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Parampaul K Banipal - One of the best experts on this subject based on the ideXlab platform.
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volumetric properties of some α ω aminocarboxylic acids in aqueous sodium Acetate and Magnesium Acetate solutions at t 288 15 to 318 15 k
Journal of Chemical & Engineering Data, 2010Co-Authors: Tarlok S Banipal, Gagandeep K Kahlon, Jasbir Kaur, Kultar Singh, Vishu Mehra, Raghav Chawla, Parampaul K BanipalAbstract:Densities, ρ, of glycine (GLY), 4-aminobutyric acid (4-ABA), and 6-aminocaproic acid (6-ACA) in water and in aqueous solutions of sodium Acetate (SA) and Magnesium Acetate (MA) having a molality of (0.10, 0.25, 0.50 and 1.00) mol·kg−1 have been determined by using a vibrating-tube digital densimeter at T = (288.15 to 318.15) K. These data have been used to calculate the apparent molar volumes, Vϕ, of the studied α,ω-aminocarboxylic acids. The partial molar volumes, V2,m0, at infinite dilution are evaluated and further used to obtain the corresponding transfer volumes, ΔtrV2,m0, for α,ω-aminocarboxylic acids from water to aqueous SA and MA solutions. Partial molar expansibilities, VE0, of α,ω-aminocarboxylic acids and interaction coefficients have been calculated. The ΔtrV2,m0 values for the α,ω-aminocarboxylic acids are positive, and these values increase with an increase in the concentration of SA and MA as well as with temperature. The results obtained have been rationalized in terms of various interact...
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interactions of some peptides with sodium Acetate and Magnesium Acetate in aqueous solutions at 298 15 k a volumetric approach
Journal of Molecular Liquids, 2008Co-Authors: Tarlok S Banipal, Damanjit Kaur, Parampaul K Banipal, Gagandeep SinghAbstract:Abstract The apparent molar volumes, Vϕ of diglycine, triglycine and glycyl- l -leucine have been determined in water and in aqueous sodium Acetate (0.5, 1.0, 2.0, and 4.0 mB) and Magnesium Acetate (0.5, 1.0, 1.5, and 2.0 mB) solutions at 298.15 K by the measurement of densities using vibrating-tube digital densimeter. The partial molar volumes, V2,m0 obtained from Vϕ have been used to calculate the partial molar volumes of transfer, ΔtrV2,m0 for these peptides from water to aqueous solutions of sodium Acetate (SA) and Magnesium Acetate (MA) solutions. The hydration numbers, nH and volumetric interaction coefficients have also been calculated. The ΔtrV2,m0 data suggest that ion-charged/or peptide group interactions of peptides are stronger with MA in comparison to SA.
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thermodynamic and transport properties of l serine and l threonine in aqueous sodium Acetate and Magnesium Acetate solutions at t 298 15 k
The Journal of Chemical Thermodynamics, 2007Co-Authors: Tarlok S Banipal, Damanjit Kaur, Parampaul K Banipal, Gagandeep SinghAbstract:Abstract The apparent molar volumes, V2,ϕ, apparent molar adiabatic compressibilities, κS,2,ϕ, and relative viscosities, ηr, of l -serine and l -threonine in different concentrations of aqueous sodium Acetate and Magnesium Acetate solutions at T = 298.15 K have been obtained from the measurements of densities, speed of sound, and flow time, respectively. These data are used to derive the partial molar volumes, V 2 ∘ , partial molar adiabatic compressibilities, κ S , 2 ∘ (at infinite dilution), and viscosity B-coefficients. The corresponding quantities of transfer, (ΔtV0, Δ t κ S , 2 ∘ , and ΔtB), have been obtained. The activation free energy, Δ μ 2 ∘ ≠ , for viscous flow has been calculated for l -serine and l -threonine in aqueous solutions. The hydration numbers, nH, side chain contributions, and interaction coefficients have also been calculated. The values of V 2 ∘ , κ S , 2 ∘ , viscosity B-coefficient, and Δ μ 2 ∘ ≠ for viscous flow increase with the concentration of sodium Acetate and Magnesium Acetate solutions. The influence of Magnesium Acetate on the transfer properties is greater than sodium Acetate in aqueous solutions. A comparison of ΔtV0, Δ κ S , 2 ∘ , and ΔtB values for l -serine and l -threonine with the reported data for dl -α-alanine and dl -α-amino-n-butyric acid in aqueous sodium Acetate and Magnesium Acetate solutions shows that the values are greater for l -serine and l -threonine at the same concentration of sodium Acetate and Magnesium Acetate.
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effect of Magnesium Acetate on the volumetric and transport behavior of some amino acids in aqueous solutions at 298 15 k
The Journal of Chemical Thermodynamics, 2006Co-Authors: Tarlok S Banipal, Damanjit Kaur, Parampaul K BanipalAbstract:Abstract Densities, ρ , and viscosities, η , of glycine, dl -α-alanine, dl -α-amino- n -butyric acid, l -leucine and l -phenylalanine in 0.5, 1.0, 1.5 and 2.0 m B of aqueous Magnesium Acetate solutions at 298.15 K have been measured as a function of concentration of amino acids using vibrating tube-digital densimeter and Ubbelohde capillary type viscometer, respectively. The apparent molar volumes, V ϕ , and relative viscosities, η r , of amino acids have been derived. The partial molar volume at infinite dilution, V 2 0 , and viscosity B -coefficient obtained from these data have been used to calculate the corresponding transfer parameters, Δ t V 0 , and Δ t B , for the studied amino acids from water to aqueous Magnesium Acetate solutions. The activation free energies, Δ μ 2 0 ≠ , for the viscous flow of solutions have been obtained by application of the transition-state theory to the viscosity B -coefficient data. The interaction coefficients and hydration number, n H , of amino acids in aqueous solutions have also been calculated to see the effect of Magnesium Acetate on the hydration of amino acids. The contribution of the zwitterionic end groups ( NH 3 + , COO − ) and (CH 2 ) group of the amino acids to V 2 0 , viscosity B -coefficient and Δ μ 2 0 ≠ have been calculated. These results have been rationalized in terms of the hydration of hydrophilic and hydrophobic parts of amino acids.
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effect of sodium Acetate and Magnesium Acetate on the solution behavior of some amino acids in water at 298 15 k a compressibility approach
Zeitschrift für Physikalische Chemie, 2006Co-Authors: Tarlok S Banipal, Damanjit Kaur, Parampaul K BanipalAbstract:Apparent molar adiabatic compressibility, K 2,Φ,S , of glycine, DL-α-alanine, DL-α-amino-n-butyric acid, L-leucine and L-phenylalanine in water and in (0.5, 1.0, 2.0, 4.0, 5.5 mol kg -1 ) aqueous sodium Acetate and in (0.5, 1.0, 1.5, 2.0 mol kg -1 ) aqueous Magnesium Acetate solutions has been determined from sound velocity, u, measurements at 298.15 K. The partial molar adiabatic compressibilities at infinite dilution, K 0 2,S , obtained from K 2,Φ,S data have been used to calculate the corresponding partial molar adiabatic compressibilities of transfer at infinite dilution, Δ t K 0 2,S , from water to aqueous sodium Acetate and Magnesium Acetate (cosolutes) solutions. The Δ t K 0 2.S values are positive for the studied amino acids in case of both the cosolutes and the values increase with the increase of the concentrations of both the cosolutes. The trends of Δ t K 0 2.S have been rationalized in terms of the hydration of hydrophilic and hydrophobic parts of the amino acids studied. The interaction coefficients and hydration number, n H , have also been calculated and are discussed in terms of the dehydration effect of sodium Acetate and Magnesium Acetate upon the amino acids in solutions. Attempt has been made to correlate these results with the earlier reported volumetric and viscometric studies for the same systems.
Paul T Williams - One of the best experts on this subject based on the ideXlab platform.
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enhanced nox reduction with so2 capture under air staged conditions by calcium Magnesium Acetate in an oil fired tunnel furnace
Energy & Fuels, 2006Co-Authors: W Nimmo, A A Patsias, Paul T WilliamsAbstract:The technique of combustion modification by air staging (over-fire air) for the control of NOx emissions is currently implemented in many coal-fired power stations. This paper presents results from a new process involving the injection of calcium Magnesium Acetate (CMA), which can reduce SO2 and at the same time enhance NOx reductions above those achievable by air staging alone. The experiments were performed in a 3.5m long, horizontal tunnel furnace with an internal diameter of 500 mm operated at 80 kWth by firing gas-oil. The organic content of CMA behaves like a fuel, and the Ca content calcines principally to CaO for acid gas capture in the furnace at temperatures greater than 1000 °C. The solubility of CMA in water means that concentrated solutions can be sprayed into the furnace as a fine mist, giving the possibility of intimate mixing with combustion gases. The concentration of fuel nitrogen in the fuel could be easily modified by varying the amount of dopant (quinoline) injected into the oil feed ...
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new technology for control of nox so2 and hcl emissions from large scale combustion plant using calcium Magnesium Acetate
Journal of The Energy Institute, 2006Co-Authors: W Nimmo, A A Patsias, B M Gibbs, Paul T WilliamsAbstract:Abstract Calcium Magnesium Acetate (CMA) combines the essential properties for NOx control by reburning and in furnace acid gas capture by calcium in one reducing agent. The organic content behaves like a fuel in the reburn zone of a furnace and the Ca content calcines in the furnace principally to CaO for acid gas capture. The technique can be modified for advanced reburning by the addition of urea to the CMA solution so that the selective non-catalytic reduction (SNCR) agent enters the reburn zone at the point of CMA injection. The performance of this novel technique has been assessed for NOx, SO2 and HCl control at the pilot scale, in a combustor operating at 80 kW. Simultaneous reduction of all three pollutants was obtained and a synergy between SO2 and HCl capture was identified. Comparison of the performance of calcium Magnesium Acetate with a suite of five other carboxylic salts has been performed. NOx reduction has been correlated to volatile organic content and the decomposition rates of the carb...
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calcium based sorbents for simultaneous nox sox reduction in a down fired furnace
Fuel, 2005Co-Authors: A A Patsias, W Nimmo, B M Gibbs, Paul T WilliamsAbstract:Abstract The performance of a suite of different carboxylic salts of calcium, have been assessed as dual NO x /SO x reducing agents. The salts studied include, calcium Magnesium Acetate (CMA), calcium Acetate (CA), calcium formate (CF), calcium benzoate (CB), calcium propionate (CP) and Magnesium Acetate (MA). The primary fuel was propane operating with a primary zone stoichiometry fixed at λ 1 =1.05 and the reburn zone stoichiometry, λ 2 , was varied between 1.03 and 0.86. Overall stoichiometry, λ 3 , was 1.15. CMA was also tested using a US Blend coal as the primary fuel. Experiments were performed in a down-fired pulverised coal furnace operating at an output of 80 kWth. Results showed that CMA and CP were the best dual NO x /SO 2 performers followed by CB, CA, MA and CF. Also, the co-injection of urea with the carboxylic salts as an advanced reburning agent was studied. The results showed that real improvements in NO reduction over basic reburning of greater than 70% could be obtained depending to a large extent on the initial effectiveness of the reburn fuel as well as nitrogen stoichiometric ratio within the reburn zone. Decomposition of the carboxylic salts was studied by thermo-gravimetric analysis (TGA) yielding information on the release of organic fractions important as precursors for CH i radical formation. Examination of structural and thermo-chemical properties of the carboxylic salts identified a correlation of NO reduction under reburning conditions with volatile organic content. Calcium Magnesium Acetate and calcium propionate showed superior SO 2 capture ability with reductions greater than 70% at Ca/S above 2, around 20% higher than calcium Acetate and calcium formate. Magnesium Acetate achieved reductions of less than 10% at Mg/S ratios up to 2.5. There is a clear difference in the potential effectiveness of the sorbents as dual NO x /SO 2 reductants, since the organic input for a given Ca input varies according to the composition of the sorbent. Some compromise may have to be made when choosing the correct operating conditions since good reductions in SO 2 may not give acceptable NO x reductions. However, the application of advanced reburning under these conditions has been shown here to compensate for low initial NO x reductions by basic reburning.
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calcium Magnesium Acetate and urea advanced reburning for no control with simultaneous so2 reduction
Fuel, 2004Co-Authors: W Nimmo, A A Patsias, B M Gibbs, E Hampartsoumian, Michael Fairweather, Paul T WilliamsAbstract:Calcium Magnesium Acetate (CMA) shows potential as a reductant for simultaneous NOx and SOx removal from coal-fired combustion plant. The performance of urea co-injection with CMA on NO reduction in an ‘advanced reburn’ (AR) configuration has been investigated with a view to optimization of the process in a pulverized coal-fired furnace operating at 80 kW. The impact on SO2 reduction has also been investigated. Urea/CMA solution was sprayed into the reburn zone of the furnace using twin-fluid atomizers over a range of reductant/NO stoichiometric ratios (NSR). The influence on NO reductions of primary zone stoichiometry (λ1) was investigated for a range of CMA reburn feed rates (Rff) and reburn zone stoichiometry (λ2). In addition, the effect of temperature on the SNCR performance of urea was investigated. Optimum process conditions were categorized either by maximizing NO and SO2 reductions (Modes A and B, respectively) or maximizing reductant utilization efficiencies (Modes C and D). NO control was best performed at λ1=1.05, but SO2 reductions were greatest at more fuel-lean primary zone conditions (λ1=1.15). Highest NO reductions of 85% under AR-rich conditions were achieved under Mode A, but were only slightly higher compared with reductions of 79% under Mode B, where SO2 reductions were optimized at 85%. N-utilization was also at an acceptable level of 25% compared to the maximum utilization efficiency which was obtained at NSR=1.5 of 30% for the same conditions of stoichiometry operating in Mode C. Operation at this lower level of reburn (9.6%) could significantly reduce the consumption of CMA with some impact on NO reduction (73%). SO2 removal performance would be compromised severely with reductions lowered from 75% at Mode A to 35% at Mode C. Optimizing Ca utilization (Mode D) resulted in poor NO and SO2 reductions, at 61 and 22%, respectively, and can be discounted as a viable option. The technique offers flexibility of operation depending on the emission control requirements.
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simultaneous reduction of nox and so2 emissions from coal combustion by calcium Magnesium Acetate
Fuel, 2004Co-Authors: W Nimmo, A A Patsias, B M Gibbs, E Hampartsoumian, Paul T WilliamsAbstract:Abstract The potential of calcium Magnesium Acetate (CMA) as a medium for the simultaneous control of NO x and SO x emissions has been investigated using a pulverized coal combustion rig operating at 80 kW. A US and a UK coal of significantly different sulphur contents were used as primary fuel and CMA was injected in solution form into the combustion gases by horizontally opposed twin-fluid atomisers at temperatures of 1100–1200 °C. SO 2 reductions typically greater than 80 and 70% were found for initial SO 2 levels of 1000 and 1500 ppm, respectively, at Ca/S ratios greater than 2.5. There did not appear to be significant limitation on sulphation by pore blockage using CMA due to the open structure formed during calcination and there is clear potential for zero SO 2 emissions at higher Ca/S ratios. The Ca content of the CMA in the form of CaO, via a droplet drying/particle calcination process, absorbs SO 2 by sulphation processes by penetration into the open pore structure of these particles. The effect of primary zone stoichiometry ( λ 1 =1.05, 1.15 and 1.4) on NO x reduction was investigated for a range of CMA feed rates up to a coal equivalent of 24% of the total thermal input. NO x reductions of 80, 50 and 30% were achieved at a primary zone stoichiometry of λ 1 =1.05, 1.15 and 1.4, respectively, for a reburn zone residence time of 0.8 s. At lower equivalent reburn fuel fractions, coal gave greater NO x reductions than CMA but similar levels were achieved above Rff=18%. The mechanism for NO x reduction involves the organic fraction of CMA which pyrolyses into hydrocarbon fragments (CH i ), but to a lesser degree than coal, which may then react with NO x in a manner similar to a conventional ‘reburn’ mechanism where NO x is partly converted to N 2 depending on the availability of oxygen.
Feng Duan - One of the best experts on this subject based on the ideXlab platform.
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Utilization of an Organic Calcium Compound to Reduce SO2 and NO Emissions from Sewage Sludge Combustion
2018Co-Authors: Lihui Zhang, Feng Duan, Chiensong ChyangAbstract:To remove gas pollutant emissions from sewage sludge combustion, modified calcium Magnesium Acetate (MCMA) was used as an organic calcium compound (OCC) to blend with sludge. The main objective of this study was to determine the pollutant emission characteristics of sewage sludge and fuel blended with MCMA during combustion in a tube furnace. The effects of operating parameters on the mean SO2 and NO emissions and the reduction ratios of SO2 and NO were investigated. The results showed that MCMA simultaneously captured 69.9% of SO2 and 31.3% of NO at a temperature of 800 °C and a Ca/S molar ratio of 2.0. Furthermore, the Ca/S ratio and reaction temperature significantly impacted the mean SO2 emission and SO2 reduction ratio. The SO2 reduction ratio increased with increases of the Ca/S ratio and temperature. However, SO2 emission decreased with increasing Ca/S ratio but increased with increasing reaction temperature. In addition to the main effects corresponding to single factors, the interaction effect of air flow rate and Ca/S ratio was a dominant factor that affected the mean NO emission and NO reduction ratio
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performance study of modified calcium Magnesium Acetate mcma in the process of high temperature co2 capture and the application of spent mcma for sequential so2 removal
Asia-Pacific Journal of Chemical Engineering, 2017Co-Authors: Xiaoru Sun, Lihui Zhang, Feng Duan, Dongdong Fang, Yunlan SunAbstract:The modified calcium Magnesium Acetate (MCMA) has the similar characteristics and properties to those of CMA and a lower production cost. In this study, the effect of temperature on the performance of MCMA in the cyclic calcination/carbonation reaction (CCCR) process was investigated. The pore structure characteristics of the spent MCMA particles were also studied. A tubular furnace reactor was used to study the sulfation reaction characteristics and kinetic characteristics of the spent MCMA after CCCR. The microstructure and the constituent elements of the spent MCMA after sulfation reaction were analyzed by the scanning electron microscopy (SEM) and the energy dispersive X-ray spectrometry (EDS). The adsorption characteristics of MCMA were found similar to the analytically pure CMA in the CCCR process. The carbonation conversion of MCMA decreases significantly first and then varies little with increasing the cycle numbers. The sulfation process of all spent MCMA can be divided into two distinct stages including the chemical reaction-controlled stage and the product layer diffusion-controlled stage. The shrinking unreacted core model is appropriate to analyze the sulfation kinetic characteristics of the spent MCMA in the sulfation process. The sulfation conversions of the spent MCMA decrease gradually with increasing the cycle numbers of CCCR, while the MCMA-30 (the modified CMA cycled 30 times in the CCCR process) still shows a sulfation conversion of 35.48%, indicating that the spent MCMA can be used as an ideal desulfurizer before the fresh sorbent serving as a CO2 carrier in the CCCR process. © 2017 Curtin University of Technology and John Wiley & Sons, Ltd.
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comparison of thermal behavior for modified calcium Magnesium Acetate blended separately with peanut shell and sewage sludge at different atmospheres
Journal of Thermal Analysis and Calorimetry, 2017Co-Authors: Lihui Zhang, Feng Duan, Xiaoru Sun, Yaji HuangAbstract:Experiments were conducted in a thermogravimetric analyzer to evaluate and compare the thermal behavior for modified calcium Magnesium Acetate (MCMA) blended separately with peanut shell (PS) and sewage sludge (SS) at different atmospheres. Characteristic temperatures and indices of blended fuels of samples were also investigated. Results indicated that devolatilization indices of blended fuels decrease compared with separate samples because of higher decomposition temperature of MCMA. Comprehensive combustibility index of PS/MCMA-O30 increases at higher mole ratio of calcium to sulfur (Ca/S ratio), while its value of SS/MCMA-O30 increases first as Ca/S ratio increases from 0 to 2, and decreases little at Ca/S ratio of 3. Significant mass loss of blended fuels occurs in the second combustion stage. Combustion performances of PS and SS are enhanced after MCMA addition at higher oxygen ratio due to improved fixed carbon combustion. Characteristic temperatures decrease, while characteristic indices increase with oxygen ratio under O2/CO2 atmosphere.
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pore structure and fractal analysis for char of sludge blended with calcium Magnesium Acetate during pyrolysis process
Asia-Pacific Journal of Chemical Engineering, 2016Co-Authors: Lihui Zhang, Yaji Huang, Feng DuanAbstract:The changes in pore structure characteristics of sewage sludge blended with calcium Magnesium Acetate (CMA) during pyrolysis process were investigated. Sludge and its blended fuel with CMA were characterized by N2 isothermal absorption method, and the data were used to analyze the fractal properties of the obtained samples. Results show that pyrolysis temperature has notable impact on the pore structure and morphology of both samples. The Brunauer–Emmett–Teller (BET) specific surface area (SBET) of both samples increases greatly as the temperature increases from 400 to 600 °C, and these values decrease little at higher temperature. Average pore diameter of both samples shows the inverse trends with those of BET specific surface area. Pore structure and surface morphology are both developed at lower temperature range leading to the increase of fractal dimensions (D1 and D2), indicating an increase in the surface and space roughness of samples. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.
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effect of calcium Magnesium Acetate on the forming property and fractal dimension of sludge pore structure during combustion
Bioresource Technology, 2015Co-Authors: Lihui Zhang, Feng Duan, Yaji Huang, Chiensong ChyangAbstract:The changes in pore structure characteristics of sewage sludge particles under effect of calcium Magnesium Acetate (CMA) during combustion were investigated, the samples were characterized by N2 isothermal absorption method, and the data were used to analyze the fractal properties of the obtained samples. Results show that reaction time and the mole ratio of calcium to sulfur (Ca/S ratio) have notable impact on the pore structure and morphology of solid sample. The Brunauer-Emmett-Teller (BET) specific surface area (SBET) of sample increases with Ca/S ratio, while significant decreases with reaction time. The fractal dimension D has the similar trend with that of SBET, indicating that the surface roughness of sludge increases under the effect of CMA adding, resulting in improved the sludge combustion and the desulfurization process.
Tarlok S Banipal - One of the best experts on this subject based on the ideXlab platform.
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volumetric properties of some α ω aminocarboxylic acids in aqueous sodium Acetate and Magnesium Acetate solutions at t 288 15 to 318 15 k
Journal of Chemical & Engineering Data, 2010Co-Authors: Tarlok S Banipal, Gagandeep K Kahlon, Jasbir Kaur, Kultar Singh, Vishu Mehra, Raghav Chawla, Parampaul K BanipalAbstract:Densities, ρ, of glycine (GLY), 4-aminobutyric acid (4-ABA), and 6-aminocaproic acid (6-ACA) in water and in aqueous solutions of sodium Acetate (SA) and Magnesium Acetate (MA) having a molality of (0.10, 0.25, 0.50 and 1.00) mol·kg−1 have been determined by using a vibrating-tube digital densimeter at T = (288.15 to 318.15) K. These data have been used to calculate the apparent molar volumes, Vϕ, of the studied α,ω-aminocarboxylic acids. The partial molar volumes, V2,m0, at infinite dilution are evaluated and further used to obtain the corresponding transfer volumes, ΔtrV2,m0, for α,ω-aminocarboxylic acids from water to aqueous SA and MA solutions. Partial molar expansibilities, VE0, of α,ω-aminocarboxylic acids and interaction coefficients have been calculated. The ΔtrV2,m0 values for the α,ω-aminocarboxylic acids are positive, and these values increase with an increase in the concentration of SA and MA as well as with temperature. The results obtained have been rationalized in terms of various interact...
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interactions of some peptides with sodium Acetate and Magnesium Acetate in aqueous solutions at 298 15 k a volumetric approach
Journal of Molecular Liquids, 2008Co-Authors: Tarlok S Banipal, Damanjit Kaur, Parampaul K Banipal, Gagandeep SinghAbstract:Abstract The apparent molar volumes, Vϕ of diglycine, triglycine and glycyl- l -leucine have been determined in water and in aqueous sodium Acetate (0.5, 1.0, 2.0, and 4.0 mB) and Magnesium Acetate (0.5, 1.0, 1.5, and 2.0 mB) solutions at 298.15 K by the measurement of densities using vibrating-tube digital densimeter. The partial molar volumes, V2,m0 obtained from Vϕ have been used to calculate the partial molar volumes of transfer, ΔtrV2,m0 for these peptides from water to aqueous solutions of sodium Acetate (SA) and Magnesium Acetate (MA) solutions. The hydration numbers, nH and volumetric interaction coefficients have also been calculated. The ΔtrV2,m0 data suggest that ion-charged/or peptide group interactions of peptides are stronger with MA in comparison to SA.
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thermodynamic and transport properties of l serine and l threonine in aqueous sodium Acetate and Magnesium Acetate solutions at t 298 15 k
The Journal of Chemical Thermodynamics, 2007Co-Authors: Tarlok S Banipal, Damanjit Kaur, Parampaul K Banipal, Gagandeep SinghAbstract:Abstract The apparent molar volumes, V2,ϕ, apparent molar adiabatic compressibilities, κS,2,ϕ, and relative viscosities, ηr, of l -serine and l -threonine in different concentrations of aqueous sodium Acetate and Magnesium Acetate solutions at T = 298.15 K have been obtained from the measurements of densities, speed of sound, and flow time, respectively. These data are used to derive the partial molar volumes, V 2 ∘ , partial molar adiabatic compressibilities, κ S , 2 ∘ (at infinite dilution), and viscosity B-coefficients. The corresponding quantities of transfer, (ΔtV0, Δ t κ S , 2 ∘ , and ΔtB), have been obtained. The activation free energy, Δ μ 2 ∘ ≠ , for viscous flow has been calculated for l -serine and l -threonine in aqueous solutions. The hydration numbers, nH, side chain contributions, and interaction coefficients have also been calculated. The values of V 2 ∘ , κ S , 2 ∘ , viscosity B-coefficient, and Δ μ 2 ∘ ≠ for viscous flow increase with the concentration of sodium Acetate and Magnesium Acetate solutions. The influence of Magnesium Acetate on the transfer properties is greater than sodium Acetate in aqueous solutions. A comparison of ΔtV0, Δ κ S , 2 ∘ , and ΔtB values for l -serine and l -threonine with the reported data for dl -α-alanine and dl -α-amino-n-butyric acid in aqueous sodium Acetate and Magnesium Acetate solutions shows that the values are greater for l -serine and l -threonine at the same concentration of sodium Acetate and Magnesium Acetate.
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effect of Magnesium Acetate on the volumetric and transport behavior of some amino acids in aqueous solutions at 298 15 k
The Journal of Chemical Thermodynamics, 2006Co-Authors: Tarlok S Banipal, Damanjit Kaur, Parampaul K BanipalAbstract:Abstract Densities, ρ , and viscosities, η , of glycine, dl -α-alanine, dl -α-amino- n -butyric acid, l -leucine and l -phenylalanine in 0.5, 1.0, 1.5 and 2.0 m B of aqueous Magnesium Acetate solutions at 298.15 K have been measured as a function of concentration of amino acids using vibrating tube-digital densimeter and Ubbelohde capillary type viscometer, respectively. The apparent molar volumes, V ϕ , and relative viscosities, η r , of amino acids have been derived. The partial molar volume at infinite dilution, V 2 0 , and viscosity B -coefficient obtained from these data have been used to calculate the corresponding transfer parameters, Δ t V 0 , and Δ t B , for the studied amino acids from water to aqueous Magnesium Acetate solutions. The activation free energies, Δ μ 2 0 ≠ , for the viscous flow of solutions have been obtained by application of the transition-state theory to the viscosity B -coefficient data. The interaction coefficients and hydration number, n H , of amino acids in aqueous solutions have also been calculated to see the effect of Magnesium Acetate on the hydration of amino acids. The contribution of the zwitterionic end groups ( NH 3 + , COO − ) and (CH 2 ) group of the amino acids to V 2 0 , viscosity B -coefficient and Δ μ 2 0 ≠ have been calculated. These results have been rationalized in terms of the hydration of hydrophilic and hydrophobic parts of amino acids.
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effect of sodium Acetate and Magnesium Acetate on the solution behavior of some amino acids in water at 298 15 k a compressibility approach
Zeitschrift für Physikalische Chemie, 2006Co-Authors: Tarlok S Banipal, Damanjit Kaur, Parampaul K BanipalAbstract:Apparent molar adiabatic compressibility, K 2,Φ,S , of glycine, DL-α-alanine, DL-α-amino-n-butyric acid, L-leucine and L-phenylalanine in water and in (0.5, 1.0, 2.0, 4.0, 5.5 mol kg -1 ) aqueous sodium Acetate and in (0.5, 1.0, 1.5, 2.0 mol kg -1 ) aqueous Magnesium Acetate solutions has been determined from sound velocity, u, measurements at 298.15 K. The partial molar adiabatic compressibilities at infinite dilution, K 0 2,S , obtained from K 2,Φ,S data have been used to calculate the corresponding partial molar adiabatic compressibilities of transfer at infinite dilution, Δ t K 0 2,S , from water to aqueous sodium Acetate and Magnesium Acetate (cosolutes) solutions. The Δ t K 0 2.S values are positive for the studied amino acids in case of both the cosolutes and the values increase with the increase of the concentrations of both the cosolutes. The trends of Δ t K 0 2.S have been rationalized in terms of the hydration of hydrophilic and hydrophobic parts of the amino acids studied. The interaction coefficients and hydration number, n H , have also been calculated and are discussed in terms of the dehydration effect of sodium Acetate and Magnesium Acetate upon the amino acids in solutions. Attempt has been made to correlate these results with the earlier reported volumetric and viscometric studies for the same systems.
Yi Zhang - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation of enhanced carbonation by solvent extraction for indirect co2 mineral sequestration
Greenhouse Gases-Science and Technology, 2014Co-Authors: Huiquan Li, Yi ZhangAbstract:An indirect CO 2 mineral sequestration involving two separated steps with acetic acid as a recycling medium provides a promising method for CO 2 sequestration as well as the minimum CO 2 emission for calcium carbonate production. In such an indirect route, the calcium carbonate production in the second gas‐liquid reactive crystallization step has been challenged by low carbonation efficiency. This paper describes significant enhancement of the second step by coupling reactive crystallization and solvent extraction with the introduction of the organic solvent, tributyl phosphate (TBP), to the process. Based on the reaction mechanism of this enhanced carbonation process, many influencing factors including stirring speed, phase ratio, reaction time, reaction temperature, CO 2 partial pressure, and the composition of the initial aqueous solution, were studied. Given the operating conditions of 60 min reaction time, 500 rpm stirring speed, organic‐to‐aqueous phase volume ratio of 1, 80 °C reaction temperature, 4.0 MPa CO 2 partial pressure, and initial pH of 7, the obtained crystallization conversion in the second step was found to increase from 20% to above 50%, with the incorporation of TBP and the addition of Magnesium Acetate.
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experimental investigation of enhanced carbonation by solvent extraction for indirect co2 mineral sequestration
Greenhouse Gases-Science and Technology, 2014Co-Authors: Weijun Bao, Yi ZhangAbstract:An indirect CO2 mineral sequestration involving two separated steps with acetic acid as a recycling medium provides a promising method for CO2 sequestration as well as the minimum CO2 emission for calcium carbonate production. In such an indirect route, the calcium carbonate production in the second gas-liquid reactive crystallization step has been challenged by low carbonation efficiency. This paper describes significant enhancement of the second step by coupling reactive crystallization and solvent extraction with the introduction of the organic solvent, tributyl phosphate (TBP), to the process. Based on the reaction mechanism of this enhanced carbonation process, many influencing factors including stirring speed, phase ratio, reaction time, reaction temperature, CO2 partial pressure, and the composition of the initial aqueous solution, were studied. Given the operating conditions of 60 min reaction time, 500 rpm stirring speed, organic-to-aqueous phase volume ratio of 1, 80 degrees C reaction temperature, 4.0 MPa CO2 partial pressure, and initial pH of 7, the obtained crystallization conversion in the second step was found to increase from 20% to above 50%, with the incorporation of TBP and the addition of Magnesium Acetate. (C) 2014 Society of Chemical Industry and John Wiley & Sons, Ltd
