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This work compares the effect of using a solar reactor against a conventional electrical furnace to obtain carbon materials by pyrolysis of a lignocellulosic precursor. The solar reactor is directly irradiated and includes modifications to improve the control of the process and the reproducibility of solar experiments. A bagasse of agave creole was selected as the lignocellulosic precursor or biomass to obtain carbon materials at temperatures of 700 °C. Comparing carbons produced by conventional and solar pyrolysis, higher crystallinity and lower hydrophilicity are evident in the former. Moreover, conventional pyrolysis tends to promote a more homogeneous porous structure in comparison to solar pyrolysis. However, within the spectrum of solar carbons produced, the morphology of biomass plays a crucial role in influencing the chemical composition and porosity properties. Specifically, the use of fibers instead of powders to produce carbons through solar pyrolysis results in a more homogeneous porosity, attributed to an enhanced volumetric absorption of solar radiation. This modification leads to a significant improvement in capacitance, increasing from 125 F/g to 175 F/g at 5 mV/s in aqueous electrolytes. The carbons from the solar furnace are reproducible, underlying the potential of the proposed process towards a sustainable alternative. To achieve a theoretical reference, the pyrolysis process was mimic trough Reactive Molecular Dynamics calculations modeling the initial structural conditions of agave biomass with its corresponding lignocellulosic components and considering analogous thermal conditions. The resulting carbon structures at the end of the simulations showed structural properties that are consistent with those observed in the pair distribution functions obtained from XRD and the pore size distribution from physisorption analyses. This combined experimental–theoretical approach offers the potential to elucidate porous carbon structures derived from pyr

A full description of computational details related to molecular dynamics, radial distribution function computation, and Envelope Density assessment, along with experimental results concerning SEM images of group I and group II carbon materials.-- S0.1. Computational Details: S0.1.1. Simulations with Molecular Dynamics. S0.1.2. Radial distribution function computation. S0.1.3. Envelope Density assessment. S0.2. Complementary experimental results

[EN] The coupling of concentrated solar technologies and thermochemical biomass conversion is a promising alternative because there is an improvement on the process efficiency and a reduction of the environmental impact related to the use of fossil fuels for heat process. Therefore, the use of solar pyrolysis of agro-industrial wastes into fuels results attractive due to the biomass versatility to be transformed in a variety of products. In the present work, leaves of agave Angustifolia were used as raw material to performed the solar pyrolysis in the IER-UNAM solar furnace (Mexico) to produce amorphous carbon. The experiments were performed in a borosilicate reactor at different temperatures (450-1550 °C), with an average heating rate of 30 °C/min and 60 min of residence time. The main results show a variety of yields in the char produced from 28-14%, and conversion up to 85%. In addition, according to the temperature range, the amorphous chars produced may be suitable for energy storage in symmetric supercapacitors as carbon electrodes., [ES] El acoplamiento de tecnologías de concentración solar y los procesos termoquímicos de conversión de biomasa son una alternativa prometedora, debido al mejoramiento de la eficiencia del proceso y reducción del impacto medioambiental asociado al uso de combustibles fósiles para la generación de calor de proceso. Por ello, el uso de pirólisis solar de desechos agroindustriales hacia combustibles resulta atractiva debido a la versatilidad de la biomasa para ser convertida en una variedad de productos. En el presente trabajo, hojas de agave Angustifolia fueron usadas como materia prima para llevar a cabo la pirólisis solar en el horno solar del IER-UNAM (México) para la producción de carbón amorfo. Los experimentos se realizaron a diferentes temperaturas (450-1550 °C), con una rampa de calentamiento promedio de 30 °C/min y 60 min de tiempo de residencia. Los resultados principales muestran una variedad en los rendimientos de 28-14 % y una conversión de hasta 85%. Adicionalmente, de acuerdo al rango de temperatura analizado, la producción de carbones amorfos puede ser adecuada para su uso como electrodos en supercapacitores simétricos, para el almacenamiento de energía.