Desarrollo, Producción e Innovación en la Investigación científica

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    Valorization of glycerol from the biodiesel industries as a renewable substrate for producing DHA using microporous zeolites modified with noble metals.
    (2017) Diguilio, Eliana; Galarza, Emilce Daniela; Renzini, María Soledad; Pierella, Liliana Beatriz
    Glycerol (Gly) is an important renewable resource derived from biodiesel industries and it is used in food, cosmetic and pharmaceutical applications. Due to increasing production of biodiesel the price of the main by-product has decline, due to this last years has had special attention. Gly is a platform molecule to obtain different high value fine chemicals like aldehydes, ketones and organic acids, including dihydroxyacetone (DHA), glyceric acid, glycolic acid and lactic acid. By liquid phase oxidation of Gly under mild conditions, using microporous zeolites modified with the incorporation of noble metals such as Pt and Au, it was possible to obtain an interesting production of DHA.
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    Influence of the solid catalyst porosity on the products yields and composition from peanut shells pyrolysis
    (2017) Fermanelli, Carla S.; Diguilio, Eliana; Saux, Clara; Pierella, Liliana Beatriz
    Argentine is the first worldwide peanut (Arachis hypogaea) exporter, with around 600,000 tons per year of commercialization. Nevertheless, peanut production leaves around a 25 vol% of shells as residue of the process. This low density waste (0.10 kg/dm3) is actually burned or buried, causing serious environmental problems, or stored in silos but with an auto ignition risk characteristic of this kind of material. As an alternative in order to solve this issue and to obtain interesting chemical products, a catalytic pyrolysis process is proposed. In this sense, two type of porous solid materials were studied as catalysts for the reaction: a traditional microporous ZSM-11 zeolite (H-ZSM-11 micro) and a hierarchical form of the same class of MEL zeolite (H-ZSM-11 micro/meso). From the pyrolysis reaction three products lines are obtained: a liquid fraction, called bio-oil; a solid one, known as bio-char, and gases. The bio-oil is a high energy density liquid fuel, which could be used as substitute of fuel-oil [1]. However, high oxygen compounds concentration is obtained from the thermal process that makes this product of reduced stability and poor heating value. We propose the use of the above mentioned zeolites as catalysts for the in situ cracking reactions for the deoxygenation of the components and to obtain high value chemical products.
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    Effect of zeolite matrix over products distribution of catalytic pyrolysis of biomass waste
    (2018) Fermanelli, Carla S.; Diguilio, Eliana; Saux, Clara; Pierella, Liliana Beatriz
    Thermo-chemical conversion of biomass has become a promising technology for fuel and platform molecules production. In Argentina, peanut (Arachis hipogaea) industry leaves about 200,000 tons of biomass waste per year, all concentrated in the central area of the country causing serious environmental issues. In this sense, pyrolysis (thermochemical process in absence of oxygen) is an adequate technique to process rich in lignin materials. Three types of zeolites, namely ZSM-11, Beta and Y have been tested as heterogeneous catalysts in biomass pyrolysis in order to evaluate the effect of the zeolite type over bio-oil yield and products selectivity. While ZSM-11 and Beta zeolites were obtained by the traditional hydrothermal crystallization method1,2 Y zeolite was commercially acquired from Sigma Aldrich. The formers, after synthesized were finally exchanged with NH4Cl solution, desorbed in N2 flow and further calcined at 500 °C to obtain the protonic forms. The catalysts were named H-ZSM-11, H-Beta and H-Y. Fresh and used materials were widely characterized by XRD, FTIR, ICP and BET techniques. Peanut shells provided by “Lorenzati, Ruetsch y Cia” (Ticino, Córdoba, Argentina) were washed, grinded and sieved to obtain particle size less than 3.35 mm (ASTM E-11/95) prior to be evaluated. Grinding diminishes heat transfer problems associated with solids3. Pyrolysis reactions were done in a quartz fixed bed reactor (23 mm I.D., 290 mm length) at 500 °C under 60 mL/min of N2 flow for 10 min. Biomass was located in a porous base glass basket inside the reactor and over the catalyst bed. Condensable products were collected in a liquid trap submerged in a refrigerant bath (-15°C) and further analyzed and quantified by GC and GC/MS. Both catalytic and non-catalytic runs were performed for comparison purpose. Three different products are obtained from the pyrolysis process, called: bio-oil, bio-gas and bio-char. In terms of products yields, while bio-char yield was similar in the three cases studied, bio-oil yield varied in the range of 30-50%. The maximum throughput was achieved with H-ZSM-11 zeolite and the minimum was observed when H-Y catalyst was the one utilized. Bio-gas yield was comparable in the cases of H-ZSM-11 and H-Beta (around 20%), but it was much higher with H-Y zeolite. This result indicates that H-Y matrix produces higher cracking of the organic molecules after pyrolysis. Higher concentration of desired products namely, toluene, furfural, xylene, 5-hydroxymethyl furfural (5-HMF), and trimethyl benzene (TMB), among others was observed when H-ZSM-11 catalyst was employed. Moreover, selectivity towards xylene and 5-HMF was 10% and 5% respectively, compared to the 1.5% reached when H-Beta zeolite was used and 0% with H-Y. The use of zeolites in biomass pyrolysis is beneficial for interesting chemical production, particularly H-ZSM-11 zeolite. This catalyst has proven to generate not only higher bio-oil yields than the others studied, but also a liquid with higher concentration of desired products.