Synthesis and Characterization of Environmentally Friendly Chitosan–Arabic Gum Nanoparticles for Encapsulation of Oregano Essential Oil in Pickering Emulsion

The encapsulation of bioactive agents through the utilization of biodegradable nanoparticles is a topic of considerable scientific interest. In this study, microcapsules composed of chitosan (CS) and Arabic gum (GA) nanoparticles were synthesized, encapsulating oregano essential oil (OEO) through Pickering emulsions and subsequent spray drying. The optimization of hybrid chitosan and Arabic gum (CS–GA) nanoparticle formation was carried out via complex coacervation, followed by an assessment of their behavior during the formation of the emulsion. Measurements of the size, contact angle, and interfacial tension of the formed complexes were conducted to facilitate the development of Pickering emulsions for encapsulating the oil under the most favorable conditions. The chitosan–Arabic gum capsules were physically characterized using scanning electron microscopy and fitted to the Beerkan estimation of soil transfer (BEST) model to determine their size distribution. Finally, the OEO encapsulation efficiency was also determined. The optimum scenario was achieved with the CS–GA 1–2 capsules at a concentration of 2% wt, featuring a contact angle of 89.1 degrees, which is ideal for the formation of oil/water (O/W) emulsions. Capsules of approximately 2.5 m were obtained, accompanied by an encapsulation efficiency of approximately 60%. In addition, the hybrid nanoparticles that were obtained showed high biodegradability. The data within our study will contribute fundamental insights into CS–GA nanoparticles, and the quantitatively analyzed outcomes presented in this study will hold utility for forthcoming applications in environmentallySpanish Ministry of Science, grant number FPU17-0335

Dihydroxyacetone crystallization: Process, environmental, health and safety criteria application for solvent selection

Dihydroxyacetone is a good candidate to valorize the excess glycerol obtained as byproduct in biodiesel production. Crystallization is likely the key unit operation to obtain a high quality and pure dihydroxyacetone. The selection of an appropriate solvent for crystallization is not trivial and depends on multiple factors. At the present work a new solvent selection methodology, based on solvents relative comparisons, is described and applied to dihydroxyacetone crystallization as a case study. The procedure accounts not only for process factors such as solubility and yield, but also for cost, recycling, disposal, environmental, health and safety issues. Solubility and theoretical yield data for dihydroxyacetone in methanol, ethanol and 2-propanol were experimentally determined, while cost, life-cycle assessment, environmental, health and safety data of solvents were gathered from different bibliographic sources, software and databases. Among the solvents assessed, methanol resulted as the best overall choice for DHA crystallization. The methodology proved to be a suitable, simple and flexible procedure for solvent selection at the initial stages of the crystallization operation design, being able to be upgraded for advanced stages of the crystallization process development.Grupos de Investigación RNM332 y TEP21

Performance of Different Catalysts for the In Situ Cracking of the Oil-Waxes Obtained by the Pyrolysis of Polyethylene Film Waste

The author Lucía Quesada acknowledges the financial support provided by the Ministry of Education (Spain) through Research Grant FPU18/01293.Currently, society is facing a great environmental problem, due to the large amount of plastic waste generated, most of which is not subjected to any type of treatment. In this work, polyethylene film waste from the non-selectively collected fraction was catalytically pyrolyzed at 500 ◦C, 20 ◦C/min for 2 h, in a discontinuous reactor using nitrogen as an inert gas stream. The main objective of this paper is to find catalysts that decrease the viscosity of the liquid fraction, since this property is quite meaningful in thermal pyrolysis. For this purpose, the three products of catalytic pyrolysis, the gaseous fraction, the solid fraction and the liquid fraction, were separated, obtaining the yield values. After that, the aspect of the liquid fraction was studied, differentiating which catalysts produced a larger quantity of waxy fraction and which ones did not. The viscosity of these samples was measured in order to confirm the catalysts that helped to obtain a less waxy fraction. The results showed that the zeolites Y and the zeolites β used in this study favor the obtaining of a compound with a smaller amount of waxes than for example catalysts such as FCC, ZSM-5 or SnCl2.Ministry of Education (Spain) FPU18/01293Department of Chemical Engineering, University of Granad

Multi‑length Scale Approach to Investigate Cleaning of Food‑Derived Deposits Adhered to Hard Surfaces: Mixtures of Starch, Whey Protein, and Lard

Fouling, the accumulation of undesirable material on manufacturing equipment surfaces, poses a pervasive challenge in industrial processes. In the food industry, the complex interactions among these compounds can give rise to stubborn deposits that deviate from conventional cleaning protocols. In this work, the forces and removal mechanisms of model fouling agents composed of mixtures of starch, whey protein, and lard deposited on solid surfaces of relevant industrial interest (i.e. stainless steel, aluminium, and PTFE) are investigated using a multi-length scale approach, involving milli-manipulation and a lab-simulated Clean-In-Place (CIP) system. The forces involved in the removal process, the types of failure observed when the deposits are subjected to shear stress (adhesive, mixed, or cohesive), and the performance of the CIP system are systematically analysed as a function of the cleaning treatments applied. For stainless steel surfaces, alkaline treatment seems to facilitate the cleaning of lard and starch deposits, while the whey foulant removal tends to be more effective using hot water under the conditions tested. Hot water is effective for stainless steel and PTFE surfaces, reducing the mechanical shear stress required, while the alkaline treatment demonstrated superior efficacy for aluminium surfaces. These findings emphasise the importance of customising cleaning protocols for CIP optimisation

Estudio cinético comparaado de la utilización de enzimas libres e inmovilizadas : isomerización fructosa-glucosa

Se estudia la cinética de la isomerizacion enzimatica fructosa-glucosa en fase homogénea con la enzima en disolución, en un reactor de lecho fijo con la enzima retenida en la matriz de un gel y en un reactor de fibra hueca con la enzima retenida en la carcasa de un modulo de fibra hueca. para la interpretación de los resultados se ha desarrollado un modelo de la interacción entre la cinética y la transferencia de materia en el interior de las partículas. Se propone una expresión para la constante de equilibrio en función de la temperatura y una ecuación cinética en función de la concentración total de hexosas y de la temperatura. También se propone una ecuación para el calculo del factor de efectividad en cinéticas tipo michaelis-mente

Cursos de nivel cero para las titulaciones de primer ciclo de ciencias

Dentro de la política de apoyo a las iniciativas que en materia docente debe realizar la Universidad, en el ámbito de la innovación y para conseguir los niveles de calidad y excelencia necesarios para una adecuada formación y capacitación de los estudiantes, resulta muy importante ofrecer herramientas que ayuden al estudiante a completar o adquirir conceptos previos para así poder después conectarlos con la nueva información que están recibiendo o van a recibir durante su primer año de titulación. En este sentido, la elaboración de unos cursos de nivel cero de las materias básicas: Matemáticas, Física, Química, Biología y Geología que, mediante el uso de la plataforma docente SWAD (Sistema Web de Apoyo a la Docencia: https://swad.ugr.es), permitirá que, antes del comienzo del curso académico, aquellos alumnos que lo consideren necesario o imprescindible, puedan trabajar con aquellas asignaturas básicas en las que sus conocimientos sean más deficientes o consideren que necesitan revisar. Esto ayudará a reducir el número de abandonos en el primer curso de la titulación ya que su realización permite que el alumno adquiera una base suficiente para abordar los contenidos de las asignaturas, facilitándoles la asimilación y comprensión de los contenidos de las misma

Orientaciones profesionales en el área de la ingeniería química

Desde el curso académico 2003/04, un grupo de profesores de la Titulación de Ingeniero Químico, venimos desarrollando un Plan de Acción Tutorial dirigido a todos los alumnos de la Titulación. Con dicho plan se pretende dar una orientación a los alumnos en diferentes aspectos tales como la Universidad, su Facultad, órganos de representación, becas, investigación, orientación académica y profesional. Para alcanzar este último aspecto se han organizado Jornadas informativas como 'El Ingeniero Químico y el Desarrollo de su Profesión' a fin de conseguir que los alumnos de nuevo acceso conozcan su Titulación no sólo desde el aspecto académico sino también profesional y con unas 'Jornadas Profesionales de Ingeniero Químico', dirigidas a los alumnos de últimos cursos, para conseguir que adquieran una visión clara sobre la situación del mercado laboral, acceso y actividades de cada sector relacionadas con la Ingeniería Químic

Surface and thermodynamics properties of commercial fatty-alcohol ethoxylate surfactants

Supplementary data to this article can be found online at https://doi.org/10.1016/j.molliq.2023.121396.The present study provides the surface and thermodynamic properties data of commercial fatty-alcohol ethoxylate surfactants (FAEs) at different temperatures (25–60 C). These compounds are a mixture of fatty-alcohol ethoxylate oligomers with different degree of ethoxylation (2.6–11) and length of the alkyl chain (C10-C18). In this work, we analyzed determinate the water content by the Karl-Fisher method and measured the surface tension using the Wilhelmy plate method. In addition, we studied the effect of their structural parameters (degree of ethoxylation and length of alkyl chain) and the temperature on the changes of the thermodynamic functions (Gibbs free energy, enthalpy, and entropy) for the processes of adsorption and micellization. It was found an exponential decrease of the critical micellar concentration (CMC) in molar scale with the length alkyl chain of the fatty-alcohol ethoxylate surfactants, and the CMC values and thermodynamic parameters agree with those values found in literature for pure compounds. Moreover, the micellization entropy increases with the degree of ethoxylation of the surfactant.Funding for open access charge: Universidad de Granada / CBUAJunta de Andalucía predoctoral grant Programa de Incentivos a los Agentes del Sistema Andaluz del Conocimiento 2008-201