Person:
Vera Cabezas, Luisa Mayra

Birth Date

1970-07-20

ORCID

0000-0002-0240-9147

Scopus Author ID

58812366700

Afiliación

Universidad de Cuenca, Cuenca, Ecuador
Universidad de Cuenca, Facultad de Ciencias Químicas, Cuenca, Ecuador
Universidad de Cuenca, Departamento de Recursos Hídricos y Ciencias Ambientales, Cuenca, Ecuador
Universidad de Cuenca, Centro de Estudios Ambientales, Cuenca, Ecuador
Universidad de Cuenca, Departamento de Química Aplicada y Sistemas de Producción, Cuenca, Ecuador

País

Ecuador

Organizational Units

Organizational Unit

Facultad de Ciencias Químicas

Fundada en 1955 como la Escuela de Química Industrial, la facultad ha sido un pilar fundamental en la formación de profesionales altamente capacitados, comprometidos con el desarrollo de la ciencia, la educación y el bienestar social. La Facultad de Ciencias Químicas pone a consideración su trabajo académico, investigativo y de vinculación con la sociedad, desarrollado a través de la práctica de una docencia de calidad, investigación e innovación en su área de estudio. Desde su oficio de conocimiento se permite contribuir a la sociedad con cuatro carreras: Bioquímica y Farmacia, Ingeniería Química, Ingeniería Ambiental e Ingeniería Industrial. Su carta de presentación en la Academia, la coloca como una dependencia dinámica, donde confluye la solidez de una trayectoria de más de sesenta años. Aquí se trabaja en una continua formación de pregrado y posgrado de la más alta calidad, mediante la mejora continua con la innovación y a la vanguardia de las ciencias químicas.

Job Title

Profesor (T)

Last Name

Vera Cabezas

First Name

Luisa Mayra

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Now showing 1 - 10 of 18

Efectos de la ultrafiltracion sobre la fitotoxicidad de efluentes primarios y secundarios de la depuración de aguas residuales urbanas
(2016) González, Ea; Pérez Donato, Jorge A; Vera Cabezas, Luisa Mayra; Bravo S., La; Delgado, Sa
The clean / reclaimed waste water has become an important alternative water resources as part of sustainable use and management of water, especially in arid areas with deficits in natural resources. One application of interest is the agricultural irrigation industry that requires large amounts of water. The classic stages of primary and secondary biological treatment supply effluents with limited applications for irrigation, but can be improved significantly if such effluents undergo a process of ultrafiltration membranes. This paper presents the results of a study correlating the physical and chemical quality with phytotoxic properties, parameters in primary and secondary effluents and the effect of the ultrafiltration membrane in such effluents are analyzed. In each sample was measured: conductivity, turbidity, total organic carbon, soluble proteins, polysaccharides, chemical oxygen demand and ions of Na+ , K+ , Ca2+, Mg2+, B3+, Fand Cl- . Criteria phytotoxicity were evaluated by Lactuca sativa L. Biomarker is concluded that phytotoxicity conductivity and are interdependent to evaluate the toxic effect treatment processes for wastewater parameters. Moreover, the Na+ and Clions may play a role in the permeates phytotoxic obtained when subjected to ultrafiltration primary and secondary effluents.
Valoración físico-química y fitotóxica de las aguas residuales depuradas/regeneradas destinadas al riego agrícola. Revista de toxicología
(2015) Bravo Sanchez, Luis Ramon; Pérez Donato, Jo A.; Delgado Díaz, Sergio; González Cabrera, Ernesto; Vera Cabezas, Luisa Mayra
The most widespread application of reuse of treated / reclaimed domestic wastewater is agricultural irrigation. The common regulations on quality of reclaimed water for reuse contemplated physicochemical and biological parameters to minimize health risks, but rarely taken into account phytotoxic parameters that may be limiting for agricultural applications. The physicochemical and phytotoxic parameters change to advance the degree of purification / regeneration of wastewater, so it is of interest to know what stage of the installation provides adequate water for irrigation. This paper presents a correlation study of phytotoxicity with physicochemical parameters in water samples taken at the end of each of the stages of conventional treatment of domestic sewage, including biological reactor activated sludge treatment and tertiary sand filtration, chlorination, filtration cartridge and desalination by electrodialysis reversal. In each sample was measured. Chemical oxygen demand, pH, conductivity, organic carbon, total phosphorus, soluble proteins and ions of Na, K, Ca, Mg, B, F and Cl criteria phytotoxicity were evaluated by Lactuca sativa biomarker.Results showed significant reductions in physicochemical parameters of electrodialysis process, while the effects of phytotoxicity showed reductions in the processes before the final stage of electrodialysis.We conclude that the physico-chemical, together with the biomarker parameters are aspects of practical interest that relates the type of treatment with physical-chemical
A new approach for scaling up fixed-bed adsorption columns for aqueous systems: a case of antibiotic removal on natural adsorbent
(2022) Juela Quintuña, Diego Marcelo; Vera Cabezas, Luisa Mayra; Cruzat Contreras, Christian Américo; Astudillo Alemán, Ana Lucía; Vanegas Peña, María Eulalia
The scaling up of adsorption columns is a crucial step toward the removal of emerging pollutants from domestic and industrial wastewaters. In this study, a fixed-bed column to remove sulfamethoxazole packed with sugarcane bagasse was scaled up from laboratory (DL = 2.2 cm) to pilot unit (DP = 4.4 cm) using a scaling factor (K = 2). In addition to the basic similarity rules for scaling, three new criteria were proposed for the mass adsorbent, flow rate, and bed volume. Then, three lab-scale tests at flow rate of 5 mL/min and bed heights of 15, 25, and 35 cm were transferred to the pilot-scale column at flow rate of 20 mL/min and bed heights of 30, 50, and 70 cm, respectively. The breakthrough curves and the fixed-bed parameters (residence time tR, saturation time ts, adsorption capacity qe, volume of solution treated Vef, and removal percentage %R) obtained in both scales were compared to define their effect with the increase of scale. Finally, a mechanistic model was proposed to predict the breakthrough curves in both columns. The results exhibited that the breakthrough curves in the pilot-scale prolonged in time with higher breakthrough and saturation times than the laboratory breakthrough data. Additionally, tR, ts, and Vef changed in function of the K value used: ts and tR doubled their value in the pilot column or ; Vef was eight times higher in the pilot column than the lab-column or ; qe and %R remained constant in both scales; these results were corroborated with the predicted breakthrough curves. Besides, the mechanistic model predicted with great precision the breakthrough data in both scales (R2>0.9), which means that the model can be used confidently for scaling up purposes. This study demonstrated new criteria which can be easily applied to scale up adsorption columns whit results that showed a correlation between both scales.
Modeling and computational fluid dynamic simulation of acetaminophen adsorption using sugarcane bagasse
(2021) Vera Cabezas, Luisa Mayra; Juela Quintuña, Diego Marcelo; Cruzat Contreras, Christian Américo; Vanegas Peña, María Eulalia
Evaluación toxicológica de soluciones acuosas de ibuprofeno mediante bioensayos con Artemia salina, Allium schoenoprasum L y Lactuca sativa
(2018) Saetama Guallpa, Maria Veronica; Vera Cabezas, Luisa Mayra; Vanegas Peña, María Eulalia; Cruzat Contreras, Christian Américo; Brazales Quizhpe, Diana Esperanza
Drugs are considered within the so-called emerging pollutants, so it is important to investigate the toxic effects they can produce in the environment. The aim of this study was to determine the toxic effect of aqueous solutions of ibuprofen on an aquatic organism Artemia salina and the seeds of Allium schoenoprasum L and Lactuca sativa. The toxicity tests were carried out by exposing the test organisms to concentrations of aqueous ibuprofen solutions of 20, 10, 5, 2, 1 and 0.5 mgL-1. The percentage of mortality for Artemia salina and the elongation of the radicle and hypocotyl for the seeds were determined. The highest mortality percentage occurred at the concentration of 20 mgL-1, the calculated LC50 was 17.386 mgL-1. A low toxic effect was present in the germination of the seeds of Allium schoenoprasum L. There was inhibition in the elongation of the radicle and hypocotyl in seeds of Allium schoenoprasum L and a stimulation effect in the elongation of the radicle and hypocotyl of the seeds of Lactuca sativa. The highest inhibition effect was presented at 1 and 20mgL-1 and the highest stimulation at 20 mgL-1.
Nanofiltración/ósmosis inversa en la separación de fármacos de efluentes
(2021) González, Enrique; Vera Cabezas, Luisa Mayra; Astudillo Alemán, Ana Lucía; Cruzat Contreras, Christian Américo; Solórzano, A.
Membrane separation processes can be an effective barrier against pharmaceuticals and other organic compounds present in water sources. This investigation presents the results of the separation of ciprofloxacin (CIPRO) and sulfamethoxazole (SULFA) in aqueous solution with nanofiltration membranes (NF) and reverse osmosis (OI) at a concentration in the feed of 5 mg / L and the influence of pH on separation mechanisms. With RO membranes, rejection was 100% for CIPRO and greater than 98% for SULFA at the studied pH. For the NF, the pH had influences on the separation of the SULFA, obtaining in the rejection 73.7% at pH 5 and at pH 7 and 9 greater than 94%. In the case of CIPRO, rejection percentages greater than 91% were obtained. The rejection obtained with the solution of the mixture of the two drugs shows no change since the percentages of rejections are very close to the results obtained in the study of the drugs separately. The transmembrane pressure did not influence the rejection of the drugs.
Low-cost crop waste biosorbent technology for removing toxics and pollutants from wastewater
(Springer, 2020) Vera Cabezas, Luisa Mayra; Cruzat Contreras, Christian Américo; Vanegas Peña, María Eulalia
Estudio experimental y simulación dinámica de la adsorción de Cd+2 y Pb+2 utilizando cáscara de cacao en columna de lecho fijo
(2022) Juela Quintuña, Diego Marcelo; Vera Cabezas, Luisa Mayra; Astudillo Ochoa, Sonia Margoth
The use of biomass as an adsorbent constitutes a potential alternative for the removal of heavy metals present in industrial wastewater, which represents a high risk for the environment. In this work, the adsorption of Pb+2 and Cd+2 was performed using the cocoa shell as adsorbent in columns, and the dynamic simulation of the process using the Aspen Adsorption® V10 software, in order to validate the simulation results and those obtained experimentally. The simulator and experimental rupture curves converge in almost the entire trajectory, with slight variations in the final stretch of the curve, with the rupture times coinciding for both metals, giving correlation coefficients (R2) of 0.984 and 0.998 for Pb+2 and Cd+2 respectively, as well as error values (SSE) less than 5%. The effect produced by the variation of the height of the bed and the flow rate in the rupture curves was analyzed, as the bed height increases and the flow rate decreases, the rupture time increases, favoring the adsorption of both metals. The results of this research show the importance of the use of Aspen Adsorption® software in the biosorption process, due to the similarity with experimental results, providing its use saving time and resources.
Evaluación del poder biosorbente de la hoja de maíz en la remoción de metales pesados
(2020) Astudillo Ochoa, Sonia Margoth; Castro Nube, Cecilia; Astudillo Zuñiga, Jorge Israel; Vera Cabezas, Luisa Mayra
Effects of ultrafiltration on the phytotoxicity of primary and secondary effluents from urban wastewater treatment [Efectos de la ultrafiltración sobre la fitotoxicidad de efluentes primarios y secundarios de la depuración de aguas residuales urbanas]
(Asociación Española de Toxicología, 2016-01-01) Vera Cabezas, Luisa Mayra
The clean / reclaimed waste water has become an important alternative water resources as part of sustainable use and management of water, especially in arid areas with deficits in natural resources. One application of interest is the agricultural irrigation industry that requires large amounts of water. The classic stages of primary and secondary biological treatment supply effluents with limited applications for irrigation, but can be improved significantly if such effluents undergo a process of ultrafiltration membranes. This paper presents the results of a study correlating the physical and chemical quality with phytotoxic properties, parameters in primary and secondary effluents and the effect of the ultrafiltration membrane in such effluents are analyzed. In each sample was measured: conductivity, turbidity, total organic carbon, soluble proteins, polysaccharides, chemical oxygen demand and ions of Na+, K+, Ca2+, Mg2+, B3+, F- and Cl-. Criteria phytotoxicity were evaluated by Lactuca sativa L. Biomarker is concluded that phytotoxicity conductivity and are interdependent to evaluate the toxic effect treatment processes for wastewater parameters. Moreover, the Na+ and Cl- ions may play a role in the permeates phytotoxic obtained when subjected to ultrafiltration primary and secondary effluents.