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Allan K Bertram - One of the best experts on this subject based on the ideXlab platform.
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liquid liquid phase separation in particles containing organics mixed with ammonium sulfate ammonium bisulfate ammonium nitrate or sodium chloride
Atmospheric Chemistry and Physics, 2013Co-Authors: Yuan You, Lindsay Renbaumwolff, Allan K BertramAbstract:Abstract. As the relative humidity varies from high to low values in the atmosphere, particles containing organic species and Inorganic Salts may undergo liquid–liquid phase separation. The majority of the laboratory work on this subject has used ammonium sulfate as the Inorganic Salt. In the following we studied liquid–liquid phase separation in particles containing organics mixed with the following Salts: ammonium sulfate, ammonium bisulfate, ammonium nitrate and sodium chloride. In each experiment one organic was mixed with one Inorganic Salt and the liquid–liquid phase separation relative humidity (SRH) was determined. Since we studied 23 different organics mixed with four different Salts, a total of 92 different particle types were investigated. Out of the 92 types, 49 underwent liquid–liquid phase separation. For all the Inorganic Salts, liquid–liquid phase separation was never observed when the oxygen-to-carbon elemental ratio (O : C) g 0.8 and was always observed for O : C
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liquid liquid phase separation in particles containing organics mixed with ammonium sulfate ammonium bisulfate ammonium nitrate or sodium chloride
Atmospheric Chemistry and Physics, 2013Co-Authors: Lindsay Renbaumwolff, Allan K BertramAbstract:Abstract. As the relative humidity varies from high to low values in the atmosphere, particles containing organic species and Inorganic Salts may undergo liquid–liquid phase separation. The majority of the laboratory work on this subject has used ammonium sulfate as the Inorganic Salt. In the following we studied liquid–liquid phase separation in particles containing organics mixed with the following Salts: ammonium sulfate, ammonium bisulfate, ammonium nitrate and sodium chloride. In each experiment one organic was mixed with one Inorganic Salt and the liquid–liquid phase separation relative humidity (SRH) was determined. Since we studied 23 different organics mixed with four different Salts, a total of 92 different particle types were investigated. Out of the 92 types, 49 underwent liquid–liquid phase separation. For all the Inorganic Salts, liquid–liquid phase separation was never observed when the oxygen-to-carbon elemental ratio (O : C) g 0.8 and was always observed for O : C 4 ) 2 SO 4 g NH 4 HSO 4 g NaCl g NH 4 NO 3 . This trend is consistent with previous Salting out studies and the Hofmeister series. Based on the range of O : C values found in the atmosphere and the current results, liquid–liquid phase separation is likely a frequent occurrence in both marine and non-marine environments.
Vicki Chen - One of the best experts on this subject based on the ideXlab platform.
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effect of Inorganic Salt blending on the co2 separation performance and morphology of pebax1657 ionic liquid gel membranes
Industrial & Engineering Chemistry Research, 2019Co-Authors: Winny Fam, Jaleh Mansouri, Jingwei Hou, Vicki ChenAbstract:Gel membranes comprising Inorganic Salt, molten Salt or ionic liquid (IL), and Pebax1657 were prepared by blending the three components in ethanol/water mixture, and their carbon dioxide separation...
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Effect of Inorganic Salt Blending on the CO2 Separation Performance and Morphology of Pebax1657/Ionic Liquid Gel Membranes
2019Co-Authors: Winny Fam, Jaleh Mansouri, Jingwei Hou, Vicki ChenAbstract:Gel membranes comprising Inorganic Salt, molten Salt or ionic liquid (IL), and Pebax1657 were prepared by blending the three components in ethanol/water mixture, and their carbon dioxide separation properties were evaluated. To probe the effects of Inorganic Salt types and concentrations, a small amount of common Inorganic Salts, such as sodium chloride (NaCl), calcium chloride (CaCl2), and sodium sulfate (Na2SO4) were first doped into neat Pebax membranes. The thermal properties, surface chemistry, and gas separation performance of the free-standing membranes were evaluated using differential scanning calorimetry, Fourier-transform infrared spectroscopy, and gas permeation tests. CaCl2-doped membranes gave the best performance due to the high water content and cross-linking between the Salt cation and polyamide segments, which resulted in lower polymer crystallinity. Further incorporation of 1-ethyl-3-methylimidazolium tetrafluoroborate IL into Pebax1657/Inorganic Salt mixture to form thin film composite gel membranes improved the Inorganic Salt solubility and enhanced CO2 permeance up to 899 GPU at the expense of CO2/N2 selectivity and mechanical strength. Cyclic permeation tests using humidified feed containing a trace amount of contaminant showed stable performance although no improvement in gas pair selectivity was observed, confirming solution-diffusion mechanism through the gel membranes
Yuloong Loow - One of the best experts on this subject based on the ideXlab platform.
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deep eutectic solvent and Inorganic Salt pretreatment of lignocellulosic biomass for improving xylose recovery
Bioresource Technology, 2018Co-Authors: Yuloong Loow, Lee Fong Siow, Jamaliah Md Jahim, Abdul Wahab Mohammad, Ge Hoa Yang, Lin Yang Ang, Eng Kein New, Wen Hui TeohAbstract:Deep eutectic solvents (DESs) have received considerable attention in recent years due to their low cost, low toxicity, and biodegradable properties. In this study, a sequential pretreatment comprising of a DES (choline chloride:urea in a ratio of 1:2) and divalent Inorganic Salt (CuCl2) was evaluated, with the aim of recovering xylose from oil palm fronds (OPF). At a solid-to-liquid ratio of 1:10 (w/v), DES alone was ineffective in promoting xylose extraction from OPF. However, a combination of DES (120°C, 4h) and 0.4mol/L of CuCl2 (120°C, 30min) resulted in a pretreatment hydrolysate containing 14.76g/L of xylose, remarkably yielding 25% more xylose than the CuCl2-only pretreatment (11.87g/L). Characterization studies such as FE-SEM, BET, XRD, and FTIR confirmed the delignification of OPF when DES was implemented. Thus, the use of this integrated pretreatment system enabled xylose recoveries which were comparable with other traditional pretreatments.
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transformation of oil palm fronds into pentose sugars using copper ii sulfate pentahydrate with the assistance of chemical additive
Journal of Environmental Management, 2017Co-Authors: Yuloong LoowAbstract:Abstract Among the chemical pretreatments available for pretreating biomass, the Inorganic Salt is considered to be a relatively new but simple reagent that offers comparable pentose (C5) sugar recoveries as the conventional dilute acid hydrolysis. This study investigated the effects of different concentrations (1.5–6.0% (v/v)) of H 2 O 2 or Na 2 S 2 O 8 in facilitating CuSO 4 ·5H 2 O pretreatment for improving pentose sugar recovery from oil palm fronds. The best result was observed when 0.2 mol/L of CuSO 4 ·5H 2 O was integrated with 4.5% (v/v) of Na 2 S 2 O 8 to recover 8.2 and 0.9 g/L of monomeric xylose and arabinose, respectively in the liquid fraction. On the other hand, an addition of 1.5% (v/v) of H 2 O 2 yielded approximately 74% lesser total pentose sugars as compared to using 4.5% (v/v) Na 2 S 2 O 8 . By using CuSO 4 ·5H 2 O alone (control), only 0.8 and 1.0 g/L xylose and arabinose, respectively could be achieved. The results mirrored the importance of using chemical additives together with the Inorganic Salt pretreatment of oil palm fronds. Thus, an addition of 4.5% (v/v) of Na 2 S 2 O 8 during CuSO 4 ·5H 2 O pretreatment of oil palm fronds at 120 °C and 30 min was able to attain a total pentose sugar yield up to ∼40%.
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improvement of xylose recovery from the stalks of oil palm fronds using Inorganic Salt and oxidative agent
Energy Conversion and Management, 2017Co-Authors: Yuloong Loow, Yung Shen Lim, Khang Aik Tan, Lee Fong Siow, Jamaliah Md Jahim, Abdul Wahab MohammadAbstract:Abstract Lignocellulosic biomass is a plant dry matter that could be considered as a renewable carbon resource for the production of reducing sugar, which is an alternative building block for biofuels and chemicals. However, due to the recalcitrant nature of lignocellulosic biomass, researchers have focused their efforts on establishing cost-efficient pretreatments to reutilize the lignocellulose components within the biomass effectively. In this study, divalent (CuCl2) and trivalent (FeCl3) Inorganic Salts were used in the recovery of xylose from the stalks of oil palm fronds (OPF). Additionally, oxidizing agents such as hydrogen peroxide and sodium persulfate were tested for their effectiveness in improving Inorganic Salt pretreatment. By using Inorganic Salt alone, FeCl3 outperformed CuCl2 in terms of xylose recovery, in which 75.5 and 59.3% of xylose could be recovered from OPF using FeCl3 and CuCl2, respectively. An incorporation of sodium persulfate with CuCl2 enabled a maximum xylose recovery up to 72.0%, with no statistical difference as compared to using FeCl3 alone. The synergism between CuCl2 and sodium persulfate was attributed to the formation of unstable Cu3+ ions, which acted as a trivalent Salt. Characterization studies of the solid fraction before and after pretreatment also validated the delignification of OPF. Hence, the combination of CuCl2 and sodium persulfate was able to attain sugar yields which were comparable with other conventional pretreatments.
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recent advances in the application of Inorganic Salt pretreatment for transforming lignocellulosic biomass into reducing sugars
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Yuloong Loow, Yung Shen Lim, Khang Aik Tan, Lee Fong Siow, Jamaliah Md Jahim, Abdul Wahab Mohammad, Wen Hui TeohAbstract:Currently, the transformation of lignocellulosic biomass into value-added products such as reducing sugars is garnering attention worldwide. However, efficient hydrolysis is usually hindered by the recalcitrant structure of the biomass. Many pretreatment technologies have been developed to overcome the recalcitrance of lignocellulose such that the components can be reutilized more effectively to enhance sugar recovery. Among all of the utilized pretreatment methods, Inorganic Salt pretreatment represents a more novel method and offers comparable sugar recovery with the potential for reducing costs. The use of Inorganic Salt also shows improved performance when it is integrated with other pretreatment technologies. Hence, this paper is aimed to provide a detailed overview of the current situation for lignocellulosic biomass and its physicochemical characteristics. Furthermore, this review discusses some recent studies using Inorganic Salt for pretreating biomass and the mechanisms involved during the proce...
Lindsay Renbaumwolff - One of the best experts on this subject based on the ideXlab platform.
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liquid liquid phase separation in particles containing organics mixed with ammonium sulfate ammonium bisulfate ammonium nitrate or sodium chloride
Atmospheric Chemistry and Physics, 2013Co-Authors: Yuan You, Lindsay Renbaumwolff, Allan K BertramAbstract:Abstract. As the relative humidity varies from high to low values in the atmosphere, particles containing organic species and Inorganic Salts may undergo liquid–liquid phase separation. The majority of the laboratory work on this subject has used ammonium sulfate as the Inorganic Salt. In the following we studied liquid–liquid phase separation in particles containing organics mixed with the following Salts: ammonium sulfate, ammonium bisulfate, ammonium nitrate and sodium chloride. In each experiment one organic was mixed with one Inorganic Salt and the liquid–liquid phase separation relative humidity (SRH) was determined. Since we studied 23 different organics mixed with four different Salts, a total of 92 different particle types were investigated. Out of the 92 types, 49 underwent liquid–liquid phase separation. For all the Inorganic Salts, liquid–liquid phase separation was never observed when the oxygen-to-carbon elemental ratio (O : C) g 0.8 and was always observed for O : C
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liquid liquid phase separation in particles containing organics mixed with ammonium sulfate ammonium bisulfate ammonium nitrate or sodium chloride
Atmospheric Chemistry and Physics, 2013Co-Authors: Lindsay Renbaumwolff, Allan K BertramAbstract:Abstract. As the relative humidity varies from high to low values in the atmosphere, particles containing organic species and Inorganic Salts may undergo liquid–liquid phase separation. The majority of the laboratory work on this subject has used ammonium sulfate as the Inorganic Salt. In the following we studied liquid–liquid phase separation in particles containing organics mixed with the following Salts: ammonium sulfate, ammonium bisulfate, ammonium nitrate and sodium chloride. In each experiment one organic was mixed with one Inorganic Salt and the liquid–liquid phase separation relative humidity (SRH) was determined. Since we studied 23 different organics mixed with four different Salts, a total of 92 different particle types were investigated. Out of the 92 types, 49 underwent liquid–liquid phase separation. For all the Inorganic Salts, liquid–liquid phase separation was never observed when the oxygen-to-carbon elemental ratio (O : C) g 0.8 and was always observed for O : C 4 ) 2 SO 4 g NH 4 HSO 4 g NaCl g NH 4 NO 3 . This trend is consistent with previous Salting out studies and the Hofmeister series. Based on the range of O : C values found in the atmosphere and the current results, liquid–liquid phase separation is likely a frequent occurrence in both marine and non-marine environments.
João A. P. Coutinho - One of the best experts on this subject based on the ideXlab platform.
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1 H NMR and molecular dynamics evidence for an unexpected interaction on the origin of Salting-in/Salting-out phenomena
2014Co-Authors: Mara G. Freire, Catarina M. S. S. Neves, Artur M. S. Silva, Isabel M. Marrucho, Luís P. N. Rebelo, Jindal K. Shah, Edward J. Maginn, João A. P. CoutinhoAbstract:By employing 1 H NMR spectroscopy and molecular simulations, we provide an explanation for recent observations that the aqueous solubilities of ionic liquids exhibit Salting-out to Salting-in regimes upon addition of distinct Inorganic Salt ions. Using a typical ionic liquid [1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide], we observed the existence of preferential specific interactions between the low electrical charge density (“apolar moiety”) parts of the ionic liquid cation and the Inorganic Salts. These a priori unexpected interactions become increasingly favorable as one moves from Salting-out to Salting-in effects. More specifically, this interpretation is validated by distinct aqueous solution 1 H NMR data shifts in the ionic liquid cation upon Inorganic Salt addition. These shifts, which are well noted in the terminal and preterminal hydrogens of the alkyl chain appended to the imidazolium ring, correlate quantitatively with solubility data, both for cases where the nature of Inorganic Salt is changed, at constant concentration, and for those where the concentration of a given Inorganic Salt is varied. Molecular simulations have also been performed permitting us to garner a broader picture of the underlying mechanism and structure of this complex solvation phenomenon. These findings can now be profitably used to anticipate solution behavior upon Inorganic Salt addition wel
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ionic liquids as adjuvants for the tailored extraction of biomolecules in aqueous biphasic systems
Green Chemistry, 2010Co-Authors: Jorge F B Pereira, Mara G. Freire, Alvaro Silva Lima, João A. P. CoutinhoAbstract:The potential use of ionic liquids (ILs) as adjuvants in typical polymer-Salt aqueous systems for the separation and purification of vital biomolecules is investigated. An innovative study involving the addition of various imidazolium-based ILs to conventional PEG/Inorganic Salt aqueous biphasic systems (ABS), aiming at controlling their phase behaviour and extraction capability for L-tryptophan, is carried out here. For this purpose, phase diagrams and respective tie-lines for PEG 600/Na2SO4 ABS with the addition of small quantities of IL were established. In addition, the partition coefficients of L-tryptophan were determined in those systems. The results obtained indicate that the addition of small amounts of IL to the typical PEG/Inorganic Salt aqueous systems could largely control the extraction efficiency for L-tryptophan, and that efficiency depends on the IL employed. Salting-in inducing ILs enhance the partition coefficient of L-tryptophan for the PEG-rich phase while Salting-out inducing ILs decrease the partitioning of the amino acid. These results are an interesting advance in biotechnological separation processes regarding the extraction of biomolecules that could be used instead of the common approach of PEG functionalization.
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1h nmr and molecular dynamics evidence for an unexpected interaction on the origin of Salting in Salting out phenomena
Journal of Physical Chemistry B, 2010Co-Authors: Mara G. Freire, Catarina M. S. S. Neves, Artur M. S. Silva, Isabel M. Marrucho, Luís P. N. Rebelo, Jindal K. Shah, Edward J. Maginn, Luis M N B F Santos, João A. P. CoutinhoAbstract:By employing 1H NMR spectroscopy and molecular simulations, we provide an explanation for recent observations that the aqueous solubilities of ionic liquids exhibit Salting-out to Salting-in regimes upon addition of distinct Inorganic Salt ions. Using a typical ionic liquid [1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide], we observed the existence of preferential specific interactions between the low electrical charge density (“apolar moiety”) parts of the ionic liquid cation and the Inorganic Salts. These a priori unexpected interactions become increasingly favorable as one moves from Salting-out to Salting-in effects. More specifically, this interpretation is validated by distinct aqueous solution 1H NMR data shifts in the ionic liquid cation upon Inorganic Salt addition. These shifts, which are well noted in the terminal and preterminal hydrogens of the alkyl chain appended to the imidazolium ring, correlate quantitatively with solubility data, both for cases where the nature of inorgan...