Use of pineapple waste as fuel in microbial fuel cell for the generation of bioelectricity

The excessive use of fossil sources for the generation of electrical energy and the increase in different organic wastes have caused great damage to the environment; these problems have promoted new ways of generating electricity in an eco-friendly manner using organic waste. In this sense, this research uses single-chamber microbial fuel cells with zinc and copper as electrodes and pineapple waste as fuel (substrate). Current and voltage peaks of 4.95667 ± 0.54775 mA and 0.99 ± 0.03 V were generated on days 16 and 20, respectively, with the substrate operating at an acid pH of 5.21 ± 0.18 and an electrical conductivity of 145.16 ± 9.86 mS/cm at two degrees Brix. Thus, it was also found that the internal resistance of the cells was 865.845 ± 4.726 Ω, and a maximum power density of 513.99 ± 6.54 mW/m2 was generated at a current density of 6.123 A/m2 , and the final FTIR spectrum showed a clear decrease in the initial transmittance peaks. Finally, from the biofilm formed on the anodic electrode, it was possible to molecularly identify the yeast Wickerhamomyces anomalus with 99.82% accuracy. In this way, this research provides a method that companies exporting and importing this fruit may use to generate electrical energy from its waste.Campus Trujill

Use of tangerine waste as fuel for the generation of electric current

Fruit waste has increased exponentially worldwide, within which tangerine is one of those that generates a greater amount of organic waste, which is currently not fully used. On the other hand, microbial fuel cells (MFCs) are presented as an opportunity to take advantage of organic waste to generate electricity, which is why the main objective of this research is to generate bioelectricity using tangerine waste as a substrate in microbial fuel cells using zinc and copper electrodes. It was possible to generate current and voltage peaks of 1.43973 ± 0.05568 mA and 1.191 ± 0.035 V on days eighteen and seventeen, respectively, operating with an optimum pH of 4.78 ± 0.46 and with electrical conductivity of the substrate of 140.07 ± 3.51 mS/cm, while the Brix degrees gradually decreased until the last day. The internal resistance determined was 65.378 ± 1.967 Ω, while the maximum power density was 475.32 ± 24.56 mW/cm2 at a current density of 5.539 A/cm2 with a peak voltage of 1024.12 ± 25.16 mV. The bacterium (Serratia fonticola) and yeasts (Rhodotorula mucilaginosa) were identified in the substrate with an identity of 99.57 and 99.50%, respectively. Finally, the cells were connected in series, managing to generate 3.15 V, which allowed the turning on of a red LED light.Campus Trujill

Material para cátodo con alta energía para baterías recargables en ion-litio

Se sintetizó un material compuesto de partículas de azufre y carbón, el cual fue caracterizado estructuralmente mediante las técnicas de difracción de rayos X y microscopía electrónica de barrido. Los resultados mostraron una estructura cristalina trigonal y una dispersión de las partículas de azufre en una superficie de carbón, con tamaños que están entre 2-5μm. El material resultante se estudió como cátodo de baterías recargables de ion-litio. Se fabricaron baterías del tipo celdas de moneda con la finalidad de estudiar el comportamiento electroquímico, colocando como cátodo el material sintetizado. 1M de LiCF3SO3 disuelto en 1,3- Dioxano (DOL) y Dimetoxietano (DME), a razón de 1:1, se usó como electrolito y litio como ánodo. Las baterías fueron caracterizadas electrónicamente mediante las técnicas de carga y descarga. Los resultados mostraron una alta capacidad especifica de 900 mAh/g y sin atenuación hasta 80 ciclos.Particles consisting of sulfur and carbon were synthesized and structurally characterized by means of X-Ray Diffraction and a scanning electron microscope. The results show a trigonal crystal structure with the sulfur particles dispersed on a carbon surface, with a variety of sizes ranging between 2-5 μm. The resulting material was tested as a cathode in Lithium-ion batteries. Coin cell batteries were fabricated to study the electrochemical behavior using the synthesized material as a cathode. 1M of LiCF3SO3 dissolved in 1,3-Dioxane (DOL) and Dimethoxymethane (DME), on a 1:1 ratio, was used for the electrolyte and Lithium was used as an anode. The batteries were electronically characterized by discharging and re-charging techniques, the results showed a high specific capacity of 900 mAh/g without an attenuation for up to 80 cycles.Tesi

Reinforcement of mango seed starch based biodegradable films through incorporation of mango peel extracts for active packaging [Reforzamiento de películas biodegradables de almidón de semilla de mango mediante la incorporación de extracto de piel de mango para su uso como envase activo]

RESUMEN Este trabajo tuvo como finalidad estudiar el efecto de la incorporación de extracto de piel de mango (EPM) sobre las propiedades de películas biodegradables fabricadas a partir de almidón de semillas de mango y comprobar su potencial para ser usado en envasado activo. El EPM fue añadido en el proceso de gelatinización en concentraciones de 5, 10 y 15% wt. Las propiedades de las películas fabricadas fueron caracterizadas usando Microscopía Electrónica de Barrido (MEB), Espectroscopía FTIR, cinética de absorción de agua y curvas Esfuerzo-Deformación. Las micrografías MEB muestran una formación más limpia de residuos, sin vacíos ni grietas en las películas con EPM. Los análisis FTIR confirman la formación de bioplástico de almidón por la presencia de los grupos funcionales O-H, C-H, C-O y O=H. Por otro lado, se confirma que al añadir EPM se logra un aumento en la rigidez de las películas, pero una disminución en la elasticidad, además de reducir la capacidad de absorber agua. Este trabajo evidencia los beneficios de los residuos de mango y su potencial para su uso en la industria alimentaria como material para envase activo.ABSTRACT The aim of this work was to study the effect of the incorporation of mango peel extract (MPE) on the properties of biodegradable films made from starch obtained from mango seeds and to verify its potential to be used in active packaging. The MPE was added in the gelatinization process in concentrations of 5, 10 and 15% wt. The properties of the manufactured films were characterized using SEM, FTIR, water absorption kinetic and Stress-Strain curves. SEM micrographs show a formation free of residues, without gaps or cracks in MPE films. FTIR analysis confirm the formation of bioplastic starch by the presence of the functional groups O-H, C-H, C-O and O=H. On the other hand, it is confirmed that adding MPE achieves an increase in stiffness of the films but a decrease in elasticity, in addition reducing the capacity of water absorption. This work demonstrates the benefits of mango residues and their potential for use in the food industry as an active packaging material