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This study explores the use of whey powder in Selective Laser Sintering (SLS) to create porous carbon parts. Whey powder, heated at 150°C, forms solid parts due to melanoidin formation from lactose and whey proteins. Carbonized whey parts maintain their shape with controlled shrinkage, allowing for precise printing with high porosity and mechanical strength. A video demonstrating the process, as well as STL files for printed artifacts, are provided.

Despite technological advances and increasing recognition of the nutritional benefits of whey, a significant portion remains underutilized, especially in small cheese factories. Additionally, the rising production of acid whey, generated from the manufacturing of Greek yogurt, presents a management challenge due to its more complex valorization compared to sweet whey

Carbon-based materials were tested as methanogenic boosters to enhance the anaerobic treatment slaughterhouse wastewater, which included an organic xerogel (OX) doped with graphene oxide, a peach stone carbon (PSC), and a monolithic whey carbon (MWC). Enhanced treatment by the carbon-based boosters was evident in terms of organic matter removal and methane production rate, which was globally reflected on a superior methanogenic conversion efficiency as compared to the unamended control. OX appeared as the best methanogenic booster increasing up to 77 % and 12 % the methane production rate and organic matter removal, respectively. The obtained results suggest that hydrolysis and acidification of the complex wastewater were the limiting steps during the treatment of this industrial effluent. This observation is consistent with the higher production of ammonium, derived from protein hydrolysis, which occurred in bioreactors amended with carbon-based materials, as compared to the unamended control. Several changes in the relative abundance of key microbial taxa occurred; particularly, members of the bacterial families Synergistaceae and Anaerolineaceae, as well as the archaeal Methanolinea and Proteiniclasticum genera, increased significantly in the presence of OX. The synthesized materials are proposed to improve the performance of anaerobic treatment systems dealing with complex wastewaters.

Novel customised carbon monoliths with a high specific surface area were synthesised by carbonisation plus activation of dehydrated whey powders, a biomass byproduct of the dairy industry. The whey powders were casted directly by pouring them into a desired mould. After a pseudo-sintering process promoted by the self-reaction of the whey components (mostly lactose and whey proteins) at moderate temperatures (ca. 250 °C), 3D porous carbons were obtained. The process did not require any binder or external overpressure to prepare the 3D porous carbons. Upon thermal activation with CO2 or chemical activation with H3PO4 and KOH, the shape of the monolithic structure was preserved after the development of a microporous network (SBET up to 2400 m2/g). Both thermal and chemical activation had little effect on the macroporosity of the monoliths. Activation of these 3D carbons had to be performed with care to avoid heterogeneous skin/core activation and/or overactivation. Highly porous monoliths (SBET of 980 m2/g; open porosity of 70%) with outstanding compressive strength (10 MPa) could be obtained by thermal activation (CO2) of whey monoliths at 850 °C for 1.5 h. Additionally, the use of whey as a precursor provided the carbon monolith with a relatively high nitrogen content (ca. 3 wt.%).

The dry gasification process of solid fuels is a promising pathway to mitigate and utilize captured CO2 emissions toward syngas generation with tailored composition for several downstream energy conversion and chemical production processes. In the present work, comprehensive kinetic analysis and reaction modelling studies were carried out for olive kernel and lignite coal chars gasification reaction using pure CO2 as gasifying agent. Chars reactivity and kinetics of the gasification reactions were thoroughly examined by thermogravimetric analysis at three different heating rates and correlated with their physicochemical properties. The reactivity of olive kernel char, as determined by the mean gasification reactivity and the comprehensive gasification characteristic index, S, was almost three times higher compared to that of the lignite coal char. It was disclosed that the fixed carbon content and alkali index (AI) have a major impact on the reactivity of chars. The activation energy, Ea, estimated by three different model-free kinetic methods was ranged between 140 and 170 kJ/mol and 250–350 kJ/mol for the olive kernel and lignite coal chars, respectively. The activation energy values for the lignite coal char significantly varied with carbon conversion degree, whereas this was not the case for olive kernel char, where the activation energy remained essentially unmodified throughout the whole carbon conversion range. Finally, the combined Malek and Coats-Rendfrem method was applied to unravel the mechanism of chars-CO2 gasification reaction. It was found that the olive kernel char-CO2 gasification can be described with a 2D-diffusion mechanism function (D2) whereas the lignite coal char-CO2 gasification follows a second order chemical reaction mechanism function (F2).

Pomegranate peels, abundant raw precursor in Tunisia, were converted into activated carbon by means of microwave heating using phosphoric acid activation. The influence of the activation temperature and irradiation time on the process yield and porous texture of the resulting activated carbons was investigated. Textural properties were studied through the nitrogen adsorption-desorption isotherms and the scanning electron microscopy. The surface chemical properties were characterized by acid-base titration, point of zero charge, and Fourier-Transform Fourier transform infrared spectroscopy spectra. Paracetamol, a widely applied pharmaceutical, was selected to examine the adsorptive behavior of the activated carbon prepared in the optimum conditions. A series of experiments were conducted in a batch system to assess the influence of parameters, that is, pH, initial concentration, and adsorption temperature. The prepared activated carbons showed the high Brunauer-Emmett-Teller surface area (1,657 m2/g) and the important total pore volume (0.91 cm3/g) for an activation temperature and irradiation time of 450°C and 10 min, respectively. The adsorption performance illustrated an encouraging result. The Langmuir equilibrium adsorption capacity was 238 mg/g. Estimated thermodynamic parameters show a spontaneous and exothermic adsorption process. Microwave heating as a simple process provides a high-quality activated carbon in a short time. The obtaining results make microwave heating, combined with phosphoric acid, a feasible method for producing successful adsorbent for paracetamol removal.

In this work, unsupported Pd aerogel catalysts were synthesized for the very first time by using microwaves as a heating source followed by a lyophilization drying process and used towards formic acid electro-oxidation in a microfluidic fuel cell. Aerogels were also made by heating in a conventional oven to evaluate the microwave effect during the synthesis process of the unsupported Pd aerogels. The performance of the catalysts obtained by means of microwave heating favored the formic acid electro-oxidation with H2SO4 as the electrolyte. The aerogels' performance as anodic catalysts was carried out in a microfluidic fuel cell, giving power densities of up to 14 mW cm-2 when using mass loads of only 0.1 mg on a 0.019 cm2 electrode surface. The power densities of the aerogels obtained by microwave heating gave a performance superior to the resultant aerogel prepared using conventional heating and even better than a commercial Pd/C catalyst.

A novel design of a catalytic stirrer that can only be manufactured by 3D printing techniques is proposed. The stirrer blades are meshed and permeable to fluids. The STL files required for printing these novel stirrers with 2, 3, or 6 blades can be downloaded here. Two groups of STL files are provided depending on the material to be printed, namely PLA or any other selected filament for FDM printing; or whey pastes or any other selected paste for DIW printing. G-code and 3MF files are also provided to print, either by FDM or DIW, stirrers with meshed blades of different infills, namely solid (non-meshed or 100% infill), 50% infill, and 35% infill. The meshed patterns are provided by the PrusaSlicer® Laminator, as detailed in the corresponding publication.

We have designed a lab made extruder for direct ink writing (DIW) to be incorporated into a conventional fused deposition modelling (FDM) 3D printer. The STP and STL files required for printing the different parts of such extruder can be downloaded here. Instructions for their assembly and functioning are detailed in the paper.

This document outlines the design and 3D printing process of a double-stacked Archimedean spiral in PLA, intended to serve as a sacrificial template in the fabrication of a continuous flow reactor made of porous carbon.

This conversation discussed the topic of additive manufacturing of porous carbons and the potential use of 3D printing techniques such as robocasting, paste or ink printing, SLS, etc. to fabricate porous carbon parts. We also discussed the potential use of porous carbons as bone scaffolds and the current state of research in this field. It was also mentioned that AI language models like ChatGPT can assist in research and writing tasks, but they are not able to replace human researchers completely. The conversation also touched on the ethical implications of using information generated by AI models in scientific papers, and the importance of citing and attributing the information correctly. ________________ My conclusion is that ChatGPT is a good program to write texts in a very similar way to humans. However, in matters as specialized as this, the information it handles seems to be scarce and sometimes unfounded. In this case, almost all the references provided have been invented (!), so in this sense it is not reliable. Some of the claims that it made also do not appear to be substantiated., La conversación se centró en la fabricación aditiva de carbones porosos y su posible uso en andamios óseos. Se discutieron las diferentes técnicas de impresión 3D para fabricar piezas de carbono porosas y se mencionó el papel de las IA, como ChatGPT, en la investigación y redacción científica. Se destacó la importancia de considerar cuestiones éticas al utilizar información generada por una IA en artículos científicos. _________________ Mi conclusión es que ChatGPT es un buen programa para escribir textos de forma muy similar a los humanos. Sin embargo, en materias tan especializadas como esta, la información que maneja parece ser escasa y en ocasiones infundada. En este caso, casi todas las referencias aportadas han sido inventadas (!), por lo que en este sentido no es fiable. Algunas de las afirmaciones que hizo tampoco parecen estar fundamentadas.

UV-benzotriazoles have been identified as water micropollutants that cause serious problems for human health and the environment. Their low concentration in water bodies complicates their detection by direct water analysis, slowing the corrective actions to avoid bioaccumulation. In this regard, the use of graphene-based materials with a high affinity for non-polar molecules has been demonstrated to be a potential tool for the optimal separation and concentration of this type of molecules in solid phase extraction (SPE) processes. This work evaluates the potential of novel reduced graphene oxide aerogels (rGO) as extractants of mixtures of three UV-benzotriazoles in water at low concentrations. These rGO aerogels incorporate graphenic domains into a tough structure of polymeric chains by adding graphene oxide during the synthesis of resorcinol-formaldehyde gels. Aerogels with a different content and ordering of graphenic domains were obtained and characterized using Raman, XRD, SEM and nitrogen adsorption isotherms (−196 °C). The rGO aerogels that performed better as solid phase extractants were those containing 60% rGO. Aerogels with lower rGO contents (40%) required a high-temperature (2000 °C) treatment to render competitive results. The SPE methodology using selected rGO aerogels was optimized by varying the elution solvent, elution time and volume. The best performances, i.e., recoveries of 80–100% and enrichment factors of 12.5–50, were accomplished when using 0.8 mL of tetrahydrofuran (THF) as an elution solvent. As a result, a fast (10 min) and simple extraction method of UV-benzotriazoles in water was attained, achieving a detection limit of 1 ng mL−1. Selected aerogels were finally tested for the SPE of spiked samples of river waters, showing a similar performance to that observed with synthetic mixtures.

A new porous carbon structures made by sintering whey powder in a mold at 150ºC and subsequent carbonization and/or activation are described. These porous carbon structures represent a step beyond simple activated carbon monoliths, as they can take the shape of any mold and machined if necessary. These carbon materials have a porosity that can reach up 70%, made up of a system of hierarchical and interconnected pores, which gives them a high permeability. Furthermore, they have a much higher mechanical strength than other porous carbon monoliths.

[EN] The present invention relates to three-dimensional (3D) graphene aerogels which exhibit ultra-low density, large macroporosity and high electrical conductivity values and its process of obtainment. Said 3D graphene aerogels with controlled porosity and high electrical conductivity are extremely attractive for their application in several fields, especially as electrode materials for electrochemical devices such as supercapacitors, batteries, fuel cells and sensors. Therefore, the present invention also refers to an electrode for electrochemical energy devices comprising said 3D graphene aerogels., [FR] La présente invention se rapporte à des aérogels de graphène tridimensionnels (3D) qui présentent une ultra-faible densité, une grande macroporosité et des valeurs de conductivité électrique élevées et à leur procédé d'obtention. Lesdits aérogels de graphène 3D présentant une porosité contrôlée et une conductivité électrique élevée sont considérablement intéressants quant à leur application dans de nombreux domaines, en particulier en tant que matériaux d'électrode pour des dispositifs électrochimiques tels que des supercondensateurs, des batteries, des piles à combustible et des capteurs. Par conséquent, la présente invention fait également référence à une électrode destinée à des dispositifs à énergie électrochimique comprenant lesdits aérogels de graphène 3D.

We describe how robocasting and carbonisation of partially dehydrated whey, a surplus of the dairy industry, produced 3D porous carbons with custom morphologies. A relatively simple printing device was first used to manufacture 3D structures of whey pastes. The whey pastes behaved as a thermoset polymer when heated hence keeping the original shape of the printed pieces upon carbonisation, albeit an isotropic size reduction (23%) due to thermal shrinkage. The rheological properties of the whey pastes were similar to those of other inks commonly used in direct ink writing, with a shear thinning behaviour and static and dynamic yield stresses that predicted their printability in most robocasting devices. Once the 3D whey structures were printed, a heat-curing process was required to avoid the uncontrolled emission of volatiles that would otherwise distort them. When doing so, 3D lattices of carbon filaments with ca. 500 µm in diameter and ca. 425 µm mesh size were manufactured. The ash content of the carbonised structures, which is related to the salt content of the original whey, was reduced by conventional washing procedures, bringing about 3D hierarchical porous carbons (70% porosity) with modest specific surface areas (500 m2/g) and relatively high compressive strengths (5 MPa).

[Introduction] Somatostatin analogs (SSA) prolong progression-free survival (PFS) in patients with well-differentiated gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs). However, the eligibility criteria in randomized clinical trials (RCTs) have been restricted, which contrasts with the vast heterogeneity found in NENs., [Methods] We identified patients with well-differentiated (Ki-67% ≤20%), metastatic GEP-NENs treated in first line with SSA monotherapy from the Spanish R-GETNE registry. The therapeutic effect was evaluated using a Bayesian Cox model. The objective was to compare survival-based outcomes from real-world clinical practice versus RCTs., [Results] The dataset contained 535 patients with a median age of 62 years (range: 26–89). The median Ki-67% was 4 (range: 0–20). The most common primary tumor sites were as follows: midgut, 46%; pancreas, 34%; unknown primary, 10%; and colorectal, 10%. Half of the patients received octreotide LAR (n = 266) and half, lanreotide autogel (n = 269). The median PFS was 28.0 months (95% CI: 22.1–32.0) for octreotide versus 30.1 months (95% CI: 23.1–38.0) for lanreotide. The overall hazard ratio for lanreotide versus octreotide was 0.90 (95% credible interval: 0.71–1.12). The probability of effect sizes >30% with lanreotide versus octreotide was 2 and 6% for midgut and foregut NENs, respectively., [Conclusion] Our study evaluated the external validity of RCTs examining SSAs in the real world, as well as the main effect-modifying factors (progression status, symptoms, tumor site, specific metastases, and analytical data). Our results indicate that both octreotide LAR and lanreotide autogel had a similar effect on PFS. Consequently, both represent valid alternatives in patients with well-differentiated, metastatic GEP-NENs.

Whey, the main by-product of the dairy industry, is proposed as a sustainable binder for the production of extruded activated carbon. Coconut shell char was mixed with controlled quantities of either rehydrated whey powders or partially dehydrated liquid whey. After extrusion, extrudates were dried, and carbonised or activated under N2 or CO2 atmosphere, respectively. A comprehensive study of the effect of different parameters including binder proportion, coconut shell char particle size and carbonisation temperature was carried out. The composition of whey prompted Maillard reactions boosted with temperature that conferred a resin-like behaviour to the binder. Quality parameters of the resulting extrudates were their ball-mill hardness, real and bulk densities. All whey-bound pellets retained their original shape after the high temperature treatment. The hardness of those whey extrudates was particularly remarkable considering the biomass origin of this binder. The carbonisation temperature had little effect in the hardness or densities of the carbon pellets. The best pellet formulation comprised the use of coconut shell char powders with particle sizes < 212 µm, in mixtures having a 7/3 char/dry whey mass ratio. The properties of the pellets obtained after the activation of such pellets were comparable to those of commercial activated carbon extrudates. The use of partially dehydrated liquid whey rather than re-hydrated dry whey rendered very similar results. The alkalinity of the binder made the resulting activated carbons adequate for H2S removal at room temperature. An economic estimation of the process placed whey in a practical position within the binder market.

A series of xerogels with a properly designed porous structure and surface chemistry have been synthesized and evaluated as a host structure to promote the nucleation and growth of methane hydrates. Organic xerogels (OGs) have been synthesized from resorcinol-formaldehyde mixtures using a sol-gel approach and microwave heating. These xerogels are hydrophilic in nature and possess designed meso/macrocavities in the pore size range 5–55 nm. Carbon xerogels (CGs) have been synthesized from their organic counterparts after a carbonization treatment at high temperature. Interestingly, the carbonization process does not alter/modify substantially the porous network of the parent xerogels, while developing new micropores. Under water-supplying conditions, the two types of xerogels exhibit a large improvement in the methane adsorption capacity compared to the pure physisorption process taking place in dry conditions (up to 200% improvement), and associated with a significant hysteresis loop. These excellent values must be associated with the promoting effect of these xerogels in the water-to-hydrate conversion process. The comparison of OGs and CGs as a host structure anticipates that surface chemistry, total pore volume and pore size are critical parameters defining the extent and yield of the methane hydrate formation process.

Six carbon materials were obtained from the carbonisation of resorcinol/formaldehyde xerogels. All carbon xerogels (CXs) showed essentially the same microporosity but differed in their meso- or macroporosity, covering a wide interval of average meso- or macropore sizes from 10 nm to 3000 nm. The graphitisation of the CXs was heterogeneous, as detected by X-ray diffraction. The relative amount of the amorphous, turbostratic and graphitic carbon phases on the graphitised xerogels was different depending on the pore size of the CXs. Crystalline parameters such as interlayer spacings (d002) and crystallite sizes along the c-axis (Lc) were calculated from the different contributions and were also found to depend on the pore size of the parent CXs. Transmission electron microscopy and Raman spectroscopy analyses helped to identify nanostructures that could be assigned to the three carbon components of the graphitic xerogels. The occurrence of most of these nanostructures was compatible with a solid-phase transformation of the amorphous precursor. The electrical conductivity of the graphitised xerogels also depended on their original pore size, with values ranging from 2 S cm−1 for the materials with a 10 nm pore size to 18 S cm−1 for the materials with bigger pore sizes.

The current work explores the feasibility to improve the performance of a Direct Carbon Fuel Cell (DCFC): CO2 + bituminous coal|Co-CeO2/YSZ/Ag|Air by infusing a gasification catalyst (Co/CeO2) and/or Li-K carbonates mixture into the carbon fuel. The different fuel feedstock mixtures were characterized by various methods, involving chemical composition and proximate analysis, particle size distribution (PSD), X-ray diffraction (XRD), N2 adsorption-desorption (BET method), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM), to gain insight into the effect of catalyst and/or carbonates addition to fuel mixture physicochemical characteristics. An increase of the power output up to ca. 20 and 80% is achieved for carbon/catalyst and carbon/catalyst/carbonates mixtures, respectively, in comparison to bare carbon at 700 °C, demonstrating the pronounced effect of catalyst as well as its potential synergy with carbonates. It was also shown that the achieved maximum power density is directly associated with the CO formation rate, implying the importance of in situ formed CO on the electrochemical performance. The obtained findings are further discussed based also on the corresponding AC impedance spectroscopy studies, which revealed the beneficial effect of fuel feedstock additives (catalyst and/or carbonates) on ohmic and electrode polarization resistances. The present results clearly revealed the feasibility to improve the DCFC performance by concurrently infusing a gasification catalyst and carbonates mixture into fuel feedstock.

Electrodes for supercapacitors are commercially produced by mixing active material with a conductive additive and a binder. However, with some polymers such as carbon xerogels the conductive additives can be added during their synthesis in order to enhance interactions between the components of the electrode. In this work the performance in aqueous supercapacitors of a carbon xerogel and carbon black or graphene added during and post synthesis is compared. It was observed that, the more integrated the additive is within the carbon xerogel polymeric structure, the greater the differences in the final performance of the hybrid materials, being the sample with graphene oxide added during the synthesis of the organic gel the one with the best performance throughout the whole range of current densities studied.

The synthesis of resorcinol–formaldehyde (RF) xerogels is versatile enough to provide materials with custom pore size distributions in the meso-/macroporous range. Specifically, seven xerogels were synthesised by changing the pH of the same RF solution, from pH 3 to pH 6. The resulting materials presented meso-/macroporous size distributions with average pore sizes from < 5 to 510 nm, as determined by Hg intrusion and N2 adsorption. Most of the RF xerogels had very similar geometric densities, except for the gels obtained at the two highest pH values, which were more dense. Both flexural and uniaxial compression tests were carried out to determine the dependence of strength and stiffness on the porosity of the xerogels. The results followed a power-law relationship between the mechanical properties and the density of the materials. However, two series of RF xerogels were found to fit such law independently, with the gels obtained at the three most acidic pH values (pH 3–4) showing unexpectedly high compression moduli. Further characterisation of the xerogels microstructure revealed the existence of rod-like microstructures that would bear most loads during the compression tests. These microstructures would act as struts that, once broken, would cause the catastrophic failure (bursting) of the xerogel.

Algunas rutas, fotos y reseñas para conocer los lugares desde donde el conde asturiano Gonzalo Peláez llevó a cabo su rebelión contra el rey de León Alfonso VII en el siglo XII, y de cómo se relacionan con otros personajes históricos como: Urraca la Asturiana, primera y única reina de Asturias; Gausón, legendario caudillo astur; Gonzalo Peláez de Coalla, conde saqueador que asoló Grao; Alfonso Henriques, primer rey de Portugal o el gobernador Munuza, aniquilado con sus tropas, cuando abandonaba Asturias tras la derrota en Covadonga, en la legendaria batalla de Olalies.

The integration of 2D graphene sheets into a porous and macroscopic structure is extremely attractive for application in several electrochemical fields. In this regard, for the first time, the synthesis of 3D graphene aerogels is reported by using a rapid, easy, cost-effective, and scalable at industrial level methodology. These aerogels integrate the intrinsic properties of graphene with a high pore volume. To achieve this ultraporous graphene network, resorcinol/formaldehyde polymer with controllable porosity is employed as a binder and a cross-linker material, and a graphene oxide solution provides the graphene building blocks. Two series of materials with and without catalyst for resorcinol/formaldehyde reaction and with different synthesis conditions and graphene contents are studied. The resulting graphene aerogels present low density, large macroporosity, and electrical conductivity values as high as 852 S m−1, with 97.58% of porosity, which is the highest value of electrical conductivity reported so far in the literature for ultralight-weight graphene aerogels.

La presente invención se refiere a un monolito conformado de carbono obtenido a partir de polvo de lactosuero, a su procedimiento de obtención y a sus usos como andamio para su uso en ingeniería de tejidos celulares, como filtro de gases o líquidos, como tamiz molecular, como soporte de catalizador o como catalizador. La presente invención se engloba en el campo de los materiales de carbono y de la valorización de residuos industriales.

[EN] The present invention relates to a porous shaped carbon monolith obtained from lactoserum powder, to the method for obtaining it and to its uses as scaffolding in cell tissue engineering, as a gas or liquid filter, as a molecular sieve, as a catalyst medium or as a catalyst. The present invention falls within the field of the carbon materials and of industrial waste recovery, [ES] La presente invención se refiere a un monolito conformado de carbono obtenido a partir de polvo de lactosuero, a su procedimiento de obtención y a sus usos como andamio para su uso en ingeniería de tejidos celulares, como filtro de gases o líquidos, como tamiz molecular, como soporte de catalizador o como catalizador. La presente invención se engloba en el campo de los materiales de carbono y de la valorización de residuos industriales, [FR] La présente invention concerne un monolythe constitué de carbone obtenu à partir de poudre de lactosérum, son procédé d'obtention, et ses utilisations comme structure pour une utilisation en ingénieurie des tissus cellulaires, comme filtre de gaz ou de liquides, comme tamis moléculaire, comme support de catalyseur ou comme catalyseur. La présente invention concerne le domaine des matériaux de carbone et de la valorisation des résidus industriels

Porous carbon structures derived from whey powders are described and evaluated as potential scaffolds in bone tissue engineering. These materials have a porosity between 48% and 58%, with a hierarchical pore size distribution ranging from 1 to 400 micrometres. Compressive strength and elastic modulus are outstanding for such a porous material, being up to three times better than those of traditional HA or TCP scaffolds with similar porosities. They also present non-cytotoxic and bioactive behavior, due to their carbon-based composition that also includes some residual mineral salts content.

El objeto de la presente invención se refiere a un nuevo material de carbono consistente en un xerogel de carbono de elevada microporosidad y mesoporosidad y que está dopado con una cierta cantidad de grafeno homogéneamente distribuida en su estructura interna. Dicho material presenta una elevada área superficial específica y una elevada conductividad eléctrica, lo que le dota de unas excelentes propiedades electroquímicas para su uso como electrodo de supercondensadores. Este material se produce mezclando resorcinol, formaldehido, metanol, un catalizador y una suspensión acuosa de óxido de grafeno; sometiendo esta mezcla a un calentamiento con microondas y posteriormente a un proceso de carbonización o activación

[EN] The subject matter ofthe present invention relates toa novel carbon-based material consisting of a carbon xerogel with-high micro-and macroporosity and which is graphenated, doped with an amount of graphene homogeneously distributed throughout the intemal stmcture thereof. Said material exhibits a high specific surface area and high electrical conductivity, thereby conferring excellent electrochemical properties for use as a supercapacitor electro de. Said material is produced by mixing resorcinol, formaldehyde, methanol, a catalyst andan aqueous suspension of graphene oxide, subjecting said mixture to microwave heating and subsequently a carbonisation or activation process. The present invention also relates to the use ofthe nanoporous graphenated carbon-based material as an electrode in supercapacitors, [ES] El objeto de la presente invención se refiere a un nuevo material de carbono consistente en un xerogel de carbono de elevada microporosidad y mesoporosidad y que está grafenado, dopado con una cierta cantidad de grafeno homogéneamente distribuida en su estructura interna. Dicho material presenta una elevada área superficial específica y una elevada conductividad eléctrica, lo que le dota de unas excelentes propiedades electroquímicas para su uso como electrodo de súpercondensadores. Este material se produce mezclando resorcinol, formaldehido, metanol, un catalizador y una suspensión acuosa de óxido de grafeno; sometiendo esta mezcla a un calentamiento con microondas y posteriormente a un proceso de carbonización o activación. Además, la presente invención se refiere al uso del material de carbono nanoporoso grafenado como electrodo de súpercondensadores.

Carbón nanoporoso grafenado, procedimiento de preparación y uso como electrodo. El objeto de la presente invención se refiere a un nuevo material de carbono consistente en un xerogel de carbono de elevada microporosidad y mesoporosidad y que está dopado con una cierta cantidad de grafeno homogéneamente distribuida en su estructura interna. Dicho material presenta una elevada área superficial específica y una elevada conductividad eléctrica, lo que le dota de unas excelentes propiedades electroquímicas para su uso como electrodo de supercondensadores. Este material se produce mezclando resorcinol, formaldehido, metanol, un catalizador y una suspensión acuosa de óxido de grafeno; sometiendo esta mezcla a un calentamiento con microondas y posteriormente a un proceso de carbonización o activación.

Three different hybrid carbon xerogels containing Graphene Oxide (AXGO), Micronized Graphite (AXMG) and Carbon Black (AXCB) were synthesized using an easy, fast and affordable method. These three additives were initially selected to improve the electrical conductivity of the pristine activated carbon xerogel (AX) thus expecting to improve its performance in aqueous supercapacitors. Capacitances of the corresponding devices were measured as a function of current density and results of the high and low charge transfer regime of the supercapacitors were discussed separately. In both regimes, the differences observed between the hybrid electrodes were analyzed on the basis of the concurrent influence of the micro and mesoporosity, surface chemistry and electrical conductivity of the materials. Accordingly, even though all the hybrid carbon xerogels showed higher electrical conductivities, only AXGO rendered a better performance than AX, showing the highest capacitances in the whole interval of intensities studied. Consequently, at 16 A g−1, the energy and power densities of the AXGO supercapacitors increased up to 16% and 97%, respectively, with respect to AX, and of 143% and 409%, respectively, with respect to a commercial activated carbon used as reference. The performance of AXCB and, especially AXMG was worse than AX supercapacitors due to a combination of inadequate pore size distributions and/or a poor surface chemistry. Finally, TEM analysis helped to understand the different way the three additives were affecting the nanostructure (and final properties) of the hybrid carbon xerogels.

Extensive studies on the correlation between synthesis variables and the final properties of resorcinol-formaldehyde carbon gels have been performed. This knowledge allows us to obtain carbon gels with analogous mean pore sizes and porosity from different combinations of synthesis variables. However, although the materials exhibit these similar characteristics, their behaviors may be very different in certain applications. Since the distribution and connectivity of the polymeric clusters are strongly affected by variables such as the amount of water and methanol in the precursor solution, it seems that the pore tortuosity and thus the permeability of the materials are also dependent on these factors. Further analysis of a series of carbon gels with the apparent same porosity shows how an increase in the amount of water or a suitable combination of methanol content and the pH of the precursor solution used for the polymerization process generate less tortuous pore structures. This allows us to attain even finer tuning of the porous structure of RF carbon gels either to reduce pressure drop or to increase the residence time of solutes in separation processes.

This study focuses on the use of a microwave reactor that combines biomass pyrolysis, at mild temperature, with catalytic reforming of the pyrolytic gas, using activated carbon, for generating hydrogen-rich synthesis gas. The traditional pyrolysis of biomass coupled with the reforming of its pyrolytic yields were also conducted using an electrically heated reactor. The bio-oil attained from conventional pyrolysis was higher in comparison to the yield from microwave pyrolysis. The reforming of the pyrolytic gas fraction led to reductions in bio-oil yield to <3.0 wt%, with a simultaneous increase in gaseous yields. An increase in the syngas and H2 selectivity was discovered with the reforming process such that the use of microwave pyrolysis with activated carbon reforming produced 85 vol% synthesis gas fraction containing 55 vol% H2 in comparison to the 74 vol% syngas fraction with 30 vol% H2 obtained without the reforming. Cracking reactions were improved with microwave heating, while deoxidation and dehydrogenation reactions were enhanced by activated carbon, which creates a reduction environment. Consequently, these reactions generated H2-rich syngas formation. The approach implemented in this study revealed higher H2, syngas yield and that the overall LHV of products has huge potential in the transformation of biomass into high-value synthesis gas.