Remoción de Cu (II) de aguas ácidas usando biomasa de las cáscaras de coco

Conferencia de la 20th LACCEI International Multi-Conference for Engineering, Education, and Technology: “Education, Research and Leadership in Post-pandemic Engineering: Resilient, Inclusive and Sustainable Actions”. hybrid event, Boca Raton, Florida- USA, junio 18 - 22.La contaminación del agua por metales pesados generados por la industria minera es un problema ambiental. El uso de materiales de desecho orgánicos para tratar estas aguas ofrece una alternativa a las tecnologías de tratamiento existentes. El presente trabajo de investigación reporta la remoción de cobre de aguas ácidas utilizando biomasa de cáscara de coco (BCC). Las muestras de agua a tratar fueron recolectadas de las redes de drenaje de la laguna de Huascacocha, la concentración de Cu detectada fue de 3,26 mg/L, valor que supera los Estándares de Calidad Ambiental establecidos por la legislación peruana. En un sistema discontinuo se evaluó la influencia del tiempo de contacto y tamaño de partícula del BCC sobre el porcentaje de remoción de Cu (% R). Se logró un % R mayor de 92,67 con un tamaño de partícula de 0,21 mm y un tiempo de contacto de 60 min. Del análisis estadístico se concluye que las dos variables en estudio, a sí como su interacción, influyen significativamente en el % R. De los resultados presentados se puede decir que la BCC es una alternativa ecológica y factible para la remoción de Cu (II ) de aguas ácidas.Campus Huancay

Arabica‑cofee and teobroma‑cocoa agro‑industrial waste biosorbents, for Pb(II) removal in aqueous solutions

Agro-industrial waste biosorbents of arabica–cofee (WCA) and theobroma–cocoa (WCT) have been characterized and tested to remove Pb(II) from aqueous media. The maximum adsorption capacity of WCA and WCT (qmax = 158.7 and 123.5 mg·g−1, respectively) is comparable or even higher than for several other similar agro-industrial waste biosorbents reported in the literature. Structural and morphological characterization were performed by infrared spectrometry with Fourier transform (FT-IR), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), and charge measurements at the zero point charge (pHPZC). Both biosorbents, WCA and WCT, show cracked surfaces with heterogeneous plates which ones include functional adsorption groups such as OH, C = O and C-O-C. Optimal Pb(II) adsorption occurs for a pH between 4 and 5 at [WCA] and [WCT] dose concentrations of 2 g·L−1. We found that the adsorption process follows pseudo-second order kinetics with a rapid growth rate (almost six times larger for WCA than for WCT), basically controlled by the chemisorption process. The regeneration of both biosorbents was carried out in an eluent of 0.1M HNO3 and they can be eficiently reused up to 5 times.Campus Lima Centr

The contribution of meteorological parameters and the COVID-19 partial lockdown on air quality in Rio de Janeiro, Brazil

This study evaluated the pollutant levels (NO2, SO2, CO, and O3), air quality index (AQI) and the influence of meteorological variables and coronavirus disease (COVID-19) pandemic on the air quality in Rio de Janeiro. The data set used comprises periods before (March-April, 2019) and during pandemic (March-April, 2020). According to the AQI results, on most days, the air quality was ranked as “good”. Brazilian air quality standards for SO2, O3, and NO2 were not exceeded in any of the monitoring stations during partial lockdown, while CO exceeded in all periods in one site due to industrial emission. Comparing both periods, descriptive statistics for the meteorological parameters presented no differences, which suggests similar conditions. However, when evaluated week by week in 2020, weather conditions presented some differences that probably affected pollutant concentrations. The correlations between O3 and NO2 and some meteorological parameters indicate that variations in both favored ozone formation, since it is a photochemical process favored by temperature and solar radiation and that, in Rio de Janeiro, low NO2 concentrations lead to increased O3. The improvements on air quality during the partial lockdown may be attributed mainly to a reduction on emission sources rather than weather conditions.Campus Lima Centr

Antifungal effect from zingiber officinale, aloe vera and trichoderma sp. for control of moniliophthora roreri in theobroma cacao in Huánuco, Peru

Theobroma cacao is the main raw material to produce chocolate, as well as for use in the food, cosmetic, and pharmaceutical industries. However, Moniliophthora roreri is one of the most destructive fungal diseases and the main limiting of cacao production worldwide. Thus, this work aimed to assess the inhibitory effect of extracts of Zingiber officinale (T1) and Aloe vera (T2), and Trichoderma harzianum + Bacillus subtillis. (T3) on Moniliophthora roreri infection in Theobroma cacao; in addition, a control (T4) was also evaluated. Each treatment was applied to six plants of cacao. Incidence of monilia infection and fruit weight were monitored every 15 days (in total four periods) after the application of the treatment by spray. Significant differences (P<0.05) were found among treatments for incidence. It was observed that spraying entire cacao trees after two times (approximately 30 days) showed a reduction of monilia infection. After all periods, T1, T2, and T3 showed an incidence of monilia infection by 20.5, 17.7, and 14.9% respectively, compared to cultural control of 41.1%. This reduction of moniliasis infection translates into an increase in fruit weight average for T3 (8.4 kg), T2 (7.3 kg), and T1 (6.9 kg). In contrast, in the control (T3), the fruit weight average decreased by 5.3 kg. Biological control showed efficient management of pathogens as M. roreri. It is recommended to use such antifungal (Aloe vera) spray over at least 120 days which would decrease infection incidence even more.Campus Lima Centr