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Efrem Curcio - One of the best experts on this subject based on the ideXlab platform.
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salinity gradient power reverse electrodialysis cation exchange Membrane design based on polypyrrole chitosan composites for enhanced monovalent selectivity
Chemical Engineering Journal, 2020Co-Authors: Ramato Ashu Tufa, Jaromír Hnát, Debabrata Chanda, Enrica Fontananova, Efrem Curcio, Gianluca Di Profio, Theo Piallat, Martin Paidar, Karel BouzekAbstract:Abstract Reverse electrodialysis (RED) is one of the most promising Membrane-based processes for renewable energy generation from mixing two solutions of different salinity. However, the presence of Mg2+ in natural water has been shown to drastically reduce open circuit voltage (OCV) and output power of RED. To alleviate this challenge, commercial cation exchange Membranes (CEM) supplied by Fujifilm Manufacturing Europe B.V. (The Netherlands) were chemically modified by polypyrrole (PPy)/chitosan (CS) composites under controlled Pyrrole (Py) concentration (0.025–1 M) and polymerization time (0–8 h). The modified Membranes were physically characterized by FTIR, SEM and EDX along with the determination of key electrochemical properties like ion exchange capacity, ionic conductivity, monovalent selectivity and swelling degree. The monovalent selectivity (Na+ vs Mg2+) of the modified Membranes, evaluated based on flux of ions by diffusion dialysis, indicated up to 3-fold improvement compared to pristine Membranes inline with the enhanced OCV (up to 20%) during RED test in multi-ion solution. This was obtained without significant change in Membrane and interface resistances as depicted by electrochemical impedance spectroscopy. The modified Membranes displayed power densities in the range of 0.6–1.5 W/m2MP (MP: Membrane Pair) with more than 42% improvement compared to pristine Membranes during RED test with multi-ion solutions. Although there is a gap for further improvement, these findings highlight a promising use of conducting polymers to design a highly selective and conductive Membrane for RED.
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effect of mg2 ions on energy generation by reverse electrodialysis
Journal of Membrane Science, 2016Co-Authors: Ahmet H Avci, Pinkey Sarkar, Diego Messana, Pietro Argurio, Ramato Ashu Tufa, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract Reverse Electrodialysis is today recognized as one of the most promising technology to harvest Salinity Gradient Power (SGP-RE). However, the effectiveness of SGP-RE in real practice is still not clearly defined due to the lack of specific studies in literature, being in large part limited to investigations on pure NaCl solutions. In this work we experimentally investigated the effect of Mg2+, the most abundant cation in natural water after Na+, on SGP-RE performance by power measurements on a lab-scale stack prototype. Maximum power density ranged from 1.06 W/m2MP (MP: Membrane Pair) - generated when feeding SGP-RE prototype with 0.5 molal//4 molal NaCl, to 0.06 W/m2MP - measured when using 0.5 molal//4 molal MgCl2 solutions. Likewise, open circuit voltage decreased from 1.70 to 0.72 V. Evidence of uphill transport in the range of 0–30% MgCl2 was confirmed by Ion Chromatography analysis carried out on inlet and outlet streams of SGP-RE stack. Electrochemical Impedance Spectroscopy analysis revealed that cation exchange Membrane resistance was critically affected by Mg2+ concentration: Membrane resistance, from a value of 2.41 Ω cm2 in pure NaCl solution, increased tenfold in pure MgCl2 solution.
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Membrane distillation and reverse electrodialysis for near zero liquid discharge and low energy seawater desalination
Journal of Membrane Science, 2015Co-Authors: Ramato Ashu Tufa, E Brauns, Willem Van Baak, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract With a total capacity of 70 million cubic meters per day, seawater desalination industry represents the most affordable source of drinking water for many people living in arid areas of the world. Seawater Reverse Osmosis (SWRO) technology, driven by the impressive development in Membrane materials, modules and process design, currently shows an overall energy consumption of 3–4 kW h per m 3 of desalted water, substantially lower than thermal systems; however, the theoretical energy demand to produce 1 m 3 of potable water from 2 m 3 of seawater (50% recovery factor) is 1.1 kW h. In order to move towards this goal, the possibility to recover the energy content of discharged concentrates assumes a strategic relevance. In this work, an innovative approach combining Direct Contact Membrane Distillation (DCMD) and Reverse Electrodialysis (RE) is tested for simultaneous water and energy production from SWRO brine, thus implementing the concept of low energy and Near-Zero Liquid Discharge in seawater desalination. DCMD operated on 1 M NaCl RO retentate fed at 40–50 °C resulted in a Volume Reduction Factor (VRF) up to 83.6% with transMembrane flux in the range of 1.2–2.4 kg/m 2 h. The performance of RE stack fed with DCMD brine (4–5.4 M) and seawater (0.5 M) was investigated at different temperatures (10–45 °C) and flow velocities (0.7–1.1 cm/s). Experimental data show the possibility to obtain an Open Circuit Voltage (OCV) in the range of 1.5–2.3 V and a gross power density of 0.9–2.4 W / m MP 2 (Membrane Pair). In general, optimization is required to find best operating conditions for the proposed system.
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Membrane distillation and reverse electrodialysis for near zero liquid discharge and low energy seawater desalination
Journal of Membrane Science, 2015Co-Authors: Ramato Ashu Tufa, E Brauns, Willem Van Baak, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract With a total capacity of 70 million cubic meters per day, seawater desalination industry represents the most affordable source of drinking water for many people living in arid areas of the world. Seawater Reverse Osmosis (SWRO) technology, driven by the impressive development in Membrane materials, modules and process design, currently shows an overall energy consumption of 3–4 kW h per m 3 of desalted water, substantially lower than thermal systems; however, the theoretical energy demand to produce 1 m 3 of potable water from 2 m 3 of seawater (50% recovery factor) is 1.1 kW h. In order to move towards this goal, the possibility to recover the energy content of discharged concentrates assumes a strategic relevance. In this work, an innovative approach combining Direct Contact Membrane Distillation (DCMD) and Reverse Electrodialysis (RE) is tested for simultaneous water and energy production from SWRO brine, thus implementing the concept of low energy and Near-Zero Liquid Discharge in seawater desalination. DCMD operated on 1 M NaCl RO retentate fed at 40–50 °C resulted in a Volume Reduction Factor (VRF) up to 83.6% with transMembrane flux in the range of 1.2–2.4 kg/m 2 h. The performance of RE stack fed with DCMD brine (4–5.4 M) and seawater (0.5 M) was investigated at different temperatures (10–45 °C) and flow velocities (0.7–1.1 cm/s). Experimental data show the possibility to obtain an Open Circuit Voltage (OCV) in the range of 1.5–2.3 V and a gross power density of 0.9–2.4 W / m MP 2 (Membrane Pair). In general, optimization is required to find best operating conditions for the proposed system.
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potential of brackish water and brine for energy generation by salinity gradient power reverse electrodialysis sgp re
RSC Advances, 2014Co-Authors: Ramato Ashu Tufa, Simon Grasman, J Veerman, Willem Van Baak, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:In the present work, a salinity gradient power-reverse electrodialysis (SGP-RE) unit was tested for the production of electrical energy by exploiting the chemical potential of real brackish water and exhaust brine from a solar pond. A cross-flow SGP-RE module (REDstack B.V.), equipped with AEM-80045 and CEM-80050 Membranes specifically developed by Fujifilm Manufacturing Europe B.V. within the EU-funded project REAPOWER (“Reverse Electrodialysis Alternative Power Production”), was able to generate a maximum power density (expressed in W m−2 Membrane Pair – MP) of 3.04 W m−2 MP when operated with pure NaCl aqueous solutions (0.1 M in low concentration compartment – LCC, 5 M in high concentration compartment – HCC) at 20 °C and at a recirculation rate of 20 L h−1. However, a drastic reduction to 1.13 W m−2 (−63%) was observed when feeding the SGP-RE unit with artificial multi-ion solutions mimicking real brackish water and exhaust brine. Further experimental activity allowed to identify Mg2+ ion as responsible for the significant increase in stack resistance and consequent depletion in SGP-RE performance. Therefore, specific softening treatments of the real solutions should be considered in order to maintain the process efficiency at practical level.
Gianluca Di Profio - One of the best experts on this subject based on the ideXlab platform.
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salinity gradient power reverse electrodialysis cation exchange Membrane design based on polypyrrole chitosan composites for enhanced monovalent selectivity
Chemical Engineering Journal, 2020Co-Authors: Ramato Ashu Tufa, Jaromír Hnát, Debabrata Chanda, Enrica Fontananova, Efrem Curcio, Gianluca Di Profio, Theo Piallat, Martin Paidar, Karel BouzekAbstract:Abstract Reverse electrodialysis (RED) is one of the most promising Membrane-based processes for renewable energy generation from mixing two solutions of different salinity. However, the presence of Mg2+ in natural water has been shown to drastically reduce open circuit voltage (OCV) and output power of RED. To alleviate this challenge, commercial cation exchange Membranes (CEM) supplied by Fujifilm Manufacturing Europe B.V. (The Netherlands) were chemically modified by polypyrrole (PPy)/chitosan (CS) composites under controlled Pyrrole (Py) concentration (0.025–1 M) and polymerization time (0–8 h). The modified Membranes were physically characterized by FTIR, SEM and EDX along with the determination of key electrochemical properties like ion exchange capacity, ionic conductivity, monovalent selectivity and swelling degree. The monovalent selectivity (Na+ vs Mg2+) of the modified Membranes, evaluated based on flux of ions by diffusion dialysis, indicated up to 3-fold improvement compared to pristine Membranes inline with the enhanced OCV (up to 20%) during RED test in multi-ion solution. This was obtained without significant change in Membrane and interface resistances as depicted by electrochemical impedance spectroscopy. The modified Membranes displayed power densities in the range of 0.6–1.5 W/m2MP (MP: Membrane Pair) with more than 42% improvement compared to pristine Membranes during RED test with multi-ion solutions. Although there is a gap for further improvement, these findings highlight a promising use of conducting polymers to design a highly selective and conductive Membrane for RED.
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effect of mg2 ions on energy generation by reverse electrodialysis
Journal of Membrane Science, 2016Co-Authors: Ahmet H Avci, Pinkey Sarkar, Diego Messana, Pietro Argurio, Ramato Ashu Tufa, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract Reverse Electrodialysis is today recognized as one of the most promising technology to harvest Salinity Gradient Power (SGP-RE). However, the effectiveness of SGP-RE in real practice is still not clearly defined due to the lack of specific studies in literature, being in large part limited to investigations on pure NaCl solutions. In this work we experimentally investigated the effect of Mg2+, the most abundant cation in natural water after Na+, on SGP-RE performance by power measurements on a lab-scale stack prototype. Maximum power density ranged from 1.06 W/m2MP (MP: Membrane Pair) - generated when feeding SGP-RE prototype with 0.5 molal//4 molal NaCl, to 0.06 W/m2MP - measured when using 0.5 molal//4 molal MgCl2 solutions. Likewise, open circuit voltage decreased from 1.70 to 0.72 V. Evidence of uphill transport in the range of 0–30% MgCl2 was confirmed by Ion Chromatography analysis carried out on inlet and outlet streams of SGP-RE stack. Electrochemical Impedance Spectroscopy analysis revealed that cation exchange Membrane resistance was critically affected by Mg2+ concentration: Membrane resistance, from a value of 2.41 Ω cm2 in pure NaCl solution, increased tenfold in pure MgCl2 solution.
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Salinity gradient power-reverse electrodialysis and alkaline polymer electrolyte water electrolysis for hydrogen production
Journal of Membrane Science, 2016Co-Authors: Ramato Ashu Tufa, Jaromír Hnát, Debabrata Chanda, Elisabetta Rugiero, J Veerman, Willem Van Baak, Enrica Fontananova, Gianluca Di Profio, Enrico Drioli, Karel BouzekAbstract:Abstract In this work, innovative use of Salinity Gradient Power (SGP) as renewable energy source for indirect production of hydrogen is addressed. A lab-scale reverse electrodialysis (RED) unit, fed with different NaCl solutions mimicking highly concentrated brine (5 M), Reverse Osmosis retentate (1 M), seawater (0.5 M) and brackish water (0.1 M), was coupled to an alkaline polymer electrolyte (APE) water electrolysis cell. SGP-RED unit, equipped with 27 cell-Pairs, reached at best an Open Circuit Voltage (OCV) of 3.7 V and maximum gross power density of 3.2 W m −2 MP (Membrane Pair) when feeding the low concentration compartment (LCC) with 0.1 M NaCl and the High Concentration Compartment (HCC) with 5 M NaCl. The single-cell APE water electrolysis unit, operated at 1.8 V, attained a current density of 120 mA cm −2 under the following configuration: 10% w/w KOH electrolyte, highly conductive anion selective Membrane composed of inert low-density polyethylene, finely milled anion selective particles and water-soluble poly (ethylene glycol-ran-propylene glycol), non-Platinum catalysts (NiCo 2 O 4 and NiFe 2 O 4 ) loading of 10 mg cm −2 and 15%w/w polymer binder at both cathode and anode, and operational temperature of 65 °C. The integrated system resulted in a maximum hydrogen production rate of 44 cm 3 h −1 per cm 2 of electrode surface area.
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Membrane distillation and reverse electrodialysis for near zero liquid discharge and low energy seawater desalination
Journal of Membrane Science, 2015Co-Authors: Ramato Ashu Tufa, E Brauns, Willem Van Baak, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract With a total capacity of 70 million cubic meters per day, seawater desalination industry represents the most affordable source of drinking water for many people living in arid areas of the world. Seawater Reverse Osmosis (SWRO) technology, driven by the impressive development in Membrane materials, modules and process design, currently shows an overall energy consumption of 3–4 kW h per m 3 of desalted water, substantially lower than thermal systems; however, the theoretical energy demand to produce 1 m 3 of potable water from 2 m 3 of seawater (50% recovery factor) is 1.1 kW h. In order to move towards this goal, the possibility to recover the energy content of discharged concentrates assumes a strategic relevance. In this work, an innovative approach combining Direct Contact Membrane Distillation (DCMD) and Reverse Electrodialysis (RE) is tested for simultaneous water and energy production from SWRO brine, thus implementing the concept of low energy and Near-Zero Liquid Discharge in seawater desalination. DCMD operated on 1 M NaCl RO retentate fed at 40–50 °C resulted in a Volume Reduction Factor (VRF) up to 83.6% with transMembrane flux in the range of 1.2–2.4 kg/m 2 h. The performance of RE stack fed with DCMD brine (4–5.4 M) and seawater (0.5 M) was investigated at different temperatures (10–45 °C) and flow velocities (0.7–1.1 cm/s). Experimental data show the possibility to obtain an Open Circuit Voltage (OCV) in the range of 1.5–2.3 V and a gross power density of 0.9–2.4 W / m MP 2 (Membrane Pair). In general, optimization is required to find best operating conditions for the proposed system.
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Membrane distillation and reverse electrodialysis for near zero liquid discharge and low energy seawater desalination
Journal of Membrane Science, 2015Co-Authors: Ramato Ashu Tufa, E Brauns, Willem Van Baak, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract With a total capacity of 70 million cubic meters per day, seawater desalination industry represents the most affordable source of drinking water for many people living in arid areas of the world. Seawater Reverse Osmosis (SWRO) technology, driven by the impressive development in Membrane materials, modules and process design, currently shows an overall energy consumption of 3–4 kW h per m 3 of desalted water, substantially lower than thermal systems; however, the theoretical energy demand to produce 1 m 3 of potable water from 2 m 3 of seawater (50% recovery factor) is 1.1 kW h. In order to move towards this goal, the possibility to recover the energy content of discharged concentrates assumes a strategic relevance. In this work, an innovative approach combining Direct Contact Membrane Distillation (DCMD) and Reverse Electrodialysis (RE) is tested for simultaneous water and energy production from SWRO brine, thus implementing the concept of low energy and Near-Zero Liquid Discharge in seawater desalination. DCMD operated on 1 M NaCl RO retentate fed at 40–50 °C resulted in a Volume Reduction Factor (VRF) up to 83.6% with transMembrane flux in the range of 1.2–2.4 kg/m 2 h. The performance of RE stack fed with DCMD brine (4–5.4 M) and seawater (0.5 M) was investigated at different temperatures (10–45 °C) and flow velocities (0.7–1.1 cm/s). Experimental data show the possibility to obtain an Open Circuit Voltage (OCV) in the range of 1.5–2.3 V and a gross power density of 0.9–2.4 W / m MP 2 (Membrane Pair). In general, optimization is required to find best operating conditions for the proposed system.
Yoshinobu Tanaka - One of the best experts on this subject based on the ideXlab platform.
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Ion-exchange Membrane electrodialysis program and its application to multi-stage continuous saline water desalination
Desalination, 2012Co-Authors: Yoshinobu TanakaAbstract:Abstract The first part of this article describes the program of a one-stage continuous electrodialysis process operating at a constant current mode. The full continuous electrodialysis program is developed and explained definitely by arranging equations systematically with the following supplementary steps. For preventing scale formation in concentrating cells, salt solutions supplied to the desalting cells are also fed to the concentrating cells. Influence of temperature to the performance of the electrodialyzer is taken into account. Pressure drop in the electrodialyzer is evaluated by incorporating the functions of hydrodynamic diameters of desalting and concentrating cells and slots. An electric current screening effect of a spacer is determined by the volume ratio of spacer rods in a desalting and concentrating cell. In the second part of this article, saline water is desalinated with the multi-stage electrodialysis program by operating the process at a constant concentration mode. Changing salt concentration of a feeding solution in each stage incrementally, the performances of the electrodialyzer such as; ion and solution flux across a Membrane Pair; cell voltage; current density; salt concentration in concentrating cells; energy consumption; water recovery; limiting current density; pressure drop in the cells and slots are computed in each stage. Energy consumption, water recovery, pressure drop and Membrane area are computed in the total stages to produce drinking water.
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ion exchange Membrane electrodialysis for saline water desalination and its application to seawater concentration
Industrial & Engineering Chemistry Research, 2011Co-Authors: Yoshinobu TanakaAbstract:Membrane Pair characteristics of commercially available ion-exchange Membranes are measured by changing current density and seawater temperature supplied to the electrodialyzer. The hydraulic permeabilities (leading parameter) for three types of commercially available Membranes are almost the same, and their averages are expressed by the empirical function of temperature. Hydraulic osmosis is predominant at lower current density and electro-osmosis is predominant at larger current density. The influence of temperature and salt concentration on the physical properties of saline water, such as solution density, specific conductance, and NaCl activity coefficient, is expressed by empirical equations. Ionic constituents in a concentrated solution are expressed by empirical equations. Electric current screening ratio of a spacer is defined and calculated. Direct current electric resistance of a Membrane Pair is calculated, and it is predominant over that of a desalting cell and a concentrating cell. It is nece...
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irreversible thermodynamics and overall mass transport in ion exchange Membrane electrodialysis
Journal of Membrane Science, 2006Co-Authors: Yoshinobu TanakaAbstract:Abstract An ion-exchange Membrane electrodialysis phenomenon was presented by using phenomenological equation based on the irreversible thermodynamics. The overall mass transport equation was introduced based on the electrodialysis of seawater. The overall mass transport equation was joined to the phenomenological equation by setting both equations are equivalent each other. As the result of this process, the overall Membrane characteristics appeared in the overall mass transport equation (overall transport number λ, overall solute permeability μ, overall electro-osmotic permeability ϕ and overall hydraulic conductivity ρ) were expressed by the function of the irreversible Membrane Pair characteristics appeared in the phenomenological equation (transport number t, solute permeability ω, electro-osmotic permeability β and hydraulic conductivity LP). λ, μ, ϕ, r (electric resistance) and W (water content) were expressed by the empirical function of ρ. Reflection coefficient was discussed by defining the pressure reflection coefficient σ and concentration reflection coefficient σ′. From the pressure dialysis of a KCl solution, σ of an ion-Membrane was generally assumed to be 1. σ′ corresponded with the permselectivity between ions and water molecules across an ion-exchange Membrane at just after electric current interruption (electric current switching off concept), and was expressed by the function of μ, ρ and logarithmic mean concentration C*. t, ω, β, LP, LPD (osmotic volume flow coefficient), LDP (ultrafiltration coefficient) and LD (exchange flow parameter) included in the phenomenological equation were computed by applying the overall mass transport equation to electrodialysis experiments. The influence of concentration polarization upon the overall Membrane characteristics measurement was negligibly small.
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ion exchange Membrane electrodialytic salt production using brine discharged from a reverse osmosis seawater desalination plant
Journal of Membrane Science, 2003Co-Authors: Yoshinobu Tanaka, Reo Ehara, Sigeru Itoi, Totaro GotoAbstract:Abstract Operating parameters of an ion-exchange Membrane electrodialytic salt manufacturing plant (NaCl production capacity: 200,000 t per year) using brine discharged from a reverse osmosis (RO) seawater desalination plant are discussed. The results were compared with the data obtained from a salt manufacturing plant using seawater. The specifications of the electrodialyzer are: the thickness of the desalting cell, 0.05 cm; the flow-pass length in a desalting cell, 2 m; effective Membrane area, 2 m 2 ; overall osmotic coefficient of a Membrane Pair, 30 cm 4 /(eq. h); and solution velocity at the inlets of desalting cells, 5 cm/s. The electrolyte concentration at the inlets of desalting cells was set at 1.5 eq./dm 3 , which is consistent with the electrolyte concentration of brine discharged from a reverse osmosis seawater desalination plant. The energy consumed in the salt manufacturing process was assumed to be supplied by a simultaneous heat-generating electric power unit using a back-pressure turbine. The number of evaporators (evaporation pans) was selected to minimize the electric power shortfall of the salt manufacturing process but to be larger than zero. The electric power shortage was assumed to be made up by purchased electric power, which is generated by a condensing turbine. The energy consumption in a salt manufacturing process was obtained by adding the generation energy in the back-pressure turbine, the evaporation energy in the No. 1 evaporator in multiple-effect evaporators, the condensing energy in the heater in the No. 1 evaporator and purchased energy. The energy consumption in a salt manufacturing process using the brine discharged from a reverse osmosis seawater desalinating plant was 80% of the energy consumption in the process using seawater. The optimum current density at which the energy consumption is minimized was 3 A/dm 2 for both electrodialyses of brine discharged from the reverse osmosis desalination plant and of seawater.
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mass transport and energy consumption in ion exchange Membrane electrodialysis of seawater
Journal of Membrane Science, 2003Co-Authors: Yoshinobu TanakaAbstract:Abstract The theory of ionic transport processes in ion-exchange Membrane electrodialysis system was developed. The fundamentals in this theory is expressed by the overall mass transport equation of ions and a solution across a Membrane Pair. The equation includes overall transport number λ , overall diffusion coefficient μ , overall electro-osmotic coefficient φ and overall osmotic coefficient ρ . These parameters indicate the characteristics of an ion-exchange Membrane Pair placed in an electrolyte solution containing more than two kinds of ions. These parameters were measured by the electrodialysis of seawater. Parameters λ , μ and φ were expressed by empirical functions of ρ . These functions facilitate the simulation of the electrodialytic process. Parameter ρ was found to have the relation to non-equilibrium parameter; filtration coefficient L p . The formulas were obtained in order to express various aspects such as the transport of ions and solutions across Membranes, electrolyte concentration in both a desalting and concentrating cell, desalting ratio of a desalted solution and current efficiency. Ionic constituents in a concentrated solution were also measured by the seawater electrodialysis. The relationship between current density and the equivalent ratio of ions in a concentrated solution was expressed by empirical formulas. Thereby, the concentration of Na + , K + , Mg 2+ , Ca 2+ , Cl − and SO 4 2− ions in a concentrated solution was estimated. The voltage applied to a cell Pair is known to be related to electrical resistance and Membrane potential. The electrical resistance of solutions in a cell Pair was determined by the specific resistance measurement of electrolyte solutions. The direct current electrical resistance of Membranes in a cell Pair was measured by the seawater electrodialysis. The effect of concentration polarization on the voltage applied to a cell Pair is seen in the direct current resistance of the Membrane. Energy consumption during the process of seawater electrodialysis was evaluated using the function of the voltage applied to a cell Pair. The energy consumption, the limiting current density and the saturation current density are discussed on the basis that the current density and solution velocity (electrolyte concentration) in desalting cells are distributed in an electrodialyzer.
Ramato Ashu Tufa - One of the best experts on this subject based on the ideXlab platform.
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salinity gradient power reverse electrodialysis cation exchange Membrane design based on polypyrrole chitosan composites for enhanced monovalent selectivity
Chemical Engineering Journal, 2020Co-Authors: Ramato Ashu Tufa, Jaromír Hnát, Debabrata Chanda, Enrica Fontananova, Efrem Curcio, Gianluca Di Profio, Theo Piallat, Martin Paidar, Karel BouzekAbstract:Abstract Reverse electrodialysis (RED) is one of the most promising Membrane-based processes for renewable energy generation from mixing two solutions of different salinity. However, the presence of Mg2+ in natural water has been shown to drastically reduce open circuit voltage (OCV) and output power of RED. To alleviate this challenge, commercial cation exchange Membranes (CEM) supplied by Fujifilm Manufacturing Europe B.V. (The Netherlands) were chemically modified by polypyrrole (PPy)/chitosan (CS) composites under controlled Pyrrole (Py) concentration (0.025–1 M) and polymerization time (0–8 h). The modified Membranes were physically characterized by FTIR, SEM and EDX along with the determination of key electrochemical properties like ion exchange capacity, ionic conductivity, monovalent selectivity and swelling degree. The monovalent selectivity (Na+ vs Mg2+) of the modified Membranes, evaluated based on flux of ions by diffusion dialysis, indicated up to 3-fold improvement compared to pristine Membranes inline with the enhanced OCV (up to 20%) during RED test in multi-ion solution. This was obtained without significant change in Membrane and interface resistances as depicted by electrochemical impedance spectroscopy. The modified Membranes displayed power densities in the range of 0.6–1.5 W/m2MP (MP: Membrane Pair) with more than 42% improvement compared to pristine Membranes during RED test with multi-ion solutions. Although there is a gap for further improvement, these findings highlight a promising use of conducting polymers to design a highly selective and conductive Membrane for RED.
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effect of mg2 ions on energy generation by reverse electrodialysis
Journal of Membrane Science, 2016Co-Authors: Ahmet H Avci, Pinkey Sarkar, Diego Messana, Pietro Argurio, Ramato Ashu Tufa, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract Reverse Electrodialysis is today recognized as one of the most promising technology to harvest Salinity Gradient Power (SGP-RE). However, the effectiveness of SGP-RE in real practice is still not clearly defined due to the lack of specific studies in literature, being in large part limited to investigations on pure NaCl solutions. In this work we experimentally investigated the effect of Mg2+, the most abundant cation in natural water after Na+, on SGP-RE performance by power measurements on a lab-scale stack prototype. Maximum power density ranged from 1.06 W/m2MP (MP: Membrane Pair) - generated when feeding SGP-RE prototype with 0.5 molal//4 molal NaCl, to 0.06 W/m2MP - measured when using 0.5 molal//4 molal MgCl2 solutions. Likewise, open circuit voltage decreased from 1.70 to 0.72 V. Evidence of uphill transport in the range of 0–30% MgCl2 was confirmed by Ion Chromatography analysis carried out on inlet and outlet streams of SGP-RE stack. Electrochemical Impedance Spectroscopy analysis revealed that cation exchange Membrane resistance was critically affected by Mg2+ concentration: Membrane resistance, from a value of 2.41 Ω cm2 in pure NaCl solution, increased tenfold in pure MgCl2 solution.
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Salinity gradient power-reverse electrodialysis and alkaline polymer electrolyte water electrolysis for hydrogen production
Journal of Membrane Science, 2016Co-Authors: Ramato Ashu Tufa, Jaromír Hnát, Debabrata Chanda, Elisabetta Rugiero, J Veerman, Willem Van Baak, Enrica Fontananova, Gianluca Di Profio, Enrico Drioli, Karel BouzekAbstract:Abstract In this work, innovative use of Salinity Gradient Power (SGP) as renewable energy source for indirect production of hydrogen is addressed. A lab-scale reverse electrodialysis (RED) unit, fed with different NaCl solutions mimicking highly concentrated brine (5 M), Reverse Osmosis retentate (1 M), seawater (0.5 M) and brackish water (0.1 M), was coupled to an alkaline polymer electrolyte (APE) water electrolysis cell. SGP-RED unit, equipped with 27 cell-Pairs, reached at best an Open Circuit Voltage (OCV) of 3.7 V and maximum gross power density of 3.2 W m −2 MP (Membrane Pair) when feeding the low concentration compartment (LCC) with 0.1 M NaCl and the High Concentration Compartment (HCC) with 5 M NaCl. The single-cell APE water electrolysis unit, operated at 1.8 V, attained a current density of 120 mA cm −2 under the following configuration: 10% w/w KOH electrolyte, highly conductive anion selective Membrane composed of inert low-density polyethylene, finely milled anion selective particles and water-soluble poly (ethylene glycol-ran-propylene glycol), non-Platinum catalysts (NiCo 2 O 4 and NiFe 2 O 4 ) loading of 10 mg cm −2 and 15%w/w polymer binder at both cathode and anode, and operational temperature of 65 °C. The integrated system resulted in a maximum hydrogen production rate of 44 cm 3 h −1 per cm 2 of electrode surface area.
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Membrane distillation and reverse electrodialysis for near zero liquid discharge and low energy seawater desalination
Journal of Membrane Science, 2015Co-Authors: Ramato Ashu Tufa, E Brauns, Willem Van Baak, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract With a total capacity of 70 million cubic meters per day, seawater desalination industry represents the most affordable source of drinking water for many people living in arid areas of the world. Seawater Reverse Osmosis (SWRO) technology, driven by the impressive development in Membrane materials, modules and process design, currently shows an overall energy consumption of 3–4 kW h per m 3 of desalted water, substantially lower than thermal systems; however, the theoretical energy demand to produce 1 m 3 of potable water from 2 m 3 of seawater (50% recovery factor) is 1.1 kW h. In order to move towards this goal, the possibility to recover the energy content of discharged concentrates assumes a strategic relevance. In this work, an innovative approach combining Direct Contact Membrane Distillation (DCMD) and Reverse Electrodialysis (RE) is tested for simultaneous water and energy production from SWRO brine, thus implementing the concept of low energy and Near-Zero Liquid Discharge in seawater desalination. DCMD operated on 1 M NaCl RO retentate fed at 40–50 °C resulted in a Volume Reduction Factor (VRF) up to 83.6% with transMembrane flux in the range of 1.2–2.4 kg/m 2 h. The performance of RE stack fed with DCMD brine (4–5.4 M) and seawater (0.5 M) was investigated at different temperatures (10–45 °C) and flow velocities (0.7–1.1 cm/s). Experimental data show the possibility to obtain an Open Circuit Voltage (OCV) in the range of 1.5–2.3 V and a gross power density of 0.9–2.4 W / m MP 2 (Membrane Pair). In general, optimization is required to find best operating conditions for the proposed system.
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Membrane distillation and reverse electrodialysis for near zero liquid discharge and low energy seawater desalination
Journal of Membrane Science, 2015Co-Authors: Ramato Ashu Tufa, E Brauns, Willem Van Baak, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract With a total capacity of 70 million cubic meters per day, seawater desalination industry represents the most affordable source of drinking water for many people living in arid areas of the world. Seawater Reverse Osmosis (SWRO) technology, driven by the impressive development in Membrane materials, modules and process design, currently shows an overall energy consumption of 3–4 kW h per m 3 of desalted water, substantially lower than thermal systems; however, the theoretical energy demand to produce 1 m 3 of potable water from 2 m 3 of seawater (50% recovery factor) is 1.1 kW h. In order to move towards this goal, the possibility to recover the energy content of discharged concentrates assumes a strategic relevance. In this work, an innovative approach combining Direct Contact Membrane Distillation (DCMD) and Reverse Electrodialysis (RE) is tested for simultaneous water and energy production from SWRO brine, thus implementing the concept of low energy and Near-Zero Liquid Discharge in seawater desalination. DCMD operated on 1 M NaCl RO retentate fed at 40–50 °C resulted in a Volume Reduction Factor (VRF) up to 83.6% with transMembrane flux in the range of 1.2–2.4 kg/m 2 h. The performance of RE stack fed with DCMD brine (4–5.4 M) and seawater (0.5 M) was investigated at different temperatures (10–45 °C) and flow velocities (0.7–1.1 cm/s). Experimental data show the possibility to obtain an Open Circuit Voltage (OCV) in the range of 1.5–2.3 V and a gross power density of 0.9–2.4 W / m MP 2 (Membrane Pair). In general, optimization is required to find best operating conditions for the proposed system.
Enrica Fontananova - One of the best experts on this subject based on the ideXlab platform.
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salinity gradient power reverse electrodialysis cation exchange Membrane design based on polypyrrole chitosan composites for enhanced monovalent selectivity
Chemical Engineering Journal, 2020Co-Authors: Ramato Ashu Tufa, Jaromír Hnát, Debabrata Chanda, Enrica Fontananova, Efrem Curcio, Gianluca Di Profio, Theo Piallat, Martin Paidar, Karel BouzekAbstract:Abstract Reverse electrodialysis (RED) is one of the most promising Membrane-based processes for renewable energy generation from mixing two solutions of different salinity. However, the presence of Mg2+ in natural water has been shown to drastically reduce open circuit voltage (OCV) and output power of RED. To alleviate this challenge, commercial cation exchange Membranes (CEM) supplied by Fujifilm Manufacturing Europe B.V. (The Netherlands) were chemically modified by polypyrrole (PPy)/chitosan (CS) composites under controlled Pyrrole (Py) concentration (0.025–1 M) and polymerization time (0–8 h). The modified Membranes were physically characterized by FTIR, SEM and EDX along with the determination of key electrochemical properties like ion exchange capacity, ionic conductivity, monovalent selectivity and swelling degree. The monovalent selectivity (Na+ vs Mg2+) of the modified Membranes, evaluated based on flux of ions by diffusion dialysis, indicated up to 3-fold improvement compared to pristine Membranes inline with the enhanced OCV (up to 20%) during RED test in multi-ion solution. This was obtained without significant change in Membrane and interface resistances as depicted by electrochemical impedance spectroscopy. The modified Membranes displayed power densities in the range of 0.6–1.5 W/m2MP (MP: Membrane Pair) with more than 42% improvement compared to pristine Membranes during RED test with multi-ion solutions. Although there is a gap for further improvement, these findings highlight a promising use of conducting polymers to design a highly selective and conductive Membrane for RED.
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effect of mg2 ions on energy generation by reverse electrodialysis
Journal of Membrane Science, 2016Co-Authors: Ahmet H Avci, Pinkey Sarkar, Diego Messana, Pietro Argurio, Ramato Ashu Tufa, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract Reverse Electrodialysis is today recognized as one of the most promising technology to harvest Salinity Gradient Power (SGP-RE). However, the effectiveness of SGP-RE in real practice is still not clearly defined due to the lack of specific studies in literature, being in large part limited to investigations on pure NaCl solutions. In this work we experimentally investigated the effect of Mg2+, the most abundant cation in natural water after Na+, on SGP-RE performance by power measurements on a lab-scale stack prototype. Maximum power density ranged from 1.06 W/m2MP (MP: Membrane Pair) - generated when feeding SGP-RE prototype with 0.5 molal//4 molal NaCl, to 0.06 W/m2MP - measured when using 0.5 molal//4 molal MgCl2 solutions. Likewise, open circuit voltage decreased from 1.70 to 0.72 V. Evidence of uphill transport in the range of 0–30% MgCl2 was confirmed by Ion Chromatography analysis carried out on inlet and outlet streams of SGP-RE stack. Electrochemical Impedance Spectroscopy analysis revealed that cation exchange Membrane resistance was critically affected by Mg2+ concentration: Membrane resistance, from a value of 2.41 Ω cm2 in pure NaCl solution, increased tenfold in pure MgCl2 solution.
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Salinity gradient power-reverse electrodialysis and alkaline polymer electrolyte water electrolysis for hydrogen production
Journal of Membrane Science, 2016Co-Authors: Ramato Ashu Tufa, Jaromír Hnát, Debabrata Chanda, Elisabetta Rugiero, J Veerman, Willem Van Baak, Enrica Fontananova, Gianluca Di Profio, Enrico Drioli, Karel BouzekAbstract:Abstract In this work, innovative use of Salinity Gradient Power (SGP) as renewable energy source for indirect production of hydrogen is addressed. A lab-scale reverse electrodialysis (RED) unit, fed with different NaCl solutions mimicking highly concentrated brine (5 M), Reverse Osmosis retentate (1 M), seawater (0.5 M) and brackish water (0.1 M), was coupled to an alkaline polymer electrolyte (APE) water electrolysis cell. SGP-RED unit, equipped with 27 cell-Pairs, reached at best an Open Circuit Voltage (OCV) of 3.7 V and maximum gross power density of 3.2 W m −2 MP (Membrane Pair) when feeding the low concentration compartment (LCC) with 0.1 M NaCl and the High Concentration Compartment (HCC) with 5 M NaCl. The single-cell APE water electrolysis unit, operated at 1.8 V, attained a current density of 120 mA cm −2 under the following configuration: 10% w/w KOH electrolyte, highly conductive anion selective Membrane composed of inert low-density polyethylene, finely milled anion selective particles and water-soluble poly (ethylene glycol-ran-propylene glycol), non-Platinum catalysts (NiCo 2 O 4 and NiFe 2 O 4 ) loading of 10 mg cm −2 and 15%w/w polymer binder at both cathode and anode, and operational temperature of 65 °C. The integrated system resulted in a maximum hydrogen production rate of 44 cm 3 h −1 per cm 2 of electrode surface area.
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Membrane distillation and reverse electrodialysis for near zero liquid discharge and low energy seawater desalination
Journal of Membrane Science, 2015Co-Authors: Ramato Ashu Tufa, E Brauns, Willem Van Baak, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract With a total capacity of 70 million cubic meters per day, seawater desalination industry represents the most affordable source of drinking water for many people living in arid areas of the world. Seawater Reverse Osmosis (SWRO) technology, driven by the impressive development in Membrane materials, modules and process design, currently shows an overall energy consumption of 3–4 kW h per m 3 of desalted water, substantially lower than thermal systems; however, the theoretical energy demand to produce 1 m 3 of potable water from 2 m 3 of seawater (50% recovery factor) is 1.1 kW h. In order to move towards this goal, the possibility to recover the energy content of discharged concentrates assumes a strategic relevance. In this work, an innovative approach combining Direct Contact Membrane Distillation (DCMD) and Reverse Electrodialysis (RE) is tested for simultaneous water and energy production from SWRO brine, thus implementing the concept of low energy and Near-Zero Liquid Discharge in seawater desalination. DCMD operated on 1 M NaCl RO retentate fed at 40–50 °C resulted in a Volume Reduction Factor (VRF) up to 83.6% with transMembrane flux in the range of 1.2–2.4 kg/m 2 h. The performance of RE stack fed with DCMD brine (4–5.4 M) and seawater (0.5 M) was investigated at different temperatures (10–45 °C) and flow velocities (0.7–1.1 cm/s). Experimental data show the possibility to obtain an Open Circuit Voltage (OCV) in the range of 1.5–2.3 V and a gross power density of 0.9–2.4 W / m MP 2 (Membrane Pair). In general, optimization is required to find best operating conditions for the proposed system.
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Membrane distillation and reverse electrodialysis for near zero liquid discharge and low energy seawater desalination
Journal of Membrane Science, 2015Co-Authors: Ramato Ashu Tufa, E Brauns, Willem Van Baak, Enrica Fontananova, Efrem Curcio, Gianluca Di ProfioAbstract:Abstract With a total capacity of 70 million cubic meters per day, seawater desalination industry represents the most affordable source of drinking water for many people living in arid areas of the world. Seawater Reverse Osmosis (SWRO) technology, driven by the impressive development in Membrane materials, modules and process design, currently shows an overall energy consumption of 3–4 kW h per m 3 of desalted water, substantially lower than thermal systems; however, the theoretical energy demand to produce 1 m 3 of potable water from 2 m 3 of seawater (50% recovery factor) is 1.1 kW h. In order to move towards this goal, the possibility to recover the energy content of discharged concentrates assumes a strategic relevance. In this work, an innovative approach combining Direct Contact Membrane Distillation (DCMD) and Reverse Electrodialysis (RE) is tested for simultaneous water and energy production from SWRO brine, thus implementing the concept of low energy and Near-Zero Liquid Discharge in seawater desalination. DCMD operated on 1 M NaCl RO retentate fed at 40–50 °C resulted in a Volume Reduction Factor (VRF) up to 83.6% with transMembrane flux in the range of 1.2–2.4 kg/m 2 h. The performance of RE stack fed with DCMD brine (4–5.4 M) and seawater (0.5 M) was investigated at different temperatures (10–45 °C) and flow velocities (0.7–1.1 cm/s). Experimental data show the possibility to obtain an Open Circuit Voltage (OCV) in the range of 1.5–2.3 V and a gross power density of 0.9–2.4 W / m MP 2 (Membrane Pair). In general, optimization is required to find best operating conditions for the proposed system.