperatures ranging from 250 to 500 °C. A mass balance, a petrographic and geochemical characterisation of the pyrolysates and compositional and structural analyses (GC and NMR) of the generated oils were performed. The results confirm the association of huminite-resinous substances through covalent bonds and also point to the possible incorporation of aliphatic material via covalent oxygen bonds. The side-chains that serve as linkers between the phenolic subunits derived from the lignin contain more labile thermal bonds than those present in other vitrinites not affected by resin saturation. Consequently, this type of vitrinite undergoes a more intense degradation at lower temperatures than non-perhydrous and other hydrogen-rich vitrinites. The vitrinite network itself due to the incorporation of resin-like substances (cycloparaffinic in nature) may serve as a hydrogen donor, enhancing the hydrogenation processes during pyrolysis with respect to the polymerisation and recombination reactions. The higher ability of hydrogen to stabilise the free radicals formed during pyrolysis explains the higher conversion to liquids at lower temperatures than in the case of non-perhydrous vitrinites. At the same time, this ability limits the growth of the aromatic structures. The evolution of the vitrinite modified by the presence of terpene-type resin is, thus, retarded with respect to non-perhydrous vitrinites, although in both cases the trend followed is very close. In contrast the trend of this type of vitrinite differs considerably from that of perhydrous vitrinites which are affected by hydrocarbon impregnation. Only for the most severe treatments (450/500 °C) was some degree of structural uniformity observed in the solid residues.

International audience; Six widely differing, novel capture processes, currently under development in Europe are described. These processes cover the range of postcombustion, precombustion and denitrogenation and show favourable possibilities for integration with power plants. They can be regarded as potential break-throughs in technical performance and/or costs.

This work analyses a set of perhydrous coals (mainly composed of huminite/vitrinite maceral group) in order to determine the inter-relations between the hydrogen content and the modifications in the coal structure at a molecular level. The study involves the direct solid state characterisation of the coal combined with the analysis of representative fragments of the coal network obtained through flash-pyrolysis. The perhydrous character of the coals is not reflected either in the aliphatic hydrogen concentration (from FTIR data) or by the presence of straight-chain aliphatic moieties in the pyrolysates. This structural study shows that perhydrous coals contain mainly aromatic structures with 1–2 rings and a very small concentration of aromatic rings of large size. In agreement with this, phenol and alkyl phenols are the most prominent degradation products whereas other aromatic compounds (mainly benzene and naphthalene derivatives) are minor and probably evaporative compounds. The major structural elements in the samples studied are simple phenols with a preponderance of substituted para alkyl. The results obtained show that the processes of hydrogen enrichment affect the reactions of aromatisation and condensation. During the natural evolution of the perhydrous coals the transformations of the oxygenated functionalities in the lignin precursor seem to have taken place without the parallel structural reorganisation of the lignin framework responsible for the formation of polycyclic aromatic systems. As a result, the chemical structure of perhydrous vitrinites in coals is substantially modified with respect to that described in ‘normal' coals. The results obtained also indicate that the source of hydrogen content and the effect that it has during the subsequent evolution process of the coals, affects the chemical structure of the perhydrous vitrinite and hence its properties and behaviour., Financial support for this work was provided through a contract with the European Community (No. 7220/EC-769).

The present work analyses the changes in the chemical structure of a perhydrous coal during its thermal evolution at different temperatures in an open-medium pyrolysis system. The results obtained were compared with those described for non-perhydrous coals in order to establish the effect of the substances assimilated by the coal structure (hydrocarbon/oil-like substances) on the thermal evolution of the coal. The transformation ratio at each stage of thermal treatment was determined and the chemical-structural characterisation of the resultant products was performed. Changes in textural and microtextural properties associated with structural modifications during the evolution were also tested. The results obtained show that this perhydrous coal develops a specific evolution pathway different from that followed by non-perhydrous coals with a normal H/C ratio. The substances assimilated by the perhydrous coal cannot be easily and totally released from its structure so that they can be only partially removed after thermal treatment. Thus, the treatment debilitates the interactions between the substances and the coal matrix in addition to weakening and cracking the matrix during the thermal process. The increase in temperature also leads to the conversion of some of the heavy assimilated substances into lighter compounds. However, the assimilated substances are present even at high temperatures of the thermal process, providing hydrogen which has the effect of stabilising the radicals originated during the pyrolysis and improving the fluidity properties in the reacting medium., Financial support for this work was provided through a contract with the European Community (No. 7220/EC-769).

The electrochemical reduction of GO was investigated in aqueous, at both acid and basic pH, and organic media, to identify the possible role of protons (H+) in the reduction mechanism of this material. The obtained rGO films were characterized by FTIR, electrochemical methods, Raman and XPS spectroscopy. Data showed that the reduction was more efficient in acid and basic media due to the presence of protons and the capacity of water that works as a proton donor, resulting in C/O ratios of 3.8 and 7.8, respectively. Mostly hydroxyl, epoxide and carbonyl moieties were removed. In a proton-free organic electrolyte, a C/O ratio of 1.8 was obtained for most of the samples; nevertheless, the graphitic carbon sp2 domains were restored to a large extent in the absence of H+. The characterization of the material showed that the presence of protons, during the electrochemical reduction, caused hydrogenation reactions, which targeted the graphitic domains in rGO and resulted in the loss of sp2 hybridization. The presence of such defects modified the electrochemical properties of the rGO films, where, despite of exhibiting higher C/O ratio, the films reduced in aqueous electrolytes displayed lower electron transfer (e.g. ferrocyanide redox-probe) than those reduced in organic electrolyte.

This work provides new insights in the field of applied photoelectro chemistry based on the use of nanoporous carbons as additives to tungsten oxide for the photooxidation of water under potential bias. Using a nanoporous carbon of low surface functionalization as additive to WO3 we have shown the dependence of the photochemical oxidation of water with the wavelength of the irradiation source. Photoelectrochemical responses obtained under monochromatic illumination show a significant increase in the incident photon-to-current conversion efficiency (IPCE) values for electrodes featuring up to 20 wt% carbon additive. Photoelectrochemical transient responses also show a sharp potential dependence, suggesting that the performance of the electrodes is strongly influenced by the carrier mobility and recombination losses. Despite the modest IPCE values of the W/NC electrodes (due to high bulk recombination and poor electron transport properties of the electrodes), our data shows that the incorporation of an optimal amount of nanoporous carbon additive to WO3 can enhance the carrier mobility of the semiconductor, without promoting additional recombination pathways or shadowing of the photoactive oxide., COA thanks the financial support of the European Research Council through a Consolidator Grant (ERC-CoG-648161-PHOROSOL) and the Spanish MINECO (grants CTM2014/56770-R, CTQ2013-48280-C3-3-R). VC and DJF kindly thank the UK Catalysis Hub for resources and support provided via the membership of the UK Catalysis Hub Consortium and funded by EPSRC (grants EP/ K014706/1, EP/K014668/1, EP/K014854/1, EP/K014714/1 and EP/M013219/1). AGB thanks her PhD fellowship (BES-2012-060410) and VC thanks the UK National Academy and the Royal Society by the support though the Newton International Fellows program.