Jesús Álvarez Sánchez - Academia.edu (original) (raw)

Papers by Jesús Álvarez Sánchez

Research paper thumbnail of Macromol. Symp. 283-284

Macromolecular Symposia, 2009

Cover: The inaugural US-Mexico Symposium on Advances in Polymer Science, MACROMEX 2008, took plac... more Cover: The inaugural US-Mexico Symposium on Advances in Polymer Science, MACROMEX 2008, took place in Los Cabos, Mexico. This first bi-national conference was the result of a joint effort of the Mexican Polymer Society and the Polymer Chemistry Division of the American ...

Research paper thumbnail of Modification of Thin Film Composite Membrane by Chitosan–Silver Particles to Improve Desalination and Anti-Biofouling Performance

Membranes

Reverse osmosis (RO) desalination is a technology that is commonly used to mitigate water scarcit... more Reverse osmosis (RO) desalination is a technology that is commonly used to mitigate water scarcity problems; one of its disadvantages is the bio-fouling of the membranes used, which reduces its performance. In order to minimize this problem, this study prepared modified thin film composite (TFC) membranes by the incorporation of chitosan–silver particles (CS–Ag) of different molecular weights, and evaluated them in terms of their anti-biofouling and desalination performances. The CS–Ag were obtained using ionotropic gelation, and were characterized by Fourier transform infrared spectroscopy (FTIR), high-resolution scanning electron microscopy (HR-SEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA) and dynamic light scattering (DLS). The modified membranes were synthetized by the incorporation of the CS–Ag using the interfacial polymerization method. The membranes (MCS–Ag) were characterized by Fourier transform infrared spectroscopy (FTIR), atomic forc...

Research paper thumbnail of NANOFILTRATION MEMBRANES, PREPARED VIA INTERFACIALPOLYMERIZATION, DOPED WITH ZnO NANOPARTICLES: EFFECT ONPERFORMANCE

Revista Mexicana de Ingeniería Química

Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo int... more Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo intemperizados en suelos y sedimentos (Biodegradation modeling of sludge bioreactors of total petroleum hydrocarbons weathering in soil and sediments)

Research paper thumbnail of Modification and characterization of TFC membranes with Ag nanoparticles: application in seawater desalination

Research paper thumbnail of Effect of Temperature on Diluate Water in Batch Electrodialysis Reversal

Separations, 2021

A high percentage of the agricultural wells in the state of Sonora are overexploited, thus genera... more A high percentage of the agricultural wells in the state of Sonora are overexploited, thus generating a significant degree of saline intrusion and abandonment by nearby communities. In this paper, the effect of temperature on the final concentration of diluted water was evaluated with variations in voltage and input concentration in a batch electrodialysis reversal (EDR) process in order to find the optimal operating conditions, with an emphasis on reducing the energy consumption and cost of desalinated water. Thirty-six samples were prepared: eighteen samples of 2000 mg/L total dissolved solids (TDS) and eighteen samples of 5000 mg/L TDS; brackish well water of 639 mg/L TDS and synthetic salt were mixed to obtain these concentrations. Three different temperatures (25, 30, and 35 °C) and two different voltages (10 and 20 V) were tested for each sample after evaluating the limiting current density. The best salt removal occurred in the 20 V sets, with 18.34% higher removal for the 20...

Research paper thumbnail of Using Desalination to Improve Agricultural Yields: Success Cases in Mexico

Desalination and Water Treatment, 2018

Water scarcity is a global problem, motivating growth and development of new technologies for wat... more Water scarcity is a global problem, motivating growth and development of new technologies for water treatment, reuse and desalination. For many arid regions in Mexico, especially in the northwest, agriculture is an important economic activity. The Yaqui Valley in Sonora, Mexico, faces problems related to aquifer overexploitation and saline intrusion, which have increased salt concentration in well water to 2000-9000 mg/L total dissolved solids (TDS) and led to soil salinization and low crop yields. This work evaluates the effect of TDS in irrigation water on crop yield. A 150 m 3 /d desalination plant was used, consisting of 12 SWC4B-MAX membrane modules, with 98% rejection and 75% recovery. Two crops were irrigated with control (4000 mg/L) and desalinated water (200 mg/L). Sorghum (Sorghum) had yields of 7.9 and 8.8 ton/ha, whereas tomatillo (Physalis philadelphica) had yields of 30.82 and 35.88 ton/ha, respectively. Evidently, the desalination process influences agricultural yields.

Research paper thumbnail of Desalación por ósmosis inversa y su aprovechamiento en agricultura en el valle del Yaqui, Sonora, México

Tecnologia y Ciencias del Agua, 2016

Sonora, situado al noroeste de Mexico, ocupa el segundo lugar en cultivos de riego en el pais. Lo... more Sonora, situado al noroeste de Mexico, ocupa el segundo lugar en cultivos de riego en el pais. Los problemas de disponibilidad de los recursos hidricos, principalmente para agricultura en ese estado, se deben a la alta concentracion de sales en los pozos, que van desde 2 000 hasta 5000 mg/l de solidos disueltos totales (SDT). Estos altos valores de SDT son atribuidos a efectos de intrusion salina (Devora, Gonzalez, & Saldivar, 2009), al tener una excesiva explotacion del manto acuifero (Conagua, 2011). Sin embargo, el uso de tecnologias de desalacion y modelos de prediccion del proceso permiten aprovechar el recurso de manera optima tanto en agua producto como en el rechazo. Es por esto que el objetivo es definir un modelo matematico de simulacion para la prediccion de la operacion de una planta desaladora de osmosis inversa alimentada por agua salobre, validando que el agua producto cumpla con los limites permisibles para su uso en agricultura. Con motivo de validar el modelo, el e...

Research paper thumbnail of Sistema De Adquisición De Datos De Bajo Costo Para Un Invernadero Basado en Tecnología De Acceso Libre

Resumen En este trabajo se presenta un sistema de adquisicion de datos desarrollado para un inver... more Resumen En este trabajo se presenta un sistema de adquisicion de datos desarrollado para un invernadero clasico cenital que se basa en el microcontrolador ESP826612E y la computadora de bolsillo Raspberry Pi 3, los cuales son plataformas de hardware libre. Los parametros obtenidos son la temperatura y la humedad. En el metodo se incluye la integracion de los componentes al sistema de adquisicion de datos, en particular el sensor de temperatura y humedad (DHT11), el servidor (Mosquitto y Node-RED), utilizando los protocolos de comunicacion inalambrica (WiFi y MQTT). Los resultados muestran la factibilidad para utilizar un conjunto de dispositivos inalambricos para la integracion de un sistema donde se requiere procesar informacion de manera remota, en este caso un invernadero. Palabras Claves: Adquisicion de datos, invernadero, mosquitto, Node-RED, Raspberry Pi. LOW COST DATA ACQUISITION SYSTEM FOR A GREENHOUSE BASED ON FREE ACCESS TECHNOLOGY Abstract A data acquisition system for a ...

Research paper thumbnail of Influence of different reactor types on Nannochloropsis oculata microalgae culture for lipids and fatty acid production

Journal of the American Oil Chemists' Society, 2021

Research paper thumbnail of Effect of seawater variability on endemic bacterial biofouling of a reverse osmosis membrane coated with iron nanoparticles (FeNPs)

Chemical Engineering Science, 2020

Biofouling study of endemic bacteria on iron nanoparticle coated membrane. The Sea of Cortez wate... more Biofouling study of endemic bacteria on iron nanoparticle coated membrane. The Sea of Cortez water has a high potential to biofoul the Reverse Osmosis membranes. Physicochemical parameters values of El Sol Beach water delay biofilm growth. Temperature, pH and dissolved oxygen affect directly the biofilm growth. Temperature, pH and dissolved oxygen improve iron nanoparticle coating effectiveness.

Research paper thumbnail of Uptake of copper from acid mine drainage by the microalgae Nannochloropsis oculata

Environmental Science and Pollution Research, 2019

The removal of heavy metals from acid mine drainage is a key factor for avoiding damage to the en... more The removal of heavy metals from acid mine drainage is a key factor for avoiding damage to the environment. The microalga Nannochloropsis oculata was cultured in an algal medium with 0.05, 0.1, 0.15, 0.2, and 0.25 mM copper under completely defined conditions to assess its removal capacity; the effects of copper on the cell density and lipid productivity of N. oculata were also evaluated. The results showed that N. oculata was able to remove up to 99.92 ± 0.04% of the copper content in the culture medium. A total of 89.29 ± 1.92% was eliminated through metabolism, and 10.70 ± 1.92% was removed by adsorption. These findings are favorable because they indicate that a large amount of copper was extracted due to the ability of the microalga to metabolize copper ions. The cell density, growth rate, and lipid content decreased with increased concentrations of copper in the culture medium. A positive effect on the fatty acid profile was found, as the saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) content improved when the copper concentration was higher than 0.1 mmol L −1 , which can potentiate the production of high-quality biodiesel. N. oculata is a good option for the treatment of acid mine drainage due to its ability to eliminate a substantial percentage of the copper present. Moreover, combining different culture systems such that heavy metals are removed to non-toxic levels in the first stage and high cell densities, which promote lipid production, is obtained in the second stage would be an advantageous strategy. Keywords Microalgae. Lipids. Biodiesel. Heavy metals. Acid mine drainage Highlights • Copper contents in acid mine drainage were removed by Nannochloropsis oculata. • Nannochloropsis oculata removed more copper through metabolism via than by adsorption. • Cell density, lipid content, and biomass productivity are reduced to high copper concentrations. • The saturated and mono-saturated fatty acid contents are increased to higher copper concentration.

Research paper thumbnail of Effect of the preparation method in the size of chitosan nanoparticles for the removal of allura red dye

Polymer Bulletin, 2018

Nanoparticles of chitosan-tripolyphosphate through two ionic gelation methods (Np1 and Np2) with ... more Nanoparticles of chitosan-tripolyphosphate through two ionic gelation methods (Np1 and Np2) with different dosages of TPP and stirring time were prepared and characterized (FTIR, TEM, SEM-EDS, AFM, XRD, DLS and BET) for the removal of an allura red dye. Np1 and Np2 were obtained with a diameter size of 315.5 nm and 437.4 nm, respectively, both with low polydispersity. The influence on smaller particle size was defined by a low concentration of chitosan solution (0.2 mg/mL) and a higher dosage of TPP (1 mg/mL), while the stirring time did not affect the particle size. Dye removal was placed in batch mode by varying adsorbent dosage, time and pH. The removal percentage (R%) in Np1 decreased with an increase in adsorbent dosage at pH 4 and 6, while Np2 remained constant at pH 2, 4 and 6. Adsorption essays in Np1 and Np2 revealed that under pH 2, an adsorbent dosage of 0.01 g and a contact time of 5 min, the adsorptions are complete. Np2 was recognized as the best adsorbent in comparison with Np1 due to the highest R% under several pHs. This research has demonstrated that the obtained nanoparticles by ionic gelation are suitable for removal of azo dyes in water.

Research paper thumbnail of Comparación De Métodos De Descarga Para Vertidos De Salmueras, Provenientes De Una Planta Desalinizadora en Sonora, México

Revista Internacional de Contaminación Ambiental, 2017

Palabras clave: ósmosis inversa, agua de rechazo, impacto ambiental RESUMEN Una alternativa para ... more Palabras clave: ósmosis inversa, agua de rechazo, impacto ambiental RESUMEN Una alternativa para hacer frente al desabasto de agua para consumo humano, industrial y agrícola, es la desalinización de aguas marinas y salobres. Este proceso consiste en la separación de sales del agua mediante diversas tecnologías. Sin embargo, a pesar de los beneficios que ofrecen, una desventaja importante del proceso es la cantidad de salmuera generada y su impacto ambiental como resultado de su alta salinidad. Bajo este contexto, el objetivo de este estudio es realizar una comparación de técnicas de descarga para vertidos de salmueras producidas por una planta desalinizadora. Se propuso llevar a cabo la investigación de métodos de disposición, para proponer la técnica más adecuada que disminuya el impacto ambiental producido en la zona de estudio. Para ello, se operó una planta desalinizadora de 100 m 3 /d con recuperación del 85 % en agua producto y 15 % en agua de rechazo. Se comparó la diferencia de concentraciones de salinidad entre agua alimentación y rechazo (salmuera). Los resultados indican que hubo un aumento en la salinidad del agua rechazo respecto a la de alimentación (de 2931 mg/L hasta 6756 mg/L de sólidos disueltos totales). Este aumento en la concentración muestra que es importante regular o disponer el vertido de salmueras para evitar impactos negativos al ecosistema receptor. Para este proyecto el método más adecuado, según la zona de estudio, es operar una granja acuícola para producción de camarón con alto valor comercial. Esta propuesta se identificó para el control y el uso de vertidos de salmuera en la zona del Valle del Yaqui,

Research paper thumbnail of Fouling Modeling and Optimization of Membrane Module Design for Brackish and Seawater Desalination in the Mexican Pacific Coast: Project Description and Progress

Membranes, 2016

Many regions of the world face significant water supply issues due to its scarcity. In the state ... more Many regions of the world face significant water supply issues due to its scarcity. In the state of Sonora, Mexico, there is physical scarcity of water, a grave problem that has generated social conflict in recent years. The Instituto Tecnologico de Sonora (ITSON) is making a significant bet on desalination technologies within its research and development projects and has incorporated the study and analysis of technical aspects of desalination in Chemical Engineering course programs, as well as in undergraduate, MSc, and PhD thesis topics. This work summarizes the Consejo Nacional de Ciencia y Tecnologia (CONACyT, Mexican National Science and Technology Council) Fellowship Research Project that is underway at ITSON, which aims to improve the understanding of reverse osmosis membrane biofouling with applications in desalination, specifically for Mexican Pacific coast seawater. As a preliminary study, an experimental system has been developed to test membranes and spacers, both commercial and produced in the laboratory through 3D printing techniques. The results indicate that variations in the design and dimensions of the spacers can lead to better productivity in terms of observed rejection and permeate flux. Therefore, it is necessary to test new spacer designs in order to optimize the results.

Research paper thumbnail of Synergies Between Pulsatile Flow and Spacer Filaments in Reverse Osmosis Modules

Membranes, 2016

This work uses 2D fluid dynamics and mass transfer simulations to evaluate the use of pulsatile f... more This work uses 2D fluid dynamics and mass transfer simulations to evaluate the use of pulsatile flow in spiral wound reverse osmosis modules. The aim of pulsatile flow is to enhance mass transfer and increase the performance of the membrane modules, without significantly affecting pressure drop and energy losses. The synergies that exist between pulsatile flow and spacer filament-induced oscillations are explored. The results indicate that there is an optimal frequency that amplifies the perturbations. Flow pulsations at the optimal frequency (which is related to the natural oscillating frequency of the channel) cause vortex shedding at Reynolds numbers below 350, compared to values above 500 that would be necessary without pulsatile flow. This leads to an increase in mass transfer and permeate flux of the order of 12 % at those conditions.

Research paper thumbnail of Biofouling Studies on Thin Film Composite Membranes for Reverse Osmosis Desalination Processes

Membranes, 2016

Membranes are the most sensitive unit to the damaging effect of biofouling in reverse osmosis equ... more Membranes are the most sensitive unit to the damaging effect of biofouling in reverse osmosis equipment. Biofouling is defined by many variables and elements, including a surface-deposited organized microbial ecosystem showing complex functional and structural characteristics, known as biofilm. Biofilm formation results from the excretion of an extracellular protective matrix by microorganisms. Biofilm blocks reverse osmosis (RO) membranes, decreasing the permeability and, consequently, the rate at which water can be desalinated. The nutritional and microbial parameters of water samples from the Cortes Sea, and specifically from the coast of Guaymas, Sonora, Mexico, were determined. The water samples were used to isolate marine microorganism present in this ecosystem. A modified growth medium was developed to represent this specific sea environment. Finally, several artificial biofouling-related experiments were carried out in order to reproduce, and then, analyze the potential membrane damage caused by biofouling. A discrepancy was found between the salinity in the water samples from the Guaymas coast and the standard salinity expected for the Pacific Ocean. Several causes for this variability and its effect on the physical and chemical parameters are proposed, and the potential impact on desalination plants due to the microbial population, which will ultimately be responsible for biofouling on RO membranes, is analyzed.

Research paper thumbnail of Membrane module autopsy used in the reverse osmosis process

Journal of Enviromental Sciences and Natural Resources, 2020

This research was done to get acquainted with the characteristic of the membrane module in spiral... more This research was done to get acquainted with the characteristic of the membrane module in spiral, used in the osmosis reverse process. The goal to know its measure, components, hydrophilic, topography, materials and performance. The membranes of the module were characterized by the next techniques: atomic force microscopy (AFM), infrared spectroscopy by ATR (Attenuated Total Reflectance), contact angle and cross- flow equipment. Agree with the autopsy, the infrared spectrums indicate that the membrane is constituted by support of polyester paper, a polysulfone layer, a cellulose acetate layer and polyamide layer. The feed spacer is polypropylene and the permeate spacer is polyethylene terephthalate. All the measures did the membrane module were the same as the technical sheet from the manufacturer. The contact angle was 22.4±3.55° and roughness of 182.43±42 nm. The performance of the membrane was 70% to reject salts of feed 1000 ppm Na2SO4.

Research paper thumbnail of The Use of the RAFT‐Technique for the Preparation of Temperature/pH Sensitive Polymers in Different Architectures

Macromolecular Symposia

In this contribution we report the use of the RAFT-technique for the preparation of three types o... more In this contribution we report the use of the RAFT-technique for the preparation of three types of responsive polymeric materials with a high potential of application in the biomedical field: 1.-Diblock copolymers with reversible self-assembly capacity as a function of pH based on N,N′-diethylaminoethyl methacrylate (DEAEM) and 2-methacryloyloxy benzoic acid (MAOB); 2.-Diblock copolymers with reversible self-assembly capacity as a function of temperature, based N-isopropylacrylamide (NIPAAm) and n-hexyl acrylate (HA); and 3.-Polymeric stars with random number of arms consisting either in NIPAAm-arms or copolymeric NIPAAm-arms and hydrophobic core.

Research paper thumbnail of Macromol. Symp. 283-284

Macromolecular Symposia, 2009

Cover: The inaugural US-Mexico Symposium on Advances in Polymer Science, MACROMEX 2008, took plac... more Cover: The inaugural US-Mexico Symposium on Advances in Polymer Science, MACROMEX 2008, took place in Los Cabos, Mexico. This first bi-national conference was the result of a joint effort of the Mexican Polymer Society and the Polymer Chemistry Division of the American ...

Research paper thumbnail of Modification of Thin Film Composite Membrane by Chitosan–Silver Particles to Improve Desalination and Anti-Biofouling Performance

Membranes

Reverse osmosis (RO) desalination is a technology that is commonly used to mitigate water scarcit... more Reverse osmosis (RO) desalination is a technology that is commonly used to mitigate water scarcity problems; one of its disadvantages is the bio-fouling of the membranes used, which reduces its performance. In order to minimize this problem, this study prepared modified thin film composite (TFC) membranes by the incorporation of chitosan–silver particles (CS–Ag) of different molecular weights, and evaluated them in terms of their anti-biofouling and desalination performances. The CS–Ag were obtained using ionotropic gelation, and were characterized by Fourier transform infrared spectroscopy (FTIR), high-resolution scanning electron microscopy (HR-SEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA) and dynamic light scattering (DLS). The modified membranes were synthetized by the incorporation of the CS–Ag using the interfacial polymerization method. The membranes (MCS–Ag) were characterized by Fourier transform infrared spectroscopy (FTIR), atomic forc...

Research paper thumbnail of NANOFILTRATION MEMBRANES, PREPARED VIA INTERFACIALPOLYMERIZATION, DOPED WITH ZnO NANOPARTICLES: EFFECT ONPERFORMANCE

Revista Mexicana de Ingeniería Química

Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo int... more Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo intemperizados en suelos y sedimentos (Biodegradation modeling of sludge bioreactors of total petroleum hydrocarbons weathering in soil and sediments)

Research paper thumbnail of Modification and characterization of TFC membranes with Ag nanoparticles: application in seawater desalination

Research paper thumbnail of Effect of Temperature on Diluate Water in Batch Electrodialysis Reversal

Separations, 2021

A high percentage of the agricultural wells in the state of Sonora are overexploited, thus genera... more A high percentage of the agricultural wells in the state of Sonora are overexploited, thus generating a significant degree of saline intrusion and abandonment by nearby communities. In this paper, the effect of temperature on the final concentration of diluted water was evaluated with variations in voltage and input concentration in a batch electrodialysis reversal (EDR) process in order to find the optimal operating conditions, with an emphasis on reducing the energy consumption and cost of desalinated water. Thirty-six samples were prepared: eighteen samples of 2000 mg/L total dissolved solids (TDS) and eighteen samples of 5000 mg/L TDS; brackish well water of 639 mg/L TDS and synthetic salt were mixed to obtain these concentrations. Three different temperatures (25, 30, and 35 °C) and two different voltages (10 and 20 V) were tested for each sample after evaluating the limiting current density. The best salt removal occurred in the 20 V sets, with 18.34% higher removal for the 20...

Research paper thumbnail of Using Desalination to Improve Agricultural Yields: Success Cases in Mexico

Desalination and Water Treatment, 2018

Water scarcity is a global problem, motivating growth and development of new technologies for wat... more Water scarcity is a global problem, motivating growth and development of new technologies for water treatment, reuse and desalination. For many arid regions in Mexico, especially in the northwest, agriculture is an important economic activity. The Yaqui Valley in Sonora, Mexico, faces problems related to aquifer overexploitation and saline intrusion, which have increased salt concentration in well water to 2000-9000 mg/L total dissolved solids (TDS) and led to soil salinization and low crop yields. This work evaluates the effect of TDS in irrigation water on crop yield. A 150 m 3 /d desalination plant was used, consisting of 12 SWC4B-MAX membrane modules, with 98% rejection and 75% recovery. Two crops were irrigated with control (4000 mg/L) and desalinated water (200 mg/L). Sorghum (Sorghum) had yields of 7.9 and 8.8 ton/ha, whereas tomatillo (Physalis philadelphica) had yields of 30.82 and 35.88 ton/ha, respectively. Evidently, the desalination process influences agricultural yields.

Research paper thumbnail of Desalación por ósmosis inversa y su aprovechamiento en agricultura en el valle del Yaqui, Sonora, México

Tecnologia y Ciencias del Agua, 2016

Sonora, situado al noroeste de Mexico, ocupa el segundo lugar en cultivos de riego en el pais. Lo... more Sonora, situado al noroeste de Mexico, ocupa el segundo lugar en cultivos de riego en el pais. Los problemas de disponibilidad de los recursos hidricos, principalmente para agricultura en ese estado, se deben a la alta concentracion de sales en los pozos, que van desde 2 000 hasta 5000 mg/l de solidos disueltos totales (SDT). Estos altos valores de SDT son atribuidos a efectos de intrusion salina (Devora, Gonzalez, & Saldivar, 2009), al tener una excesiva explotacion del manto acuifero (Conagua, 2011). Sin embargo, el uso de tecnologias de desalacion y modelos de prediccion del proceso permiten aprovechar el recurso de manera optima tanto en agua producto como en el rechazo. Es por esto que el objetivo es definir un modelo matematico de simulacion para la prediccion de la operacion de una planta desaladora de osmosis inversa alimentada por agua salobre, validando que el agua producto cumpla con los limites permisibles para su uso en agricultura. Con motivo de validar el modelo, el e...

Research paper thumbnail of Sistema De Adquisición De Datos De Bajo Costo Para Un Invernadero Basado en Tecnología De Acceso Libre

Resumen En este trabajo se presenta un sistema de adquisicion de datos desarrollado para un inver... more Resumen En este trabajo se presenta un sistema de adquisicion de datos desarrollado para un invernadero clasico cenital que se basa en el microcontrolador ESP826612E y la computadora de bolsillo Raspberry Pi 3, los cuales son plataformas de hardware libre. Los parametros obtenidos son la temperatura y la humedad. En el metodo se incluye la integracion de los componentes al sistema de adquisicion de datos, en particular el sensor de temperatura y humedad (DHT11), el servidor (Mosquitto y Node-RED), utilizando los protocolos de comunicacion inalambrica (WiFi y MQTT). Los resultados muestran la factibilidad para utilizar un conjunto de dispositivos inalambricos para la integracion de un sistema donde se requiere procesar informacion de manera remota, en este caso un invernadero. Palabras Claves: Adquisicion de datos, invernadero, mosquitto, Node-RED, Raspberry Pi. LOW COST DATA ACQUISITION SYSTEM FOR A GREENHOUSE BASED ON FREE ACCESS TECHNOLOGY Abstract A data acquisition system for a ...

Research paper thumbnail of Influence of different reactor types on Nannochloropsis oculata microalgae culture for lipids and fatty acid production

Journal of the American Oil Chemists' Society, 2021

Research paper thumbnail of Effect of seawater variability on endemic bacterial biofouling of a reverse osmosis membrane coated with iron nanoparticles (FeNPs)

Chemical Engineering Science, 2020

Biofouling study of endemic bacteria on iron nanoparticle coated membrane. The Sea of Cortez wate... more Biofouling study of endemic bacteria on iron nanoparticle coated membrane. The Sea of Cortez water has a high potential to biofoul the Reverse Osmosis membranes. Physicochemical parameters values of El Sol Beach water delay biofilm growth. Temperature, pH and dissolved oxygen affect directly the biofilm growth. Temperature, pH and dissolved oxygen improve iron nanoparticle coating effectiveness.

Research paper thumbnail of Uptake of copper from acid mine drainage by the microalgae Nannochloropsis oculata

Environmental Science and Pollution Research, 2019

The removal of heavy metals from acid mine drainage is a key factor for avoiding damage to the en... more The removal of heavy metals from acid mine drainage is a key factor for avoiding damage to the environment. The microalga Nannochloropsis oculata was cultured in an algal medium with 0.05, 0.1, 0.15, 0.2, and 0.25 mM copper under completely defined conditions to assess its removal capacity; the effects of copper on the cell density and lipid productivity of N. oculata were also evaluated. The results showed that N. oculata was able to remove up to 99.92 ± 0.04% of the copper content in the culture medium. A total of 89.29 ± 1.92% was eliminated through metabolism, and 10.70 ± 1.92% was removed by adsorption. These findings are favorable because they indicate that a large amount of copper was extracted due to the ability of the microalga to metabolize copper ions. The cell density, growth rate, and lipid content decreased with increased concentrations of copper in the culture medium. A positive effect on the fatty acid profile was found, as the saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) content improved when the copper concentration was higher than 0.1 mmol L −1 , which can potentiate the production of high-quality biodiesel. N. oculata is a good option for the treatment of acid mine drainage due to its ability to eliminate a substantial percentage of the copper present. Moreover, combining different culture systems such that heavy metals are removed to non-toxic levels in the first stage and high cell densities, which promote lipid production, is obtained in the second stage would be an advantageous strategy. Keywords Microalgae. Lipids. Biodiesel. Heavy metals. Acid mine drainage Highlights • Copper contents in acid mine drainage were removed by Nannochloropsis oculata. • Nannochloropsis oculata removed more copper through metabolism via than by adsorption. • Cell density, lipid content, and biomass productivity are reduced to high copper concentrations. • The saturated and mono-saturated fatty acid contents are increased to higher copper concentration.

Research paper thumbnail of Effect of the preparation method in the size of chitosan nanoparticles for the removal of allura red dye

Polymer Bulletin, 2018

Nanoparticles of chitosan-tripolyphosphate through two ionic gelation methods (Np1 and Np2) with ... more Nanoparticles of chitosan-tripolyphosphate through two ionic gelation methods (Np1 and Np2) with different dosages of TPP and stirring time were prepared and characterized (FTIR, TEM, SEM-EDS, AFM, XRD, DLS and BET) for the removal of an allura red dye. Np1 and Np2 were obtained with a diameter size of 315.5 nm and 437.4 nm, respectively, both with low polydispersity. The influence on smaller particle size was defined by a low concentration of chitosan solution (0.2 mg/mL) and a higher dosage of TPP (1 mg/mL), while the stirring time did not affect the particle size. Dye removal was placed in batch mode by varying adsorbent dosage, time and pH. The removal percentage (R%) in Np1 decreased with an increase in adsorbent dosage at pH 4 and 6, while Np2 remained constant at pH 2, 4 and 6. Adsorption essays in Np1 and Np2 revealed that under pH 2, an adsorbent dosage of 0.01 g and a contact time of 5 min, the adsorptions are complete. Np2 was recognized as the best adsorbent in comparison with Np1 due to the highest R% under several pHs. This research has demonstrated that the obtained nanoparticles by ionic gelation are suitable for removal of azo dyes in water.

Research paper thumbnail of Comparación De Métodos De Descarga Para Vertidos De Salmueras, Provenientes De Una Planta Desalinizadora en Sonora, México

Revista Internacional de Contaminación Ambiental, 2017

Palabras clave: ósmosis inversa, agua de rechazo, impacto ambiental RESUMEN Una alternativa para ... more Palabras clave: ósmosis inversa, agua de rechazo, impacto ambiental RESUMEN Una alternativa para hacer frente al desabasto de agua para consumo humano, industrial y agrícola, es la desalinización de aguas marinas y salobres. Este proceso consiste en la separación de sales del agua mediante diversas tecnologías. Sin embargo, a pesar de los beneficios que ofrecen, una desventaja importante del proceso es la cantidad de salmuera generada y su impacto ambiental como resultado de su alta salinidad. Bajo este contexto, el objetivo de este estudio es realizar una comparación de técnicas de descarga para vertidos de salmueras producidas por una planta desalinizadora. Se propuso llevar a cabo la investigación de métodos de disposición, para proponer la técnica más adecuada que disminuya el impacto ambiental producido en la zona de estudio. Para ello, se operó una planta desalinizadora de 100 m 3 /d con recuperación del 85 % en agua producto y 15 % en agua de rechazo. Se comparó la diferencia de concentraciones de salinidad entre agua alimentación y rechazo (salmuera). Los resultados indican que hubo un aumento en la salinidad del agua rechazo respecto a la de alimentación (de 2931 mg/L hasta 6756 mg/L de sólidos disueltos totales). Este aumento en la concentración muestra que es importante regular o disponer el vertido de salmueras para evitar impactos negativos al ecosistema receptor. Para este proyecto el método más adecuado, según la zona de estudio, es operar una granja acuícola para producción de camarón con alto valor comercial. Esta propuesta se identificó para el control y el uso de vertidos de salmuera en la zona del Valle del Yaqui,

Research paper thumbnail of Fouling Modeling and Optimization of Membrane Module Design for Brackish and Seawater Desalination in the Mexican Pacific Coast: Project Description and Progress

Membranes, 2016

Many regions of the world face significant water supply issues due to its scarcity. In the state ... more Many regions of the world face significant water supply issues due to its scarcity. In the state of Sonora, Mexico, there is physical scarcity of water, a grave problem that has generated social conflict in recent years. The Instituto Tecnologico de Sonora (ITSON) is making a significant bet on desalination technologies within its research and development projects and has incorporated the study and analysis of technical aspects of desalination in Chemical Engineering course programs, as well as in undergraduate, MSc, and PhD thesis topics. This work summarizes the Consejo Nacional de Ciencia y Tecnologia (CONACyT, Mexican National Science and Technology Council) Fellowship Research Project that is underway at ITSON, which aims to improve the understanding of reverse osmosis membrane biofouling with applications in desalination, specifically for Mexican Pacific coast seawater. As a preliminary study, an experimental system has been developed to test membranes and spacers, both commercial and produced in the laboratory through 3D printing techniques. The results indicate that variations in the design and dimensions of the spacers can lead to better productivity in terms of observed rejection and permeate flux. Therefore, it is necessary to test new spacer designs in order to optimize the results.

Research paper thumbnail of Synergies Between Pulsatile Flow and Spacer Filaments in Reverse Osmosis Modules

Membranes, 2016

This work uses 2D fluid dynamics and mass transfer simulations to evaluate the use of pulsatile f... more This work uses 2D fluid dynamics and mass transfer simulations to evaluate the use of pulsatile flow in spiral wound reverse osmosis modules. The aim of pulsatile flow is to enhance mass transfer and increase the performance of the membrane modules, without significantly affecting pressure drop and energy losses. The synergies that exist between pulsatile flow and spacer filament-induced oscillations are explored. The results indicate that there is an optimal frequency that amplifies the perturbations. Flow pulsations at the optimal frequency (which is related to the natural oscillating frequency of the channel) cause vortex shedding at Reynolds numbers below 350, compared to values above 500 that would be necessary without pulsatile flow. This leads to an increase in mass transfer and permeate flux of the order of 12 % at those conditions.

Research paper thumbnail of Biofouling Studies on Thin Film Composite Membranes for Reverse Osmosis Desalination Processes

Membranes, 2016

Membranes are the most sensitive unit to the damaging effect of biofouling in reverse osmosis equ... more Membranes are the most sensitive unit to the damaging effect of biofouling in reverse osmosis equipment. Biofouling is defined by many variables and elements, including a surface-deposited organized microbial ecosystem showing complex functional and structural characteristics, known as biofilm. Biofilm formation results from the excretion of an extracellular protective matrix by microorganisms. Biofilm blocks reverse osmosis (RO) membranes, decreasing the permeability and, consequently, the rate at which water can be desalinated. The nutritional and microbial parameters of water samples from the Cortes Sea, and specifically from the coast of Guaymas, Sonora, Mexico, were determined. The water samples were used to isolate marine microorganism present in this ecosystem. A modified growth medium was developed to represent this specific sea environment. Finally, several artificial biofouling-related experiments were carried out in order to reproduce, and then, analyze the potential membrane damage caused by biofouling. A discrepancy was found between the salinity in the water samples from the Guaymas coast and the standard salinity expected for the Pacific Ocean. Several causes for this variability and its effect on the physical and chemical parameters are proposed, and the potential impact on desalination plants due to the microbial population, which will ultimately be responsible for biofouling on RO membranes, is analyzed.

Research paper thumbnail of Membrane module autopsy used in the reverse osmosis process

Journal of Enviromental Sciences and Natural Resources, 2020

This research was done to get acquainted with the characteristic of the membrane module in spiral... more This research was done to get acquainted with the characteristic of the membrane module in spiral, used in the osmosis reverse process. The goal to know its measure, components, hydrophilic, topography, materials and performance. The membranes of the module were characterized by the next techniques: atomic force microscopy (AFM), infrared spectroscopy by ATR (Attenuated Total Reflectance), contact angle and cross- flow equipment. Agree with the autopsy, the infrared spectrums indicate that the membrane is constituted by support of polyester paper, a polysulfone layer, a cellulose acetate layer and polyamide layer. The feed spacer is polypropylene and the permeate spacer is polyethylene terephthalate. All the measures did the membrane module were the same as the technical sheet from the manufacturer. The contact angle was 22.4±3.55° and roughness of 182.43±42 nm. The performance of the membrane was 70% to reject salts of feed 1000 ppm Na2SO4.

Research paper thumbnail of The Use of the RAFT‐Technique for the Preparation of Temperature/pH Sensitive Polymers in Different Architectures

Macromolecular Symposia

In this contribution we report the use of the RAFT-technique for the preparation of three types o... more In this contribution we report the use of the RAFT-technique for the preparation of three types of responsive polymeric materials with a high potential of application in the biomedical field: 1.-Diblock copolymers with reversible self-assembly capacity as a function of pH based on N,N′-diethylaminoethyl methacrylate (DEAEM) and 2-methacryloyloxy benzoic acid (MAOB); 2.-Diblock copolymers with reversible self-assembly capacity as a function of temperature, based N-isopropylacrylamide (NIPAAm) and n-hexyl acrylate (HA); and 3.-Polymeric stars with random number of arms consisting either in NIPAAm-arms or copolymeric NIPAAm-arms and hydrophobic core.