The main objective of this study was to analyze the efficiency of CWs for purifying swine wastewater in order to reduce its pollutant load. The system included a pretreatment module (raw swine wastewater tank, phase separator, and settlement tank), and three constructed wetlands connected in series and planted with Phragmites australis and Suaeda vera. Three treatment cycles were carried out with a total hydraulic retention time in the wetland of 21 days for each cycle. Pig slurry samples were collected in triplicate after each treatment module, and physical–chemical analyses were performed. The results showed that the phase separator decreased the suspended solids, turbidity, and the chemical oxygen demand in the treated swine wastewater. The system enabled considerable nitrogen reductions (Kjeldahl nitrogen, NH₄⁺, and organic nitrogen), and the highest removal was reported in the wetlands. However, the cations and anions showed different efficiencies. In some cases (Ca, Mg, and Na), the final concentrations were increased, which could be explained by their release from the substrate; however, there were no statistical differences among the CW effluents and the raw pig slurry. Therefore, the integral pig slurry treatment system with constructed wetlands increased the quality of the treated swine wastewater and thus can be used for its sustainable agronomic valorization. This thereby enables savings in inorganic fertilizers and irrigation water.

The use of fertilizers coated with insoluble organic compounds is a promising approach for enhancing fertilizer efficiency and crop yield. Silk sericin (SS) is a protein with a high potential for the development of materials oriented toward fertilizer coating and soil amendment because of its biodegradability and the fact that it represents an important source of nitrogen for plants. Thus, this study proposes the design and evaluation of a novel SS-based multilayer coating for fertilizer granules. A pan-coating process was applied to form two distinct layers on the granules: an inner layer made of silk sericin/polyvinyl alcohol, SS/PVA (50/50 w/w), which has low solubility and porosity, and an outer hydrogel layer of SS/PVA with carboxymethyl cellulose CMC (SS/CMC/PVA 45/25/30 w/w/w). Scanning electron microscopy (SEM) was employed for the morphological characterization of the coated fertilizer (CF), examining both the cross-section and surface, while SEM with energy-dispersive X-ray spectroscopy (SEM/EDS) was used to analyze the chemical composition of the surface. The ability of the coating to reduce the nutrient-release rate was studied using water- and soil-release tests. Furthermore, its performance was evaluated in in vivo assays using jalapeño bell pepper (Capsicum annum) plants. The results revealed that the structure and composition of the multilayer coating significantly influenced its ability to delay nutrient release in both water and soil. Moreover, the inclusion of SS in the coating potentially contributed to the increased nitrogen content in the soil, thereby improving plant growth rates.

Se describe una propuesta para fortalecer el énfasis profesional del currículo de ingeniería química en la Universidad Pontificia Bolivariana (UPB) en Colombia. Tanto las áreas del saber como los campos de acción asociados a la ingeniería química han variado y se han multiplicado en las últimas décadas, impulsando al mundo académico a renovar el proceso de formación de los futuros profesionales. Es por ello que la Facultad de Ingeniería Química de la UPB ha diseñado una estrategia que, mientras especializa al estudiante en un campo específico del conocimiento y el desempeño de la ingeniería química, vincula la formación profesional con la de postgrado. Se trata de un conjunto de 15 créditos, denominado Ruta de Formación Optativa, donde 6 créditos corresponden a cursos de carrera y 9 créditos a cursos de postgrado de la Escuela de Ingenierías. Se presentan las nueve rutas diseñadas, que configuran nueve perfiles profesionales y ocupacionales específicos, entre los cuales el estudiante puede elegir, fortaleciendo su autonomía, a la vez que se promueve y se facilita su educación de alto nivel.

Electrophoretic deposition (EPD) of semiconducting TiO2_Aeroxide®P25 and TiO2_Commercial on stainless steel was performed for the fabrication of photoanodes with potential use in the photoelectrocatalytic decolorization of the azo dye Red_Reactive_239 (RR239). The influence of the EPD parameters on the homogeneity and mechanical stability of the deposits was studied. In addition, the effect of the composition of the photocatalytic phases and the optical bandgap of the semiconductors on the decolorization performance was analyzed. The fabrication conditions of the electrodes were established, in a first experimental stage, by varying the voltage application mode (pulsed and non-pulsed) at 10 V and a deposition time of 30 s. Subsequently, a variation of the heat treatment temperature (250 and 350 °C) necessary for the stabilization of the deposit was carried out. Once the voltage application mode and the heat treatment temperature were defined, a second step was performed to establish the EPD time in a range between 10 and 60 s. When the voltage was applied pulsed, the deposits were uniform and homogeneous. The use of TiO2_Aeroxide®P25 and TiO2_Commercial allowed to reach decolorization percentages higher than 80 % when the EPD was performed at 1.1 V for 1 h irradiating the anode with UV light (λ = 365 nm). EPD conditions and the temperature of the thermal treatment showed an appreciable effect on the physical characteristics of the deposits and their effectiveness as photoanodes for RR239 decolorization. Suitable conditions for the fabrication of the photoanodes were achieved, being TiO2_Commercial an alternative replacement for TiO2_Aeroxide®P25 in photoelectrocatalytic applications for RR239 decolorization under the evaluated conditions due to its comparable performance and low cost. Se realizó la deposición electroforética (EPD) de los semiconductores TiO2_Aeroxide®P25 y TiO2_Comercial sobre acero inoxidable para la fabricación de fotoánodos con potencial uso en la decoloración fotoelectrocatalítica del colorante azoico Rojo_Reactivo_239 (RR239). Se estudió la influencia de los parámetros de la EPD sobre la homogeneidad e integridad de los depósitos. Asimismo, se analizó el efecto de la composición de las fases fotocatalíticas y el ancho de la banda prohibida óptica de los semiconductores en el rendimiento de la decoloración. Las condiciones de fabricación de los electrodos se establecieron en una primera etapa experimental variando el modo de aplicación del voltaje (pulsado y no pulsado) a 10 V y un tiempo de deposición de 30 s. Posteriormente, se varió la temperatura del tratamiento térmico (250 y 350 °C) necesario para la estabilización del depósito. Definido el modo de aplicación del voltaje y la temperatura del tratamiento térmico, se realizó una segunda etapa para establecer el tiempo de la EPD en un rango entre 10 y 60 s. Cuando el voltaje se aplicó por pulsos, los depósitos resultaron más uniformes y homogéneos. El uso de TiO2_Aeroxide®P25 y TiO2_Comercial permitió alcanzar porcentajes de decoloración superiores al 80 % cuando la EPD se ejecutó a 1,1 V durante 1 h irradiando el ánodo con luz UV (λ.= 365 nm). Las condiciones de la EPD y la temperatura del tratamiento térmico mostraron un efecto apreciable sobre las características físicas de los depósitos y su eficacia como fotoánodos para la decoloración de RR239. Se lograron las condiciones adecuadas para la fabricación de los fotoánodos, siendo el TiO2_Comercial una alternativa de reemplazo del TiO2_Aeroxide®P25 en aplicaciones fotoelectrocatalíticas para la decoloración de RR239 bajo las condiciones evaluadas debido a su rendimiento comparable y bajo costo.