Menú secundario

Artículos SCI



2023


Materiales de Diseño para la Energía y Medioambiente

Plasticized, greaseproof chitin bioplastics with high transparency and biodegradability

Heredia-Guerrero, JA; Benitez, JJ; Porras-Vazquez, JM; Tedeschi, G; Morales, Y; Fernandez-Ortuno, D; Athanassiou, A; Guzman-Puyol, S
Food Hydrocolloids, 145 (2023) 109072

Show abstract ▽

A mixture of trifluoroacetic acid:trifluoroacetic anhydride (TFA:TFAA) was used to dissolve chitin from shrimp shells. Free-standing films were prepared by blending the chitin solution and glycerol at different percentages, followed by drop-casting, and the complete evaporation of the solvents. After this process, the chitin matrix showed an amorphous molecular structure, as determined by X-ray diffraction. Optical, mechanical, thermal, and antioxidant properties were also thoroughly investigated. The incorporation of glycerol induced a plasticizing effect on the mechanical response of films and improved their transparency. In addition, hydrodynamic and barrier properties were determined by contact angle and water vapor/oxygen transmission rates, respectively, and revealed typical values of other polysaccharides. These bioplastics also presented an excellent greaseproof behavior with the highest degree of oil repellency as determined by the Kit test. Moreover, the overall migration was evaluated by using Tenax & REG; as a dry food simulant and levels were compliant with European regulations. Their antifungal properties were tested using Botrytis cinerea as a model. Biodegradability was also determined by measuring the biological oxygen demand in seawater. Degradation rates were high and similar to those of other fully-degradable materials.


Diciembre, 2023 | DOI: 10.1016/j.foodhyd.2023.109072

Materiales de Diseño para la Energía y Medioambiente

Incorporation of bioactive compounds from avocado by-products to ethyl cellulose-reinforced paper for food packaging applications

Acquavia, MA; Benitez, JEJ; Bianco, G; Crescenzi, MA; Hierrezuelo, J; Grife-Ruiz, M; Romero, D; Guzman-Puyol, S; Heredia-Guerrero, JA
Food Chemistry, 429 (2023) 136906

Show abstract ▽

Reinforced films were fabricated by impregnating paper in ethyl cellulose solutions. After solvent evaporation, the infused ethyl cellulose acted as binder of the paper microfibres and occupied the pores and cavities, thus improving the mechanical and barrier properties. To prepare active films, avocado by-products from guacamole industrial production were extracted in ethyl acetate. Then, the extract (optimized to be rich in phenolic compounds and flavonoids and mainly composed by lipids) was incorporated to the paper reinforced with the highest content of ethyl cellulose. In general, the addition of the avocado by-products extract decreased the water uptake and permeability, improved the wettability, and increased the biodegradability in seawater and the antioxidant capacity. In addition, these films acted as barriers and retainers for Escherichia coli and Bacillus cereus. The potentiality of these materials for food packaging was demonstrated by low overall migrations and a similar food preservation to common low-density polyethylene.


Diciembre, 2023 | DOI: 10.1016/j.foodchem.2023.136906

Fotocatálisis Heterogénea: Aplicaciones

Bismuth ferrite as innovative and efficient photocatalyst for the oxidation of As(III) to As(V) under visible light

Chianese, L; Murcia, JJ; Hidalgo, MC; Vaiano, V; Iervolino, G
Materials Science in Semiconductor Processing, 167 (2023) 107801

Show abstract ▽

The presence of As in drinking water is a problem felt all over the world. In particular, arsenic is present in +3 (As(III)) and +5 (As(V)) oxidation states. However, As(III) is the most toxic and difficult to remove with conventional adsorption processes. A pre-oxidation process is therefore necessary. In this work, we report, for the first time, the use of BiFeO3 as a visible-light active photocatalyst for the complete and fast oxidation of As(III) to As(V) in water. In particular, the influence of annealing temperature for BiFeO3 preparation was studied and the prepared photocatalysts were characterized through XRD, N2 adsorption at −196°C, TEM, XPS, Raman and UV–Vis DRS spectroscopy. The best photocatalytic activity was achieved with BiFeO3 calcined at 550°C. The influence of catalyst dosage and the role of the main oxidizing species was evaluated, evidencing the key role of h+ in the photooxidation reaction of As(III) to As(V). Moreover, the efficiency of the photocatalyst was also evaluated in the case of drinking water contaminated by arsenic. The results demonstrated that, despite the presence of dissolved salts in the drinking water, the photocatalyst maintained its activity. The results obtained in this work prove that BiFeO3 calcined at 550°C evidenced photocatalytic performances better than different photocatalyst formulations studied for the photooxidation of As(III) to As(V) under visible light.


Noviembre, 2023 | DOI: 10.1016/j.mssp.2023.107801

Reactividad de Sólidos

Integration of calcium looping and calcium hydroxide thermochemical systems for energy storage and power production in concentrating solar power plants

Carro, A; Chacartegui, R; Ortiz, C; Arcenegui-Troya, J; Perez-Maqueda, LA; Becerra, JA
Energy, 283 (2023) 128388

Show abstract ▽

 

Energy storage is a key factor in the development of renewables-based electrical power systems. In recent years, the thermochemical energy storage system based on calcium-looping has emerged as an alternative to molten salts for energy storage in high-temperature concentrated solar power plants. This technology still presents some challenges that could be solved by integrating the thermochemical energy storage system based on calcium hydroxide. This work studies a novel concentrated solar power system integrating calcium-looping and calcium hydroxide thermochemical energy storage systems. The results show that the combined use of hydration -dehydration cycles in the calcination-carbonation processes of the calcium looping for energy storage could partially solve the issue related to the multicyclic deactivation of calcium oxide. The improvement in the con-version of calcium oxide during carbonation is demonstrated experimentally when hydration-dehydration cycles are combined. Numerical simulations demonstrate the technical feasibility of the integrated process, with effi-ciencies ranging between 38-46%, improved with the increase in calcium oxide conversion in the carbonator, showing the potential of the proposed integration.


Noviembre, 2023 | DOI: 10.1016/j.energy.2023.128388

Materiales Coloidales

Mn2+-doped MgGeO3 nanophosphors with controlled shape and optimized persistent luminescence

González-Mancebo, D; Arroyo, E; Becerro, AI; Ocaña, M
Ceramics International, 49 (2023) 36791-36799

Show abstract ▽

 

Mn2+-doped MgGeO3 (MgGeO3:Mn2+) is an efficient persistent phosphor that emits red luminescence for long time after stopping excitation with UV light. For optical and biotechnological uses a precise control of particle size and shape is highly desired since these parameters may have a strong influence on the properties and suitability of phosphor materials for the intended applications. To the best of our knowledge, MgGeO3:Mn2+ has been synthesized by conventional solid-state-reaction, which yields particles of heterogeneous size and shape. Here, we report for the first time in the literature a salt-assisted method for the synthesis of MgGeO3:Mn2+ nanoparticles with uniform shape (nanorods) and a mean size of 350 nm x 99 nm. The rigorous study of the luminescence properties of the MgGeO3:Mn2+ nanorods revealed that whereas the optimum doping level for photoluminescence was 2.0 mol% Mn2+, the best persistent luminescence was attained with just 0.5 mol% Mn2+, which is ascribed to the different mechanisms of both luminescence processes. The optimum persistent nano-phosphor showed an intense red emission, which persisted at least 17 h after stopping the excitation. Such excellent properties make the developed nanophosphor an attractive candidate for use in optical and biotech-nological applications.


Noviembre, 2023 | DOI: 10.1016/j.ceramint.2023.09.008

 

 

 

 

 

icms