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William G Johnson - One of the best experts on this subject based on the ideXlab platform.
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efficacy of dicamba and glyphosate as influenced by Carrier Water ph and hardness
Weed Technology, 2020Co-Authors: Pratap Devkota, William G JohnsonAbstract:Herbicide Carrier Water hardness and pH can be variable depending on the source and geographic location. Herbicide efficacy can be affected by the pH and hardness of Water used for spray solution. Field and greenhouse studies were conducted to evaluate the effect of Carrier Water pH and hardness on premixed dicamba and glyphosate efficacy. Treatments were combinations of Water pH at 4, 6.5, or 9; and Water hardness at 0 (deionized Water), 400, or 800 mg L–1 of CaCO3 equivalent. In the field study, dicamba and glyphosate were applied at 0.55 and 1.11 kg ae ha–1, respectively, and half of these rates were applied in the greenhouse study. There was no interaction between Carrier Water pH and hardness on dicamba and glyphosate efficacy; however, the main effects of Carrier Water pH and hardness were significant. Herbicide efficacy was reduced with Carrier Water at pH 9 compared with pH 4. In the field study, common lambsquarters, common ragweed, horseweed, or Palmer amaranth control was improved 6% or more at Carrier Water at pH 4 compared with pH 9. Similar results were observed with Water pH for giant ragweed, Palmer amaranth, or pitted morningglory control in the greenhouse study. Carrier Water hardness at 400 or 800 mg L–1 reduced common ragweed, giant ragweed, or horseweed control compared with 0 mg L–1. Similarly, common lambsquarters, Palmer amaranth, or pitted morningglory control was reduced at least 10% with Carrier Water hardness at 800 mg L–1 compared with 0 mg L–1. These results indicate Carrier Water at acidic pH and of no hardness is critical for dicamba and glyphosate application, and spray solution needs to be amended appropriately for an optimum efficacy.Nomenclature: Dicamba; glyphosate; common lambsquarters, Chenopodium album L. CHEAL; common ragweed, Ambrosia artemisiifolia L. AMBEL; giant ragweed, Ambrosia trifida L. AMBTR; horseweed, Conyza canadensis (L.) Cronq. ERICA; Palmer amaranth, Amaranthus palmeri (S.) Watson AMAPA; pitted morningglory, Ipomoea lacunosa L. IPOLA
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Influence of Carrier Water pH, foliar fertilizer, and ammonium sulfate on 2,4-D and 2,4-D plus glyphosate efficacy
Weed Technology, 2019Co-Authors: Pratap Devkota, William G JohnsonAbstract:Carrier Water pH is an important factor for enhancing herbicide efficacy. Coapplying agrochemical products with the herbicide might save time and resources; however, the negative effect of foliar fertilizers on herbicide efficacy should be thoroughly evaluated. In greenhouse studies, the effect of Carrier Water pH (4, 6.5, and 9), foliar fertilizer (zinc [Zn], manganese [Mn], or without fertilizer), and ammonium sulfate (AMS) at 0% or 2.5% vol/vol was evaluated on 2,4-D and premixed 2,4-D plus glyphosate efficacy for giant ragweed, horseweed, and Palmer amaranth control. In addition, a field study was conducted to evaluate the effect of Carrier Water pH (4, 6.5, and 9); and Zn or Mn foliar fertilizer on premixed 2,4-D plus glyphosate efficacy for horseweed and Palmer amaranth control. In the greenhouse study, 2,4-D and premixed 2,4-D plus glyphosate provided 5% greater weed control at acidic compared with alkaline Carrier Water pH. Coapplied Mn foliar fertilizer reduced 2,4-D and premixed 2,4-D plus glyphosate efficacy at least 5% for weed control. Addition of AMS enhanced 2,4-D and premixed 2,4-D plus glyphosate efficacy at least 6% for giant ragweed, horseweed, and Palmer amaranth control. In the field study, few significant differences occurred between coapplied Zn or Mn foliar fertilizer for any treatment variables. Therefore, Carrier Water pH, coapplied foliar fertilizer, and Water-conditioning adjuvants have potential to influence herbicide performance. However, weed species could play a role in the differential response of these factors on herbicide efficacy.Nomenclature: 2,4-D; glyphosate; giant ragweed, Ambrosia trifida L. AMBTR; horseweed, Erigeron canadensis (L.) ERICA; Palmer amaranth, Amaranthus palmeri S. Watson AMAPA
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influence of spray solution temperature and holding duration on weed control with premixed glyphosate and dicamba formulation
Weed Technology, 2016Co-Authors: Pratap Devkota, Fred Whitford, William G JohnsonAbstract:Water is the primary Carrier for herbicide application, and Carrier-Water–related factors can influence herbicide performance. In a greenhouse study, premixed formulation of glyphosate plus dicamba was mixed in deionized (DI) Water at 5, 18, 31, 44, or 57 C and applied immediately. In a companion study, glyphosate and dicamba formulation was mixed in DI Water at temperatures of 5, 22, 39, or 56 C and sprayed after the herbicide solution was left at the respective temperatures for 0, 6, or 24 h. In both studies, glyphosate plus dicamba was applied at 0.275 plus 0.137 kg ae ha−1 (low rate), and 0.55 plus 0.275 kg ha−1 (high rate), respectively, to giant ragweed, horseweed, Palmer amaranth, and pitted morningglory. Glyphosate plus dicamba applied at a low rate with solution temperature of 31 C provided 14% and 26% greater control of giant ragweed and pitted morningglory, respectively, compared to application at solution temperature of 5 C. At both rates of glyphosate and dicamba formulation, giant ragweed an...
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Glufosinate Efficacy as Influenced by Carrier Water pH, Hardness, Foliar Fertilizer, and Ammonium Sulfate
Weed Technology, 2016Co-Authors: Pratap Devkota, William G JohnsonAbstract:Carrier Water quality is an important consideration for herbicide efficacy. Effect of Carrier Water pH (4, 6.5, or 9) and coapplied Zn or Mn foliar fertilizer was evaluated on glufosinate efficacy for horseweed and Palmer amaranth control in the field. Greenhouse studies were conducted to evaluate the effect of: (1) Carrier Water pH, foliar fertilizer (Zn, Mn, or without fertilizer), and ammonium sulfate (AMS) (at 0 or 2.5% v/v); and (2) Carrier Water hardness (0 to 1,000 mg L−1) and AMS (at 0 or 2.5% v/v) on glufosinate efficacy for giant ragweed, horseweed, and Palmer amaranth control. In a 2014 field study, control, plant density reduction, and biomass reduction were at least 8% greater for horseweed and at least 14% greater for Palmer amaranth when glufosinate was applied at Carrier Water pH 4 compared with pH 9. Glufosinate efficacy was at least 10 and 17% greater for giant ragweed and Palmer amaranth control, respectively, with Carrier Water pH 4 compared with pH 9 in the greenhouse. In the greenhou...
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Influence of Carrier Water pH, Hardness, Foliar Fertilizer, and Ammonium Sulfate on Mesotrione Efficacy
Weed Technology, 2016Co-Authors: Pratap Devkota, Douglas J. Spaunhorst, William G JohnsonAbstract:Carrier Water pH, hardness, coapplied foliar fertilizer, Water conditioning agents, and plant height are critical considerations for optimum herbicide performance. Field studies were conducted to evaluate the effect of Carrier Water pH (4, 6.5, and 9) and zinc (Zn) or manganese (Mn) foliar fertilizer on mesotrione for horseweed and Palmer amaranth control. Additionally, effect of Carrier Water pH and foliar fertilizer was evaluated on 7.5-, 12.5-, and 17.5-cm tall horseweed. Greenhouse treatments consisted of Carrier Water pH and foliar fertilizer (Zn, Mn, or without fertilizer); or Water hardness (0 to 1,000 mg L−1) in the presence or absence of ammonium sulfate (AMS) for mesotrione control of giant ragweed, horseweed, and Palmer amaranth. Mesotrione activity was greater on horseweed with Carrier Water pH 6.5 compared to pH 4 or 9. Coapplied Zn fertilizer reduced mesotrione activity on Palmer amaranth in the field study in 2014 and horseweed in the greenhouse study. Mesotrione efficacy was greatly influe...
David P Wilkinson - One of the best experts on this subject based on the ideXlab platform.
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Production of Hydrogen Peroxide for Drinking Water Treatment in a Proton Exchange Membrane Electrolyzer at Near-Neutral pH
Journal of The Electrochemical Society, 2020Co-Authors: Arman Bonakdarpour, Előd L Gyenge, David P WilkinsonAbstract:We provide a detailed report on the electrosynthesis of H2O2 for drinking Water treatment under near-neutral conditions using a proton exchange membrane (PEM) electrolyzer. Two novel cathode catalysts for O2 electroreduction to H2O2 were investigated in the PEM electrolyzer: an inorganic cobalt-carbon (Co–C) composite and an organic redox catalyst anthraquinone-riboflavinyl mixed with carbon (AQ–C), respectively. The impact of operational variables such as temperature, cathode Carrier Water flow rate, and anode configurations (aimed at mitigating carbon corrosion at the anode) were examined in single-pass and full recycle operation. Using a superficial current density of 245 mA cm−2 and an operating temperature of 40 °C, H2O2 molar fluxes of 360 μmol hr−1 cm−2 and 580 μmol hr−1 cm−2 were generated at near-neutral pH with the Co–C and RF-AQ catalysts, respectively. Seventy-two hour experiments with closed loop recirculation, produced H2O2 concentrations of 1300 and 3000 ppm for the Co–C and AQ–C catalysts, respectively. These concentrations are adequate for advanced oxidation (UV/H2O2) treatment of drinking Water, rendering the PEM electrolysis approach particularly suitable for on-site and on-demand production of H2O2.
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Design of bifunctional electrodes for co-generation of electrical power and hydrogen peroxide
Journal of Applied Electrochemistry, 2018Co-Authors: Arman Bonakdarpour, Előd L Gyenge, David P WilkinsonAbstract:We present a method of co-generating hydrogen peroxide and electrical power via the two-electron cathodic reduction of oxygen in a H_2/O_2 proton exchange membrane fuel cell (PEMFC). The cell uses a continuous flow of Carrier Water through its cathodic chamber to remove the hydrogen peroxide product at a neutral pH. To improve the co-generation of electric power and hydrogen peroxide, a number of different cathode configurations, using both four- and two-electron oxygen reducing electrocatalysts, were constructed and examined. With a bifunctional cathode structure consisting of side-by-side carbon-supported Pt– and Co–C-based catalyst layers, and a carbon-based micro-porous layer (MPL), a hydrogen peroxide generation flux of 8 µmol h^−1 cm^−2 is achieved. The corresponding power density is about 133 mW cm^−2. The co-generation of power and hydrogen peroxide could be used in a variety of applications, including the on-site production of hydrogen peroxide for Water treatment by advanced oxidation processes. Graphical Abstract
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Drinking Water Purification by Electrosynthesis of Hydrogen Peroxide in a Power‐Producing PEM Fuel Cell
Chemsuschem, 2013Co-Authors: Winton Li, Előd L Gyenge, Arman Bonakdarpour, David P WilkinsonAbstract:The industrial anthraquinone auto-oxidation process produces most of the world’s supply of hydrogen peroxide. For applications that require small amounts of H2O2 or have economically difficult transportation means, an alternate, on-site H2O2 production method is needed. Advanced drinking Water purification technologies use neutral-pH H2O2 in combination with UV treatment to reach the desired Water purity targets. To produce neutral H2O2 on-site and on-demand for drinking Water purification, the electroreduction of oxygen at the cathode of a proton exchange membrane (PEM) fuel cell operated in either electrolysis (power consuming) or fuel cell (power generating) mode could be a possible solution. The work presented here focuses on the H2/O2 fuel cell mode to produce H2O2. The fuel cell reactor is operated with a continuous flow of Carrier Water through the cathode to remove the product H2O2. The impact of the cobalt–carbon composite cathode catalyst loading, Teflon content in the cathode gas diffusion layer, and cathode Carrier Water flowrate on the production of H2O2 are examined. H2O2 production rates of up to 200 μmol h−1 cmgeometric −2 are achieved using a continuous flow of Carrier Water operating at 30 % current efficiency. Operation times of more than 24 h have shown consistent H2O2 and power production, with no degradation of the cobalt catalyst.
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Drinking Water purification by electrosynthesis of hydrogen peroxide in a power-producing PEM fuel cell.
ChemSusChem, 2013Co-Authors: Arman Bonakdarpour, Előd L Gyenge, David P WilkinsonAbstract:The industrial anthraquinone auto-oxidation process produces most of the world's supply of hydrogen peroxide. For applications that require small amounts of H2 O2 or have economically difficult transportation means, an alternate, on-site H2 O2 production method is needed. Advanced drinking Water purification technologies use neutral-pH H2 O2 in combination with UV treatment to reach the desired Water purity targets. To produce neutral H2 O2 on-site and on-demand for drinking Water purification, the electroreduction of oxygen at the cathode of a proton exchange membrane (PEM) fuel cell operated in either electrolysis (power consuming) or fuel cell (power generating) mode could be a possible solution. The work presented here focuses on the H2 /O2 fuel cell mode to produce H2 O2 . The fuel cell reactor is operated with a continuous flow of Carrier Water through the cathode to remove the product H2 O2 . The impact of the cobalt-carbon composite cathode catalyst loading, Teflon content in the cathode gas diffusion layer, and cathode Carrier Water flowrate on the production of H2 O2 are examined. H2 O2 production rates of up to 200 μmol h(-1) cmgeometric (-2) are achieved using a continuous flow of Carrier Water operating at 30 % current efficiency. Operation times of more than 24 h have shown consistent H2 O2 and power production, with no degradation of the cobalt catalyst.
Jia Gui-qin - One of the best experts on this subject based on the ideXlab platform.
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Study on removal of Water-soluble polyvinyl alcohol fiber in Water-soluble polyvinyl alcohol fiber/wool yarn and its fabric
Wool textile journal, 2008Co-Authors: Jia Gui-qinAbstract:The textile technology with Carrier Water-soluble polyvinyl alcohol fiber for wool fabric play an important role in the development of lightweight worsted fabric.It can get the yarn liner density and the fabric weight decrease by thoroughly removing Water-soluble polyvinyl alcohol fibers in fabric finishing processing,lightweight fabric.The removal of Water-soluble polyvinyl alcohol fibers in Water-soluble polyvinyl alcohol fiber/wool yarn and its fabric were investigated.Experimental results showed that the relationship between the removal ratios of Water-soluble polyvinyl alcohol fibers in Water-soluble polyvinyl alcohol fiber/wool yarn and its fabric and Water treatment time were quadratic equation respectively,when put samples at Water temperature(20 ℃) and heated Water and samples at the same rate.The interrelation coefficient R~20.99,but the relation equations were different.
Pratap Devkota - One of the best experts on this subject based on the ideXlab platform.
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efficacy of dicamba and glyphosate as influenced by Carrier Water ph and hardness
Weed Technology, 2020Co-Authors: Pratap Devkota, William G JohnsonAbstract:Herbicide Carrier Water hardness and pH can be variable depending on the source and geographic location. Herbicide efficacy can be affected by the pH and hardness of Water used for spray solution. Field and greenhouse studies were conducted to evaluate the effect of Carrier Water pH and hardness on premixed dicamba and glyphosate efficacy. Treatments were combinations of Water pH at 4, 6.5, or 9; and Water hardness at 0 (deionized Water), 400, or 800 mg L–1 of CaCO3 equivalent. In the field study, dicamba and glyphosate were applied at 0.55 and 1.11 kg ae ha–1, respectively, and half of these rates were applied in the greenhouse study. There was no interaction between Carrier Water pH and hardness on dicamba and glyphosate efficacy; however, the main effects of Carrier Water pH and hardness were significant. Herbicide efficacy was reduced with Carrier Water at pH 9 compared with pH 4. In the field study, common lambsquarters, common ragweed, horseweed, or Palmer amaranth control was improved 6% or more at Carrier Water at pH 4 compared with pH 9. Similar results were observed with Water pH for giant ragweed, Palmer amaranth, or pitted morningglory control in the greenhouse study. Carrier Water hardness at 400 or 800 mg L–1 reduced common ragweed, giant ragweed, or horseweed control compared with 0 mg L–1. Similarly, common lambsquarters, Palmer amaranth, or pitted morningglory control was reduced at least 10% with Carrier Water hardness at 800 mg L–1 compared with 0 mg L–1. These results indicate Carrier Water at acidic pH and of no hardness is critical for dicamba and glyphosate application, and spray solution needs to be amended appropriately for an optimum efficacy.Nomenclature: Dicamba; glyphosate; common lambsquarters, Chenopodium album L. CHEAL; common ragweed, Ambrosia artemisiifolia L. AMBEL; giant ragweed, Ambrosia trifida L. AMBTR; horseweed, Conyza canadensis (L.) Cronq. ERICA; Palmer amaranth, Amaranthus palmeri (S.) Watson AMAPA; pitted morningglory, Ipomoea lacunosa L. IPOLA
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Influence of Carrier Water pH, foliar fertilizer, and ammonium sulfate on 2,4-D and 2,4-D plus glyphosate efficacy
Weed Technology, 2019Co-Authors: Pratap Devkota, William G JohnsonAbstract:Carrier Water pH is an important factor for enhancing herbicide efficacy. Coapplying agrochemical products with the herbicide might save time and resources; however, the negative effect of foliar fertilizers on herbicide efficacy should be thoroughly evaluated. In greenhouse studies, the effect of Carrier Water pH (4, 6.5, and 9), foliar fertilizer (zinc [Zn], manganese [Mn], or without fertilizer), and ammonium sulfate (AMS) at 0% or 2.5% vol/vol was evaluated on 2,4-D and premixed 2,4-D plus glyphosate efficacy for giant ragweed, horseweed, and Palmer amaranth control. In addition, a field study was conducted to evaluate the effect of Carrier Water pH (4, 6.5, and 9); and Zn or Mn foliar fertilizer on premixed 2,4-D plus glyphosate efficacy for horseweed and Palmer amaranth control. In the greenhouse study, 2,4-D and premixed 2,4-D plus glyphosate provided 5% greater weed control at acidic compared with alkaline Carrier Water pH. Coapplied Mn foliar fertilizer reduced 2,4-D and premixed 2,4-D plus glyphosate efficacy at least 5% for weed control. Addition of AMS enhanced 2,4-D and premixed 2,4-D plus glyphosate efficacy at least 6% for giant ragweed, horseweed, and Palmer amaranth control. In the field study, few significant differences occurred between coapplied Zn or Mn foliar fertilizer for any treatment variables. Therefore, Carrier Water pH, coapplied foliar fertilizer, and Water-conditioning adjuvants have potential to influence herbicide performance. However, weed species could play a role in the differential response of these factors on herbicide efficacy.Nomenclature: 2,4-D; glyphosate; giant ragweed, Ambrosia trifida L. AMBTR; horseweed, Erigeron canadensis (L.) ERICA; Palmer amaranth, Amaranthus palmeri S. Watson AMAPA
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influence of spray solution temperature and holding duration on weed control with premixed glyphosate and dicamba formulation
Weed Technology, 2016Co-Authors: Pratap Devkota, Fred Whitford, William G JohnsonAbstract:Water is the primary Carrier for herbicide application, and Carrier-Water–related factors can influence herbicide performance. In a greenhouse study, premixed formulation of glyphosate plus dicamba was mixed in deionized (DI) Water at 5, 18, 31, 44, or 57 C and applied immediately. In a companion study, glyphosate and dicamba formulation was mixed in DI Water at temperatures of 5, 22, 39, or 56 C and sprayed after the herbicide solution was left at the respective temperatures for 0, 6, or 24 h. In both studies, glyphosate plus dicamba was applied at 0.275 plus 0.137 kg ae ha−1 (low rate), and 0.55 plus 0.275 kg ha−1 (high rate), respectively, to giant ragweed, horseweed, Palmer amaranth, and pitted morningglory. Glyphosate plus dicamba applied at a low rate with solution temperature of 31 C provided 14% and 26% greater control of giant ragweed and pitted morningglory, respectively, compared to application at solution temperature of 5 C. At both rates of glyphosate and dicamba formulation, giant ragweed an...
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Glufosinate Efficacy as Influenced by Carrier Water pH, Hardness, Foliar Fertilizer, and Ammonium Sulfate
Weed Technology, 2016Co-Authors: Pratap Devkota, William G JohnsonAbstract:Carrier Water quality is an important consideration for herbicide efficacy. Effect of Carrier Water pH (4, 6.5, or 9) and coapplied Zn or Mn foliar fertilizer was evaluated on glufosinate efficacy for horseweed and Palmer amaranth control in the field. Greenhouse studies were conducted to evaluate the effect of: (1) Carrier Water pH, foliar fertilizer (Zn, Mn, or without fertilizer), and ammonium sulfate (AMS) (at 0 or 2.5% v/v); and (2) Carrier Water hardness (0 to 1,000 mg L−1) and AMS (at 0 or 2.5% v/v) on glufosinate efficacy for giant ragweed, horseweed, and Palmer amaranth control. In a 2014 field study, control, plant density reduction, and biomass reduction were at least 8% greater for horseweed and at least 14% greater for Palmer amaranth when glufosinate was applied at Carrier Water pH 4 compared with pH 9. Glufosinate efficacy was at least 10 and 17% greater for giant ragweed and Palmer amaranth control, respectively, with Carrier Water pH 4 compared with pH 9 in the greenhouse. In the greenhou...
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Influence of Carrier Water pH, Hardness, Foliar Fertilizer, and Ammonium Sulfate on Mesotrione Efficacy
Weed Technology, 2016Co-Authors: Pratap Devkota, Douglas J. Spaunhorst, William G JohnsonAbstract:Carrier Water pH, hardness, coapplied foliar fertilizer, Water conditioning agents, and plant height are critical considerations for optimum herbicide performance. Field studies were conducted to evaluate the effect of Carrier Water pH (4, 6.5, and 9) and zinc (Zn) or manganese (Mn) foliar fertilizer on mesotrione for horseweed and Palmer amaranth control. Additionally, effect of Carrier Water pH and foliar fertilizer was evaluated on 7.5-, 12.5-, and 17.5-cm tall horseweed. Greenhouse treatments consisted of Carrier Water pH and foliar fertilizer (Zn, Mn, or without fertilizer); or Water hardness (0 to 1,000 mg L−1) in the presence or absence of ammonium sulfate (AMS) for mesotrione control of giant ragweed, horseweed, and Palmer amaranth. Mesotrione activity was greater on horseweed with Carrier Water pH 6.5 compared to pH 4 or 9. Coapplied Zn fertilizer reduced mesotrione activity on Palmer amaranth in the field study in 2014 and horseweed in the greenhouse study. Mesotrione efficacy was greatly influe...
Arman Bonakdarpour - One of the best experts on this subject based on the ideXlab platform.
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Production of Hydrogen Peroxide for Drinking Water Treatment in a Proton Exchange Membrane Electrolyzer at Near-Neutral pH
Journal of The Electrochemical Society, 2020Co-Authors: Arman Bonakdarpour, Előd L Gyenge, David P WilkinsonAbstract:We provide a detailed report on the electrosynthesis of H2O2 for drinking Water treatment under near-neutral conditions using a proton exchange membrane (PEM) electrolyzer. Two novel cathode catalysts for O2 electroreduction to H2O2 were investigated in the PEM electrolyzer: an inorganic cobalt-carbon (Co–C) composite and an organic redox catalyst anthraquinone-riboflavinyl mixed with carbon (AQ–C), respectively. The impact of operational variables such as temperature, cathode Carrier Water flow rate, and anode configurations (aimed at mitigating carbon corrosion at the anode) were examined in single-pass and full recycle operation. Using a superficial current density of 245 mA cm−2 and an operating temperature of 40 °C, H2O2 molar fluxes of 360 μmol hr−1 cm−2 and 580 μmol hr−1 cm−2 were generated at near-neutral pH with the Co–C and RF-AQ catalysts, respectively. Seventy-two hour experiments with closed loop recirculation, produced H2O2 concentrations of 1300 and 3000 ppm for the Co–C and AQ–C catalysts, respectively. These concentrations are adequate for advanced oxidation (UV/H2O2) treatment of drinking Water, rendering the PEM electrolysis approach particularly suitable for on-site and on-demand production of H2O2.
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Design of bifunctional electrodes for co-generation of electrical power and hydrogen peroxide
Journal of Applied Electrochemistry, 2018Co-Authors: Arman Bonakdarpour, Előd L Gyenge, David P WilkinsonAbstract:We present a method of co-generating hydrogen peroxide and electrical power via the two-electron cathodic reduction of oxygen in a H_2/O_2 proton exchange membrane fuel cell (PEMFC). The cell uses a continuous flow of Carrier Water through its cathodic chamber to remove the hydrogen peroxide product at a neutral pH. To improve the co-generation of electric power and hydrogen peroxide, a number of different cathode configurations, using both four- and two-electron oxygen reducing electrocatalysts, were constructed and examined. With a bifunctional cathode structure consisting of side-by-side carbon-supported Pt– and Co–C-based catalyst layers, and a carbon-based micro-porous layer (MPL), a hydrogen peroxide generation flux of 8 µmol h^−1 cm^−2 is achieved. The corresponding power density is about 133 mW cm^−2. The co-generation of power and hydrogen peroxide could be used in a variety of applications, including the on-site production of hydrogen peroxide for Water treatment by advanced oxidation processes. Graphical Abstract
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Drinking Water Purification by Electrosynthesis of Hydrogen Peroxide in a Power‐Producing PEM Fuel Cell
Chemsuschem, 2013Co-Authors: Winton Li, Előd L Gyenge, Arman Bonakdarpour, David P WilkinsonAbstract:The industrial anthraquinone auto-oxidation process produces most of the world’s supply of hydrogen peroxide. For applications that require small amounts of H2O2 or have economically difficult transportation means, an alternate, on-site H2O2 production method is needed. Advanced drinking Water purification technologies use neutral-pH H2O2 in combination with UV treatment to reach the desired Water purity targets. To produce neutral H2O2 on-site and on-demand for drinking Water purification, the electroreduction of oxygen at the cathode of a proton exchange membrane (PEM) fuel cell operated in either electrolysis (power consuming) or fuel cell (power generating) mode could be a possible solution. The work presented here focuses on the H2/O2 fuel cell mode to produce H2O2. The fuel cell reactor is operated with a continuous flow of Carrier Water through the cathode to remove the product H2O2. The impact of the cobalt–carbon composite cathode catalyst loading, Teflon content in the cathode gas diffusion layer, and cathode Carrier Water flowrate on the production of H2O2 are examined. H2O2 production rates of up to 200 μmol h−1 cmgeometric −2 are achieved using a continuous flow of Carrier Water operating at 30 % current efficiency. Operation times of more than 24 h have shown consistent H2O2 and power production, with no degradation of the cobalt catalyst.
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Drinking Water purification by electrosynthesis of hydrogen peroxide in a power-producing PEM fuel cell.
ChemSusChem, 2013Co-Authors: Arman Bonakdarpour, Előd L Gyenge, David P WilkinsonAbstract:The industrial anthraquinone auto-oxidation process produces most of the world's supply of hydrogen peroxide. For applications that require small amounts of H2 O2 or have economically difficult transportation means, an alternate, on-site H2 O2 production method is needed. Advanced drinking Water purification technologies use neutral-pH H2 O2 in combination with UV treatment to reach the desired Water purity targets. To produce neutral H2 O2 on-site and on-demand for drinking Water purification, the electroreduction of oxygen at the cathode of a proton exchange membrane (PEM) fuel cell operated in either electrolysis (power consuming) or fuel cell (power generating) mode could be a possible solution. The work presented here focuses on the H2 /O2 fuel cell mode to produce H2 O2 . The fuel cell reactor is operated with a continuous flow of Carrier Water through the cathode to remove the product H2 O2 . The impact of the cobalt-carbon composite cathode catalyst loading, Teflon content in the cathode gas diffusion layer, and cathode Carrier Water flowrate on the production of H2 O2 are examined. H2 O2 production rates of up to 200 μmol h(-1) cmgeometric (-2) are achieved using a continuous flow of Carrier Water operating at 30 % current efficiency. Operation times of more than 24 h have shown consistent H2 O2 and power production, with no degradation of the cobalt catalyst.