The use of tomato plant residues (i.e., stems, leaves, etc.) as a substrate for catalytic pyrolysis of biomass was investigated. A comprehensive study was conducted to investigate the impact of catalysts on the performance of different pyrolysis fractions (i.e., gas, biosolid, waxes, and bioliquid) as well as the distribution of products within the bioliquid. The catalysts employed in this study were derived from two distinct types of zirconia. The first type was synthesized by a conventional sol-gel method, while the second type was prepared with a modified method aimed at improving the presence of mesopores. This modification involved the incorporation of Pluronic 123. These materials were designated ZrO₂ and ZrO₂P25, respectively. Both types of zirconia were used as supports for tungstophosphoric acid (H₃PW₁₂O₄₀, TPA), a heteropolyacid with a Keggin structure, in the preparation of catalysts with strong acid sites. The results demonstrated that the bioliquid yield of the non-catalytic fast pyrolysis of tomato plant waste was approximately 23% and that the obtained bioliquid contained a wide variety of molecules, which were detected and quantified by GC-MS. In the presence of the catalysts, both the bioliquid yield and the distribution of bioliquid products were substantially modified. Furthermore, the possible sugar degradation pathways leading to the formation of the molecules present in the pyrolytic bioliquids were thoroughly examined. The results obtained from this study indicate that the physicochemical characteristics of the catalysts, specifically their pore size and acidity, have a significant impact on the selectivity of the catalytic processes towards valuable molecules, including anhydro-sugars and furanic derivatives such as furfural and furfuryl alcohol.

Background: Aminoisoquinolines are an important class of heterocyclic compounds. These compounds present a wide range of pharmacological properties including antimalaric, anticonvulsant and anti-inflammatory. Although several preparation routes may be found in the literature for the preparation of these compounds, many of these methods present difficulties, including laborious isolation methods, drastic conditions and extended reaction times. Methods: The synthesis of N-substituted 1-alkyl and 1-aryl- 3-aminoisoquinolines is developed through the reaction of 2-acylphenylacetonitriles with amines under microwave irradiation conditions. The reactions were performed in ethanol as a solvent without the use of catalyst. In parallel, these reactions were performed under identical conditions of temperature using P2O5/SiO2 as a catalyst in different amounts. Results: A series of N-substituted 1-alkyl and 1-aryl- 3-aminoisoquinolines were synthesized using microwave irradiation with as high selectivity, short reaction times and without the use of catalyst. The use of P2O5/SiO2 as catalyst under microwave irradiation conditions was not effective for these reactions. Conclusion: The results show an efficient method for the synthesis of N-substituted 1-alkyl and 1-aryl- 3-aminoisoquinolines by the reaction of 2-acylphenylacetonitriles with amines using microwave irradiation. Some important advantages for this method include a strong decrease in reaction time, a good selectivity, and the absence of catalyst, with simplicity in operation and a benefit to the environment.

Se llevó a cabo la pirólisis, tanto catalítica como no catalítica, de un sustrato biomásico compuesto por hojas y tallos de remolacha hortícola (Beta vulgaris subsp. vulgaris), con el propósito de evaluar la influencia de pretratamientos ácidos y del empleo de catalizadores en el rendimiento y la composición de los biolíquidos obtenidos. Los resultados mostraron que el pretratamiento con ácido fosfórico (H₃PO₄) favoreció la obtención de un biolíquido enriquecido en alcoholes de cadena corta, principalmente etanol y metanol. Asimismo, al promover rutas de deshidratación, se facilitó la formación de compuestos oxigenados de interés, como el furfural. Por otra parte, la utilización de la zeolita ácida H-ZSM5 en la catálisis secundaria condujo a un incremento en la proporción de compuestos de bajo peso molecular, destacándose el ácido acético (36.9%) y el metanol (14%). Este comportamiento se asocia con la intensificación de reacciones de ruptura de enlaces. En conjunto, los tratamientos aplicados demostraron ser estrategias eficaces para orientar la pirólisis hacia productos de mayor valor agregado, optimizando tanto el rendimiento como el perfil químico del biolíquido derivado de residuos lignocelulósicos de remolacha.

This work presents the synthesis, characterization, and application of zirconium oxide (ZrO₂)-based catalysts, modified with macro (silica nanospheres, NSP-SiO₂) and mesopore templates (Pluronic 123), impregnated with tungstophosphoric acid (TPA), in the catalytic pyrolysis of tomato agro-industrial residues. The NSP-SiO₂ (SXX) and P123 (PYY) amount mainly influences the ZrO₂SXXPYY-specific surface area (S_BET) and average pore diameter (D_p). ³¹P MAS NMR and FT-IR characterization results show that TPA (H₃PW₁₂O₄₀) was partially transformed into [P₂W₂₁O₇₁]⁶⁻ and [PW₁₁O₃₉]⁷⁻ during the synthesis steps. The acidic properties of ZrO₂SXXPYY samples containing 25 and 50 wt% of TPA (ZrO₂SXXPYYT25 and ZrO₂SXXPYYT50, respectively) are dependent on both the TPA content and the support nature. Bio-oil composition and product selectivity were strongly influenced by the textural and acid-based properties of the catalysts. Notably, non-catalytic pyrolysis favored pathways leading to C2 compounds, with a high content of acetic acid and hydroxyacetone. In contrast, the use of catalysts promoted the formation of higher molecular weight oxygenated compounds (C5–C6), specifically furans, aldehydes, and ketones.

This work presents the results of the acetalization reaction between furfural and polyols (ethylene glycol or glycerol), employing an ionic liquid, 1-(4-sulfonic acid) butyl-3-methylimidazolium hydrogen sulfate, [C4SO3Hmim][HSO4], as a catalyst. Two series of catalysts were prepared and characterized. These catalysts were supported on silica gel 60 and on SBA-15 mesoporous silica, with variable IL loading (10 - 50 wt%). All of them showed good activity in the formation of the desired cyclic ethers, 2-(furan-2-yl)-1,3-dioxolane and the cis-trans (2-(furan-2-yl)-1,3-dioxolan-4-yl) methanol and cis-trans (2-(furan-2-yl)-1,3-dioxan-5-ol isomers. Furthermore, the activity exhibited by some of these catalysts surpassed that of the unsupported IL. The catalyst SBAIL30 was the most active, with a cyclic acetal yield of 51%. This particular sample is characterized by its elevated number of strong acid sites, a property that is supported by the results of the XPS analysis. These strong acid sites are believed to be derived from the presence of sulfonic groups within the IL. The use of heterogeneous catalysts had a significantly impact on the stereochemistry of the reaction. While the 6-membered ring is the most thermodynamically stable product, SILx and SBAILx catalysts were found to favor the formation of the 5-membered ring in a higher proportion than that found in the reaction performed in the absence of catalyst.