Nowadays, biofuels represent a large part of renewable energies destined to substitute fossil fuels, and to reduce the negative impact on the environment. Bioethanol is obtained by alcoholic fermentation, and is used pure or mixed with other petroleum derivatives as fuel. Use, manipulation, storage and transport of these substances, at any scale, demand the implementation of materials, such as aluminum, that has excellent mechanical properties, as well as low density. Generally, these characteristics are improved by alloying aluminum with silicon (in order to decrease the thermal expansion coefficient and increase wear resistance) and magnesium (to increase hardness of the material). Potentiodynamic polarization and electrochemical spectroscopy impedance techniques were used on this research, in order to determine the corrosion resistance of Al-10 wt.%Si, Al-12 wt.%Si, Al-2%Mg and Al-4 wt.%Mg alloys in an alcoholic electrolyte (bioethanol of Misiones province, Argentina industry). Comparing to pure aluminum, aluminum-silicon alloys presented better corrosion resistance. On the other hand, aluminum-magnesium alloys didn’t have such improvement. By using optical metallographic microscope, no differences were found on the surfaces of alloys after being exposed to the alcoholic electrolyte.

The actual demand of energy and the environmental concerns together with the reduced fossil fuel reserves have played an important role to convert the second generation bioethanol production into an attractive research area. To convert lignocellulosic biomass to bioethanol the cellulosic components must be hydrolyzed to fermentable sugars. Trichoderma fungi secrete large amounts of enzymes of industrial interest such as cellulases, able to degrade holocellulose in the saccharification of lignocellulosic biomass. In this work we evaluated endo-1.4-β-glucanases enzymatic secretion of Trichoderma koningiopsis from Misiones province, in synthetic medium, with carboxymethylcellulose as carbon source; and semi-synthetic medium, with pine sawdust as carbon source. Higher values of endo-1.4-β-glucanases were reached when the semi-synthetic medium was used. It could be concluded that pine sawdust seems to be a good candidate for utilization as carbon source in culture media aiming to obtain good enzyme secretion, being also an economic and easily available substrate

The contamination of water bodies with toxic compounds from the agricultural, industrial, and domestic sectors is a serious environmental problem. Adsorption is one of the simplest, most functional, and economical methods for treating large volumes of water and removing its contaminant load. Thanks to its nanoporous structure, versatility, chemical inertness, and low-cost synthesis, anodic aluminum oxide (AAO) can be used as an adsorbent in a wide range of applications. In this work, nanostructured AAO coatings were successfully synthesized, and their performance as adsorbents was evaluated in decolorization tests of Eriochrome Black T (EBT) solutions. The adsorption process was found to be dependent on the initial dye concentration, agitation, temperature, and contact time. At 25 °C and 16 mg·L⁻¹ initial EBT concentration, a maximum removal efficiency (%R) of 78% was obtained after 4.5 h at 500 rpm and after 5.5 h at 100 rpm, while without agitation, after 8.3 h of treatment, the highest %R was 40%. Furthermore, the adsorption rate increased significantly with temperature, reaching a %R of 99% after 2.25 h at 60 °C and 500 rpm. Additionally, it was demonstrated that the adsorbent can be used up to four times with a removal efficiency greater than 50%.

OBTENCIÓN DE AZÚCARES FERMENTABLES A PARTIR DE ASERRÍN DE PINO PRETRATADO SECUENCIALMENTE CON ÁCIDO-BASE