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Geoff W. Stevens - One of the best experts on this subject based on the ideXlab platform.
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Screening Amino Acid Salts as Rate Promoters in Potassium Carbonate Solvent for Carbon Dioxide Absorption
Energy & Fuels, 2017Co-Authors: Guoping Hu, Kathryn H Smith, Yue Wu, Sandra E Kentish, Geoff W. StevensAbstract:Potassium Carbonate shows promise as a solvent for carbon capture due to its low cost and low environmental impact. However, improving the absorption kinetics of Potassium Carbonate solvent is crucial for reducing the capital cost of absorption equipment required to build the carbon dioxide capture plant. In this study, a series of amino acid salts were screened as reactants with carbon dioxide using the stopped flow technique. The amino acids investigated in this study were 2-piperazinecarboxylic acid, asparagine, aspartic acid, glycine, leucine, lysine, proline, sarcosine, serine, and valine. Furthermore, proline, sarcosine, glycine, leucine, and lysine were tested as rate promoters in Potassium Carbonate solvent for carbon dioxide absorption using a wetted wall column. Results showed that the amino group in the anions of the amino acid salt is the major species reacting with carbon dioxide. Therefore, the promoting effect of amino acid salts is sensitive to changes in pH values due to changes in specie...
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enzymatic carbon dioxide capture using a thermally stable carbonic anhydrase as a promoter in Potassium Carbonate solvents
Chemical Engineering Journal, 2017Co-Authors: Guoping Hu, Nagurny J. Nicholas, Kathryn H Smith, Sandra E Kentish, Joel Yong, Geoff W. StevensAbstract:Abstract Carbon capture and storage (CCS) is an effective way to reduce CO 2 emissions and to mitigate climate change effects. However, the cost of carbon capture has to be reduced to manageable levels before it can be deployed at an industrial scale. Potassium Carbonate solutions (K 2 CO 3 ) are good solvents for CO 2 capture because they have low regeneration energy, low degradation rates and low corrosivity. However, one shortcoming of K 2 CO 3 is that it has slow reaction kinetics with CO 2 . This limitation can be overcome by the addition of promoters to K 2 CO 3 solutions. In this study, the catalysis kinetics of a carbonic anhydrase (NZCA) promoter was tested via the stopped flow technique and a wetted wall column (WWC). The Michaelis-Menten catalysis parameter (k cat /K m ) was determined to be 2.7 × 10 7 M −1 s −1 at 298 K, allowing the catalysis reaction activation energy of 51 ± 1 kJ/mol to be obtained at 298–328 K. The catalysis coefficient of the NZCA was determined to be 5.3 × 10 8 M −1 s −1 using a WWC in 30 wt% Potassium Carbonate solutions (pH ∼ 11–12) at 323 K. Furthermore, the NZCA maintained more than 70% of its initial catalysis efficiency after continuously running for 8 h in 30 wt% K 2 CO 3 solutions at pH of 10.6–10.8 and temperature of 323 K.
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understanding the vapour liquid equilibrium of co2 in mixed solutions of Potassium Carbonate and Potassium glycinate
International Journal of Greenhouse Gas Control, 2015Co-Authors: Kathryn A Mumford, Nagurny J. Nicholas, Yue Wu, Geoff W. StevensAbstract:Abstract A thermodynamic model was developed to describe the absorption of CO 2 into a glycine promoted Potassium Carbonate solution. It was found that the model could effectively predict vapour–liquid equilibrium of CO 2 and solubility of hydrated Potassium Carbonate and Potassium biCarbonate in glycine promoted K 2 CO 3 solutions over a range of temperatures. Both simulation and experimental results showed CO 2 partial pressure decreased with the addition of glycine, indicating a good potential to improve CO 2 absorption efficiency in Potassium Carbonate solution.
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carbonic anhydrase promoted absorption of co2 into Potassium Carbonate solutions
Greenhouse Gases-Science and Technology, 2015Co-Authors: Hendy Thee, Kathryn H Smith, Gabriel Da Silva, Sandra E Kentish, Geoff W. StevensAbstract:The effect of adding relatively small quantities of Novozymes NS81239 (NCA) carbonic anhydrase enzyme on the absorption of CO 2 into a 30 wt% Potassium Carbonate solution has been investigated. Results demonstrated that at 40°C the addition of 2 μM NCA enhances the pseudo‐first‐order rate coefficient and thus the overall absorption process of CO 2 into Potassium Carbonate solvents by around 30%. As the enzyme concentration is increased in the range of about 0 to 2 μM the enhancement increases according to a first order relationship, although further increasing the NCA concentration to 9 μM presented no greater catalytic effect than that from 2 μM. The rate coefficient for NCA catalyzed CO 2 hydration measured in 30 wt% K 2 CO 3 solution at 40°C in a wetted wall column is similar to that measured in dilute, neutral pH media at room temperature using stopped flow spectrophotometry. This work also demonstrates that, at a constant enzyme concentration, the overall absorption of CO 2 into Carbonate solvents increases with temperature from 40°C to 60°C, whereas above this range an increase in temperature proves to be counter‐productive.
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a kinetic and process modeling study of co2 capture with mea promoted Potassium Carbonate solutions
Chemical Engineering Journal, 2012Co-Authors: Hendy Thee, Kathryn H Smith, Gabriel Da Silva, Sandra E Kentish, Kathryn A Mumford, Yohanes A Suryaputradinata, Geoff W. StevensAbstract:Abstract Aqueous solutions of Carbonate salts such as Potassium Carbonate (K 2 CO 3 ) have gained widespread acceptance as viable solvents for pre and post combustion capture of carbon dioxide (CO 2 ). However, due to poor reaction kinetics a rate promoter is considered essential to improve the rate of CO 2 absorption and hydration to biCarbonate. Using a well characterized wetted-wall column, we have evaluated the reaction kinetics of CO 2 absorption into a K 2 CO 3 solution promoted with monoethanolamine (MEA) under conditions resembling those found at industrial CO 2 capture plants. Results presented here show that at 63 °C the addition of MEA in small quantities, 1.1 M (5 wt.%) and 2.2 M (10 wt.%), accelerates the overall rate of absorption of CO 2 in a 30 wt.% Potassium Carbonate solvent by a factor of 16 and 45 respectively. The Arrhenius expression for the reaction between CO 2 and MEA is k MEA (M −1 s −1 ) = 4.24 × 10 9 exp(−3825/ T [K]) where the activation energy is 31.8 kJ mol −1 . Incorporating our experimental results into Aspen Plus™, we have developed an E-NRTL model that can replicate pilot plant and simulate industrial capture processes employing K 2 CO 3 promoted with MEA as the capture agent.
Sandra E Kentish - One of the best experts on this subject based on the ideXlab platform.
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recent progress on the performance of different rate promoters in Potassium Carbonate solvents for co2 capture
Energy Procedia, 2017Co-Authors: Guoping Hu, Kathryn H Smith, Yue Wu, Sandra E Kentish, Geoff W StevensAbstract:Abstract Over recent years our research group has examined the performance of a range of rate promoters in Potassium Carbonate solvent for carbon dioxide absorption. Promoters including boric acid, Potassium glycinate, Potassium prolinate, Potassium sarcosinate and a thermally stable carbonic anhydrase enzyme have been studied either with the stopped flow technique, a wetted wall column or in the pilot plant located at The University of Melbourne in Australia. The carbonic anhydrase enzyme was shown to have the best promotion performance. However, improvements are required in further improving thermal stability and recycling options in order for the enzyme to be applied in industrial solvent absorption processes. Amino acid salts including Potassium sarcosinate, prolinate and glycinate were proven to have high promotion performance at bench scale. Pilot plant results showed that the promotion performance of boric acid was poor, while Potassium glycinate was a good rate promoter with an increase in absorption rate of up to 5–6 times when adding 10 wt. % glycinate into 40–45 wt. % Potassium Carbonate solvent.
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Screening Amino Acid Salts as Rate Promoters in Potassium Carbonate Solvent for Carbon Dioxide Absorption
Energy & Fuels, 2017Co-Authors: Guoping Hu, Kathryn H Smith, Yue Wu, Sandra E Kentish, Geoff W. StevensAbstract:Potassium Carbonate shows promise as a solvent for carbon capture due to its low cost and low environmental impact. However, improving the absorption kinetics of Potassium Carbonate solvent is crucial for reducing the capital cost of absorption equipment required to build the carbon dioxide capture plant. In this study, a series of amino acid salts were screened as reactants with carbon dioxide using the stopped flow technique. The amino acids investigated in this study were 2-piperazinecarboxylic acid, asparagine, aspartic acid, glycine, leucine, lysine, proline, sarcosine, serine, and valine. Furthermore, proline, sarcosine, glycine, leucine, and lysine were tested as rate promoters in Potassium Carbonate solvent for carbon dioxide absorption using a wetted wall column. Results showed that the amino group in the anions of the amino acid salt is the major species reacting with carbon dioxide. Therefore, the promoting effect of amino acid salts is sensitive to changes in pH values due to changes in specie...
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enzymatic carbon dioxide capture using a thermally stable carbonic anhydrase as a promoter in Potassium Carbonate solvents
Chemical Engineering Journal, 2017Co-Authors: Guoping Hu, Nagurny J. Nicholas, Kathryn H Smith, Sandra E Kentish, Joel Yong, Geoff W. StevensAbstract:Abstract Carbon capture and storage (CCS) is an effective way to reduce CO 2 emissions and to mitigate climate change effects. However, the cost of carbon capture has to be reduced to manageable levels before it can be deployed at an industrial scale. Potassium Carbonate solutions (K 2 CO 3 ) are good solvents for CO 2 capture because they have low regeneration energy, low degradation rates and low corrosivity. However, one shortcoming of K 2 CO 3 is that it has slow reaction kinetics with CO 2 . This limitation can be overcome by the addition of promoters to K 2 CO 3 solutions. In this study, the catalysis kinetics of a carbonic anhydrase (NZCA) promoter was tested via the stopped flow technique and a wetted wall column (WWC). The Michaelis-Menten catalysis parameter (k cat /K m ) was determined to be 2.7 × 10 7 M −1 s −1 at 298 K, allowing the catalysis reaction activation energy of 51 ± 1 kJ/mol to be obtained at 298–328 K. The catalysis coefficient of the NZCA was determined to be 5.3 × 10 8 M −1 s −1 using a WWC in 30 wt% Potassium Carbonate solutions (pH ∼ 11–12) at 323 K. Furthermore, the NZCA maintained more than 70% of its initial catalysis efficiency after continuously running for 8 h in 30 wt% K 2 CO 3 solutions at pH of 10.6–10.8 and temperature of 323 K.
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carbon dioxide absorption into promoted Potassium Carbonate solutions a review
International Journal of Greenhouse Gas Control, 2016Co-Authors: Nagurny J. Nicholas, Kathryn H Smith, Sandra E Kentish, Guoping Hu, Kathryn A MumfordAbstract:Abstract The emission of carbon dioxide into the atmosphere is recognized as a significant driver for climate change. Carbon capture and storage (CCS) techniques are efficient and effective ways to reduce these emissions to the atmosphere. However, the cost of any carbon capture technique has to be reduced to manageable levels before it can be deployed at an industrial scale. Several methods for capturing carbon dioxide, such as absorption, adsorption, membrane techniques and cryogenic separation have been proposed, of which absorption is the closest to commercial reality. Potassium Carbonate is a good solvent for carbon dioxide capture because of its low regeneration energy, low degradation rates and low corrosivity. However, one shortcoming of Potassium Carbonate in CO2 absorption is that it has relatively slow reaction kinetics with CO2 resulting in the need for large absorption equipment. The most efficient method for improving the absorption kinetics is to add promoters into the Potassium Carbonate solutions. There have been a number of promoters studied over the last decades, including inorganic promoters such as arsenate, boric acid and vanadate, organic promoters such as different amines and amino acids, enzymatic promoters such as carbonic anhydrase and metal compounds mimicking carbonic anhydrase. In this paper, different promoters for CO2 absorption in Potassium Carbonate solutions are reviewed and their performance summarized. Additionally, a CO2 hydration promoting mechanism of deprotonation, followed by intermediate formation and then promoter regeneration is presented.
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carbonic anhydrase promoted absorption of co2 into Potassium Carbonate solutions
Greenhouse Gases-Science and Technology, 2015Co-Authors: Hendy Thee, Kathryn H Smith, Gabriel Da Silva, Sandra E Kentish, Geoff W. StevensAbstract:The effect of adding relatively small quantities of Novozymes NS81239 (NCA) carbonic anhydrase enzyme on the absorption of CO 2 into a 30 wt% Potassium Carbonate solution has been investigated. Results demonstrated that at 40°C the addition of 2 μM NCA enhances the pseudo‐first‐order rate coefficient and thus the overall absorption process of CO 2 into Potassium Carbonate solvents by around 30%. As the enzyme concentration is increased in the range of about 0 to 2 μM the enhancement increases according to a first order relationship, although further increasing the NCA concentration to 9 μM presented no greater catalytic effect than that from 2 μM. The rate coefficient for NCA catalyzed CO 2 hydration measured in 30 wt% K 2 CO 3 solution at 40°C in a wetted wall column is similar to that measured in dilute, neutral pH media at room temperature using stopped flow spectrophotometry. This work also demonstrates that, at a constant enzyme concentration, the overall absorption of CO 2 into Carbonate solvents increases with temperature from 40°C to 60°C, whereas above this range an increase in temperature proves to be counter‐productive.
Kathryn H Smith - One of the best experts on this subject based on the ideXlab platform.
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recent progress on the performance of different rate promoters in Potassium Carbonate solvents for co2 capture
Energy Procedia, 2017Co-Authors: Guoping Hu, Kathryn H Smith, Yue Wu, Sandra E Kentish, Geoff W StevensAbstract:Abstract Over recent years our research group has examined the performance of a range of rate promoters in Potassium Carbonate solvent for carbon dioxide absorption. Promoters including boric acid, Potassium glycinate, Potassium prolinate, Potassium sarcosinate and a thermally stable carbonic anhydrase enzyme have been studied either with the stopped flow technique, a wetted wall column or in the pilot plant located at The University of Melbourne in Australia. The carbonic anhydrase enzyme was shown to have the best promotion performance. However, improvements are required in further improving thermal stability and recycling options in order for the enzyme to be applied in industrial solvent absorption processes. Amino acid salts including Potassium sarcosinate, prolinate and glycinate were proven to have high promotion performance at bench scale. Pilot plant results showed that the promotion performance of boric acid was poor, while Potassium glycinate was a good rate promoter with an increase in absorption rate of up to 5–6 times when adding 10 wt. % glycinate into 40–45 wt. % Potassium Carbonate solvent.
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precipitating characteristics of Potassium biCarbonate using concentrated Potassium Carbonate solvent for carbon dioxide capture part 1 nucleation
Industrial & Engineering Chemistry Research, 2017Co-Authors: Yue Wu, Nouman R Mirza, Kathryn H Smith, Geoffery W. Stevens, Guoping Hu, Kathryn A MumfordAbstract:Potassium Carbonate is considered a promising solvent for carbon dioxide (CO2) capture as it is cost-effective and environmentally benign when compared to traditional amine-based solvents. In order to increase absorption capacity, the use of concentrated Potassium Carbonate solvent has been proposed in which CO2 absorption results in precipitation of biCarbonate. Understanding the formation of the solids in that system is important if this is to be used for CO2 capture. In this work, the precipitation behavior in the ternary system of Potassium Carbonate–Potassium biCarbonate–water was studied in a batch cooling crystallizer equipped with Focused Beam Reflectance Measurement (FBRM) and an Optimax workstation. The solubility data were validated using a regressed Electrolyte Non-Random Two Liquid (ENRTL) activity model developed in Aspen Plus. The precipitate was determined as kalicinite with hexagonal prism shape by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The nucleation kinetics wer...
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Screening Amino Acid Salts as Rate Promoters in Potassium Carbonate Solvent for Carbon Dioxide Absorption
Energy & Fuels, 2017Co-Authors: Guoping Hu, Kathryn H Smith, Yue Wu, Sandra E Kentish, Geoff W. StevensAbstract:Potassium Carbonate shows promise as a solvent for carbon capture due to its low cost and low environmental impact. However, improving the absorption kinetics of Potassium Carbonate solvent is crucial for reducing the capital cost of absorption equipment required to build the carbon dioxide capture plant. In this study, a series of amino acid salts were screened as reactants with carbon dioxide using the stopped flow technique. The amino acids investigated in this study were 2-piperazinecarboxylic acid, asparagine, aspartic acid, glycine, leucine, lysine, proline, sarcosine, serine, and valine. Furthermore, proline, sarcosine, glycine, leucine, and lysine were tested as rate promoters in Potassium Carbonate solvent for carbon dioxide absorption using a wetted wall column. Results showed that the amino group in the anions of the amino acid salt is the major species reacting with carbon dioxide. Therefore, the promoting effect of amino acid salts is sensitive to changes in pH values due to changes in specie...
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enzymatic carbon dioxide capture using a thermally stable carbonic anhydrase as a promoter in Potassium Carbonate solvents
Chemical Engineering Journal, 2017Co-Authors: Guoping Hu, Nagurny J. Nicholas, Kathryn H Smith, Sandra E Kentish, Joel Yong, Geoff W. StevensAbstract:Abstract Carbon capture and storage (CCS) is an effective way to reduce CO 2 emissions and to mitigate climate change effects. However, the cost of carbon capture has to be reduced to manageable levels before it can be deployed at an industrial scale. Potassium Carbonate solutions (K 2 CO 3 ) are good solvents for CO 2 capture because they have low regeneration energy, low degradation rates and low corrosivity. However, one shortcoming of K 2 CO 3 is that it has slow reaction kinetics with CO 2 . This limitation can be overcome by the addition of promoters to K 2 CO 3 solutions. In this study, the catalysis kinetics of a carbonic anhydrase (NZCA) promoter was tested via the stopped flow technique and a wetted wall column (WWC). The Michaelis-Menten catalysis parameter (k cat /K m ) was determined to be 2.7 × 10 7 M −1 s −1 at 298 K, allowing the catalysis reaction activation energy of 51 ± 1 kJ/mol to be obtained at 298–328 K. The catalysis coefficient of the NZCA was determined to be 5.3 × 10 8 M −1 s −1 using a WWC in 30 wt% Potassium Carbonate solutions (pH ∼ 11–12) at 323 K. Furthermore, the NZCA maintained more than 70% of its initial catalysis efficiency after continuously running for 8 h in 30 wt% K 2 CO 3 solutions at pH of 10.6–10.8 and temperature of 323 K.
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carbon dioxide absorption into promoted Potassium Carbonate solutions a review
International Journal of Greenhouse Gas Control, 2016Co-Authors: Nagurny J. Nicholas, Kathryn H Smith, Sandra E Kentish, Guoping Hu, Kathryn A MumfordAbstract:Abstract The emission of carbon dioxide into the atmosphere is recognized as a significant driver for climate change. Carbon capture and storage (CCS) techniques are efficient and effective ways to reduce these emissions to the atmosphere. However, the cost of any carbon capture technique has to be reduced to manageable levels before it can be deployed at an industrial scale. Several methods for capturing carbon dioxide, such as absorption, adsorption, membrane techniques and cryogenic separation have been proposed, of which absorption is the closest to commercial reality. Potassium Carbonate is a good solvent for carbon dioxide capture because of its low regeneration energy, low degradation rates and low corrosivity. However, one shortcoming of Potassium Carbonate in CO2 absorption is that it has relatively slow reaction kinetics with CO2 resulting in the need for large absorption equipment. The most efficient method for improving the absorption kinetics is to add promoters into the Potassium Carbonate solutions. There have been a number of promoters studied over the last decades, including inorganic promoters such as arsenate, boric acid and vanadate, organic promoters such as different amines and amino acids, enzymatic promoters such as carbonic anhydrase and metal compounds mimicking carbonic anhydrase. In this paper, different promoters for CO2 absorption in Potassium Carbonate solutions are reviewed and their performance summarized. Additionally, a CO2 hydration promoting mechanism of deprotonation, followed by intermediate formation and then promoter regeneration is presented.
Kathryn A Mumford - One of the best experts on this subject based on the ideXlab platform.
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precipitating characteristics of Potassium biCarbonate using concentrated Potassium Carbonate solvent for carbon dioxide capture part 1 nucleation
Industrial & Engineering Chemistry Research, 2017Co-Authors: Yue Wu, Nouman R Mirza, Kathryn H Smith, Geoffery W. Stevens, Guoping Hu, Kathryn A MumfordAbstract:Potassium Carbonate is considered a promising solvent for carbon dioxide (CO2) capture as it is cost-effective and environmentally benign when compared to traditional amine-based solvents. In order to increase absorption capacity, the use of concentrated Potassium Carbonate solvent has been proposed in which CO2 absorption results in precipitation of biCarbonate. Understanding the formation of the solids in that system is important if this is to be used for CO2 capture. In this work, the precipitation behavior in the ternary system of Potassium Carbonate–Potassium biCarbonate–water was studied in a batch cooling crystallizer equipped with Focused Beam Reflectance Measurement (FBRM) and an Optimax workstation. The solubility data were validated using a regressed Electrolyte Non-Random Two Liquid (ENRTL) activity model developed in Aspen Plus. The precipitate was determined as kalicinite with hexagonal prism shape by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The nucleation kinetics wer...
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carbon dioxide absorption into promoted Potassium Carbonate solutions a review
International Journal of Greenhouse Gas Control, 2016Co-Authors: Nagurny J. Nicholas, Kathryn H Smith, Sandra E Kentish, Guoping Hu, Kathryn A MumfordAbstract:Abstract The emission of carbon dioxide into the atmosphere is recognized as a significant driver for climate change. Carbon capture and storage (CCS) techniques are efficient and effective ways to reduce these emissions to the atmosphere. However, the cost of any carbon capture technique has to be reduced to manageable levels before it can be deployed at an industrial scale. Several methods for capturing carbon dioxide, such as absorption, adsorption, membrane techniques and cryogenic separation have been proposed, of which absorption is the closest to commercial reality. Potassium Carbonate is a good solvent for carbon dioxide capture because of its low regeneration energy, low degradation rates and low corrosivity. However, one shortcoming of Potassium Carbonate in CO2 absorption is that it has relatively slow reaction kinetics with CO2 resulting in the need for large absorption equipment. The most efficient method for improving the absorption kinetics is to add promoters into the Potassium Carbonate solutions. There have been a number of promoters studied over the last decades, including inorganic promoters such as arsenate, boric acid and vanadate, organic promoters such as different amines and amino acids, enzymatic promoters such as carbonic anhydrase and metal compounds mimicking carbonic anhydrase. In this paper, different promoters for CO2 absorption in Potassium Carbonate solutions are reviewed and their performance summarized. Additionally, a CO2 hydration promoting mechanism of deprotonation, followed by intermediate formation and then promoter regeneration is presented.
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understanding the vapour liquid equilibrium of co2 in mixed solutions of Potassium Carbonate and Potassium glycinate
International Journal of Greenhouse Gas Control, 2015Co-Authors: Kathryn A Mumford, Nagurny J. Nicholas, Yue Wu, Geoff W. StevensAbstract:Abstract A thermodynamic model was developed to describe the absorption of CO 2 into a glycine promoted Potassium Carbonate solution. It was found that the model could effectively predict vapour–liquid equilibrium of CO 2 and solubility of hydrated Potassium Carbonate and Potassium biCarbonate in glycine promoted K 2 CO 3 solutions over a range of temperatures. Both simulation and experimental results showed CO 2 partial pressure decreased with the addition of glycine, indicating a good potential to improve CO 2 absorption efficiency in Potassium Carbonate solution.
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understanding the vapour liquid equilibrium of co2 in mixed solutions of Potassium Carbonate and Potassium glycinate
International Journal of Greenhouse Gas Control, 2015Co-Authors: Andrew Lee, Kathryn A Mumford, Nathan Johann Nicholas, Geoff W StevensAbstract:Abstract The vapour–liquid equilibrium of CO2 above a solution of Potassium Carbonate and Potassium glycinate was studied in a dynamic equilibrium apparatus, with a stationary liquid phase and moving gas phase. The partial pressure of CO2 and liquid phase speciation was measured for solutions containing 4.82 mol Potassium Carbonate/kg water and 0.64, 1.36, 2.16 and 3.06 mol Potassium glycinate/kg water across a range of loadings at temperatures of 50 °C, 60 °C and 70 °C. It was found that the partial pressure of CO2 decreased significantly as the concentration of Potassium glycinate increased, indicating that the Potassium glycinate was acting as an additional mode of CO2 capture within the solution. This was supported by significant amounts of glycine carbamate observed in the solutions. The partial pressure of CO2 was found to increase with increasing temperature whilst the amount of glycine carbamate decreased, indicating that the solvent can be thermally regenerated.
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demonstration of a concentrated Potassium Carbonate process for co2 capture
Energy & Fuels, 2014Co-Authors: Kathryn H Smith, Dimple Quyn, Jeffri Gouw, Indrawan Indrawan, Navin Thanumurthy, Robyn Cuthbertson, Gongkui Xiao, Aravind V Rayer, Kathryn A Mumford, Nagurny J. NicholasAbstract:A precipitating Potassium Carbonate (K2CO3)-based solvent absorption process has been developed by the Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC) for capturing carbon dioxide (CO2) from industrial sources, such as power plant flue gases. Demonstration of this process is underway using both a laboratory-based pilot plant located at The University of Melbourne and an industrial pilot plant located at the Hazelwood Power Station in Victoria, Australia. The laboratory-scale pilot plant has been designed to capture 4–10 kg/h CO2 from an air/CO2 feed gas rate of 30–55 kg/h. The power-station-based pilot plant has been designed to capture up to 1 tonne/day CO2 from the flue gas of a brown-coal-fired power station. In this paper, results from trials using concentrated Potassium Carbonate (20–40 wt %) solvent are presented for both pilot plants. Performance data (including pressure drop, holdup, solvent loadings, temperature profile, and CO2 removal efficiency) have been collected from ea...
Geoff W Stevens - One of the best experts on this subject based on the ideXlab platform.
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recent progress on the performance of different rate promoters in Potassium Carbonate solvents for co2 capture
Energy Procedia, 2017Co-Authors: Guoping Hu, Kathryn H Smith, Yue Wu, Sandra E Kentish, Geoff W StevensAbstract:Abstract Over recent years our research group has examined the performance of a range of rate promoters in Potassium Carbonate solvent for carbon dioxide absorption. Promoters including boric acid, Potassium glycinate, Potassium prolinate, Potassium sarcosinate and a thermally stable carbonic anhydrase enzyme have been studied either with the stopped flow technique, a wetted wall column or in the pilot plant located at The University of Melbourne in Australia. The carbonic anhydrase enzyme was shown to have the best promotion performance. However, improvements are required in further improving thermal stability and recycling options in order for the enzyme to be applied in industrial solvent absorption processes. Amino acid salts including Potassium sarcosinate, prolinate and glycinate were proven to have high promotion performance at bench scale. Pilot plant results showed that the promotion performance of boric acid was poor, while Potassium glycinate was a good rate promoter with an increase in absorption rate of up to 5–6 times when adding 10 wt. % glycinate into 40–45 wt. % Potassium Carbonate solvent.
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understanding the vapour liquid equilibrium of co2 in mixed solutions of Potassium Carbonate and Potassium glycinate
International Journal of Greenhouse Gas Control, 2015Co-Authors: Andrew Lee, Kathryn A Mumford, Nathan Johann Nicholas, Geoff W StevensAbstract:Abstract The vapour–liquid equilibrium of CO2 above a solution of Potassium Carbonate and Potassium glycinate was studied in a dynamic equilibrium apparatus, with a stationary liquid phase and moving gas phase. The partial pressure of CO2 and liquid phase speciation was measured for solutions containing 4.82 mol Potassium Carbonate/kg water and 0.64, 1.36, 2.16 and 3.06 mol Potassium glycinate/kg water across a range of loadings at temperatures of 50 °C, 60 °C and 70 °C. It was found that the partial pressure of CO2 decreased significantly as the concentration of Potassium glycinate increased, indicating that the Potassium glycinate was acting as an additional mode of CO2 capture within the solution. This was supported by significant amounts of glycine carbamate observed in the solutions. The partial pressure of CO2 was found to increase with increasing temperature whilst the amount of glycine carbamate decreased, indicating that the solvent can be thermally regenerated.
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pre combustion capture of co2 results from solvent absorption pilot plant trials using 30 wt Potassium Carbonate and boric acid promoted Potassium Carbonate solvent
International Journal of Greenhouse Gas Control, 2012Co-Authors: Kathryn H Smith, Kohei Endo, Abdul Qader, Clare Anderson, Barry Hooper, Sandra E Kentish, Kathryn A Mumford, Geoff W StevensAbstract:Abstract Pre-combustion capture of carbon dioxide (CO2) from synthesis gas has been demonstrated using a solvent absorption pilot plant. The plant was designed to capture 30–50 kg/h (∼1 tonne/day) of CO2 from 300 kg/h of syngas. The solvent used in these trials was a Potassium Carbonate (K2CO3) solution. Potassium Carbonate shows promise as a solvent for CO2 capture because it requires lower energy for regeneration and has a low environmental impact when compared with the traditional amine-based solvents. However, the rate of CO2 absorption in K2CO3 is slow and as such there have been several studies evaluating rate promoters for this process. Boric acid has been identified as one such promoter. The pilot plant in this study was successfully operated on a campaign basis for 16 days using both an un-promoted 30 wt% K2CO3 solution as well as a 30 wt% K2CO3 solution promoted with 3 wt% boric acid. There was no net improvement in the absorption of CO2 observed in the presence of boric acid. This result is attributed to the boric acid having reduced the pH and therefore OH− concentration of the system, which in turn reduced the rate of the controlling kinetic reaction to form Potassium biCarbonate (KHCO3) from CO2. Changes in the solvent physical properties, due to interaction with syngas impurities, were found to influence the hydrodynamic performance of the packed columns. BiCarbonate precipitation and vessel level control issues also led to operational difficulties. ASPEN Plus™ simulations have been developed to predict the performance of the plant. In general the model predicts the performance of the plant well (to within ±5%) and will be important for future process development, design and optimisation.
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pre combustion capture of co2 results from solvent absorption pilot plant trials using 30wt Potassium Carbonate and boric acid promoted Potassium Carbonate solvent
International Journal of Greenhouse Gas Control, 2012Co-Authors: Kathryn H Smith, Kohei Endo, Abdul Qader, Clare Anderson, Barry Hooper, Sandra E Kentish, Kathryn A Mumford, Wendy Tao, Geoff W StevensAbstract:Abstract Pre-combustion capture of carbon dioxide (CO2) from synthesis gas has been demonstrated using a solvent absorption pilot plant. The plant was designed to capture 30–50 kg/h (∼1 tonne/day) of CO2 from 300 kg/h of syngas. The solvent used in these trials was a Potassium Carbonate (K2CO3) solution. Potassium Carbonate shows promise as a solvent for CO2 capture because it requires lower energy for regeneration and has a low environmental impact when compared with the traditional amine-based solvents. However, the rate of CO2 absorption in K2CO3 is slow and as such there have been several studies evaluating rate promoters for this process. Boric acid has been identified as one such promoter. The pilot plant in this study was successfully operated on a campaign basis for 16 days using both an un-promoted 30 wt% K2CO3 solution as well as a 30 wt% K2CO3 solution promoted with 3 wt% boric acid. There was no net improvement in the absorption of CO2 observed in the presence of boric acid. This result is attributed to the boric acid having reduced the pH and therefore OH− concentration of the system, which in turn reduced the rate of the controlling kinetic reaction to form Potassium biCarbonate (KHCO3) from CO2. Changes in the solvent physical properties, due to interaction with syngas impurities, were found to influence the hydrodynamic performance of the packed columns. BiCarbonate precipitation and vessel level control issues also led to operational difficulties. ASPEN Plus™ simulations have been developed to predict the performance of the plant. In general the model predicts the performance of the plant well (to within ±5%) and will be important for future process development, design and optimisation.
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the solubility of sulfur dioxide and carbon dioxide in an aqueous solution of Potassium Carbonate
International Journal of Greenhouse Gas Control, 2011Co-Authors: David Wappel, Kathryn H Smith, Sandra E Kentish, Sebastian Joswig, Ash Khan, David C Shallcross, Geoff W StevensAbstract:Abstract This study investigates the effect of sulfur dioxide (SO2) on the removal of carbon dioxide (CO2) from a typical power station flue gas stream using an aqueous Potassium Carbonate (K2CO3) solvent. The influence of SO2 on the solubility of CO2 into a 30 wt% K2CO3 solution was measured using a dynamic vapour–liquid equilibrium apparatus at temperatures of 90 °C and 100 °C. The study was conducted at various loadings (moles CO2 absorbed/moles K2CO3) at atmospheric pressure using N2 as the carrier gas. It was found that SO2 preferentially reacts with K2CO3, displacing an equivalent molal quantity of CO2 into the vapor phase. An experimental analysis of the absorbed SO2 in the K2CO3 solution showed that sulfite was the major species present. Further analysis showed that the absorption of SO2 into K2CO3 solutions is a non-reversible reaction at 100 °C and hence sulfur would accumulate in the solvent and consequently over time reduce the capacity of the solvent to absorb CO2.