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Kaichee Loh - One of the best experts on this subject based on the ideXlab platform.
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importance of uniform distribution of impregnated Trioctylphosphine Oxide in hollow fiber membranes for simultaneous extraction stripping of phenol
Chemical Engineering Journal, 2017Co-Authors: Kreeti Das, Prashant Praveen, Kaichee LohAbstract:Abstract Trioctylphosphine Oxide (TOPO) was impregnated in polypropylene hollow fiber membranes. The impregnation process was optimized and a uniform distribution of TOPO was achieved within the membrane walls, when the membranes were treated with a carrier solution containing 600 mg/L TOPO, and air-dried for 30 min at a low air flow rate ( Re air = 9.2). The resulting extractant impregnated hollow fiber membranes (EIHFM) were characterized by scanning electron microscopy, water entry pressure, gas permeability and mercury porosimetry analysis, all of which showed significant structural and morphological changes in the EIHFMs; pore size, porosity and tortuosity were estimated to be 0.5 μm, 0.09 and 33, respectively. The EIHFMs exhibited high mass transfer rates and removal efficiency during simultaneous extraction and stripping of phenol. At an initial phenol concentration of 200 mg/L, 99% phenol was extracted from the wastewater within 7 h, whereas more than 91% phenol was recovered in the stripping solution, yielding a concentration factor of 1.79. The performance of the EIHFMs did not change significantly during consequent operations under identical conditions, indicating the stability of impregnation. These results suggest that uniformly impregnated TOPO-based EIHFMs can be promising in the recovery of phenols from wastewater.
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solid liquid extraction equilibria of phenolic compounds with Trioctylphosphine Oxide impregnated in polymeric membranes
Chemosphere, 2016Co-Authors: Prashant Praveen, Kaichee LohAbstract:Abstract Trioctylphosphine Oxide based extractant impregnated membranes (EIM) were used for extraction of phenol and its methyl, hydroxyl and chloride substituted derivatives. The distribution coefficients of the phenols varied from 2 to 234, in the order of 1-napthol > p -chlorophenol > m -cresol > p -cresol > o -cresol > phenol > catechol > pyrogallol > hydroquinone, when initial phenols loadings was varied in 100–2000 mg/L. An extraction model, based on the law of mass action, was formulated to predict the equilibrium distribution of the phenols. The model was in excellent agreement (R 2 > 0.97) with the experimental results at low phenols concentrations ( 2 > 0.95), which signified high mass transfer resistance in the EIMs. Examination of the effects of ring substitution on equilibrium, and bivariate statistical analysis between the amounts of phenols extracted into the EIMs and factors affecting phenols interaction with TOPO, indicated the dominant role of hydrophobicity in equilibrium determination. These results improve understanding of the solid/liquid equilibrium process between phenols and the EIMs, and these will be useful in designing phenol recovery process from wastewater.
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solventless extraction stripping of phenol using Trioctylphosphine Oxide impregnated hollow fiber membranes experimental modeling analysis
Chemical Engineering Journal, 2014Co-Authors: Prashant Praveen, Kaichee LohAbstract:Abstract Trioctylphosphine Oxide (TOPO) was impregnated in polypropylene hollow fiber membranes by soaking the membranes first with TOPO containing dichloromethane, and subsequent evaporation of dichloromethane from the membranes. The resulting extractant impregnated hollow fiber membranes (EIHFM) recorded a 60% increase in weight from 0.48 g to 0.77 g. Further evidence of TOPO impregnation was obtained by visualizing TOPO deposition within the membrane walls through scanning electron microscopy. Extraction of 200–2700 mg/L phenol by the EIHFMs was characterized by high uptake rate and capacity, and equilibrium was attained within 1–3 h of contact. Stripping using 0.2 M sodium hydrOxide was effective and EIHFM performance remained stable during 10 repeated cycles of extraction and stripping. The mass transfer kinetics of phenol was examined using pseudo-first-order, pseudo-second-order and intraparticle diffusion models, while the distribution equilibrium was modeled using Langmuir, Freundlich, Temkin and Redlich–Peterson isotherms. A kinetics model was also developed based on steady state resistance-in-series approach. The overall mass transfer coefficient was determined and diffusion through the boundary layer was found to be the rate limiting step. The effects of feed phenol concentrations and flow rates on extraction performance of the EIHFMs were simulated, and excellent correlation was obtained between the experimental and the simulated results. These results indicate that the TOPO-based EIHFMs can be used for an effective, sustainable and a relatively solventless extraction of phenol.
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two phase biodegradation of phenol in Trioctylphosphine Oxide impregnated hollow fiber membrane bioreactor
Biochemical Engineering Journal, 2013Co-Authors: Prashant Praveen, Kaichee LohAbstract:Abstract A hollow fiber membrane bioreactor using Trioctylphosphine Oxide (TOPO) impregnated in polypropylene hollow fiber membranes was developed for two-phase biodegradation of phenol using Pseudomonas putida ATCC 11172. Scanning electron microscopy revealed white deposits of TOPO impregnated non-uniformly within the cross sections and surfaces of the membranes. The extractant impregnated membranes exhibited high adsorption capacity and rates, whereas biodegradation of 800–2500 mg/L phenol at 200 mL volume in the extractant impregnated hollow fiber membrane bioreactor (EIHFMB) was characterized by high cell growth and biodegradation rates. For example, 1000 mg/L phenol was completely degraded within 12 h at a specific growth rate of 0.73 h−1 while the biomass yield and average biodegradation rate were 0.31 g/g and 86 mg/L h, respectively. The biodegradation capacity and rate in the EIHFMB were improved by increasing the effective length of the fibers by 50%, as demonstrated during the biodegradation of 3000 mg/L phenol. The adsorption/desorption rates were also enhanced with increasing aqueous phase flow rate. EIHFMB performance remained unchanged over 400 h of operation under various operating conditions suggesting the stability of TOPO impregnation within the membrane. These results indicate the use of EIHFMB as a promising technology in solvent-free two-phase biodegradation of phenolic compounds.
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Trioctylphosphine Oxide impregnated hollow fiber membranes for removal of phenol from wastewater
Journal of Membrane Science, 2013Co-Authors: Prashant Praveen, Kaichee LohAbstract:Abstract Trioctylphosphine Oxide (TOPO) was immobilized in polypropylene hollow fiber membranes for removal of phenol from wastewater. Scanning electron microscopy showed white deposits of TOPO dispersed non-uniformly within the resulting extractant-impregnated hollow fiber membranes (EIHFM). The EIHFMs manifested high adsorption capacity and mass transfer rates, with adsorption equilibrium attained within 10–30 min of operation. Experimental equilibrium adsorption capacities with a feed of 1000 mg/L phenol were 32, 42, 52 and 57 mg/g at 50, 100, 200 and 400 g/L TOPO, respectively. During repeated operation with 1000 mg/L phenol, the adsorption capacities of the EIHFMs remained stable at 32.2±1.3 and 52.3±0.9 mg/g for 10 subsequent runs at TOPO concentrations of 50 and 100 g/L, respectively. The EIHFMs, when used as adsorbents in a two phase partitioning bioreactor, alleviated substrate inhibition on Pseudomonas putida by rapidly adsorbing phenol to sub-inhibitory levels. Biodegradation of 1000 and 2000 mg/L phenol was completed within 26 and 36 h, respectively. These results suggest that the EIHFM is a promising technology for solventless extraction of aromatic compounds in wastewater treatment.
John D. Holbrey - One of the best experts on this subject based on the ideXlab platform.
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Hydrophobic functional liquids based on Trioctylphosphine Oxide (TOPO) and carboxylic acids
Physical chemistry chemical physics : PCCP, 2020Co-Authors: Emily L. Byrne, Mark Gilmore, John D. Holbrey, Ruairi O'donnell, Nancy Artioli, Małgorzata Swadźba-kwaśnyAbstract:Trioctylphosphine Oxide (TOPO) is a hydrophobic extracting agent used in a number of commercially important separations of valuable solutes from aqueous streams (with examples ranging from lanthanides, through gallium, to carboxylic acids). TOPO is traditionally used as a solute in kerosene, its extraction efficiency limited by its solubility in the organic diluents. In this work, eighteen hydrogen bond donors (HBDs) were screened for their capacity to liquefy TOPO, employing strategies used to design deep eutectic solvents (DES). The selected HBDs were all useful in separations and were designed to formulate solvent-free, hydrophobic, bi-functional liquid extracting agents. Some TOPO:HBD mixtures yielded hydrophobic liquids that offer potential to be extremely efficient extractants, incorporating high intrinsic concentrations of TOPO. Following this initial screening, two systems: TOPO:malonic acid and TOPO:levulinic acid, were selected for detailed physico-chemical characterisation across their complete compositional ranges. Phase diagrams, thermal stabilities and the mechanism of thermal decomposition are reported, along with densities and insights from 31P NMR spectroscopic studies. The work was concluded with a proof-of-concept demonstration of the use of the TOPO:malonic acid (2 : 1 mol ratio) mixture for the extraction of gallium from acidic chloride feedstock (simulated pre-digestate of zinc leach residue). The loading capacity of the TOPO:malonic acid extractant was three orders of magnitude greater than that of the literature benchmark, encouraging further application-oriented studies.
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Hydrophobic Deep Eutectic Solvents Incorporating Trioctylphosphine Oxide: Advanced Liquid Extractants
ACS Sustainable Chemistry & Engineering, 2018Co-Authors: Mark Gilmore, Eadaoin Mccourt, Francis Connolly, Peter Nockemann, Małgorzata Swadźba-kwaśny, John D. HolbreyAbstract:A low viscosity, hydrophobic eutectic solvent based on Trioctylphosphine Oxide (TOPO) has been developed and characterized, and its use as an extractant demonstrated for liquid–liquid separation of uranyl nitrate from aqueous acid. This strategy of liquefying the active extracting agent as a eutectic liquid produced liquids that contain an intrinsically high concentration of TOPO (ca. 80 wt %, 1.875 mol L–1 at χTOPO = 0.50) and renders the use of an organic (hydrocarbon) diluent redundant.
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hydrophobic deep eutectic solvents incorporating Trioctylphosphine Oxide advanced liquid extractants
ACS Sustainable Chemistry & Engineering, 2018Co-Authors: Mark Gilmore, Eadaoin Mccourt, Francis Connolly, Peter Nockemann, Malgorzata Swadźbakwaśny, John D. HolbreyAbstract:A low viscosity, hydrophobic eutectic solvent based on Trioctylphosphine Oxide (TOPO) has been developed and characterized, and its use as an extractant demonstrated for liquid–liquid separation of...
Mark Gilmore - One of the best experts on this subject based on the ideXlab platform.
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Hydrophobic functional liquids based on Trioctylphosphine Oxide (TOPO) and carboxylic acids
Physical chemistry chemical physics : PCCP, 2020Co-Authors: Emily L. Byrne, Mark Gilmore, John D. Holbrey, Ruairi O'donnell, Nancy Artioli, Małgorzata Swadźba-kwaśnyAbstract:Trioctylphosphine Oxide (TOPO) is a hydrophobic extracting agent used in a number of commercially important separations of valuable solutes from aqueous streams (with examples ranging from lanthanides, through gallium, to carboxylic acids). TOPO is traditionally used as a solute in kerosene, its extraction efficiency limited by its solubility in the organic diluents. In this work, eighteen hydrogen bond donors (HBDs) were screened for their capacity to liquefy TOPO, employing strategies used to design deep eutectic solvents (DES). The selected HBDs were all useful in separations and were designed to formulate solvent-free, hydrophobic, bi-functional liquid extracting agents. Some TOPO:HBD mixtures yielded hydrophobic liquids that offer potential to be extremely efficient extractants, incorporating high intrinsic concentrations of TOPO. Following this initial screening, two systems: TOPO:malonic acid and TOPO:levulinic acid, were selected for detailed physico-chemical characterisation across their complete compositional ranges. Phase diagrams, thermal stabilities and the mechanism of thermal decomposition are reported, along with densities and insights from 31P NMR spectroscopic studies. The work was concluded with a proof-of-concept demonstration of the use of the TOPO:malonic acid (2 : 1 mol ratio) mixture for the extraction of gallium from acidic chloride feedstock (simulated pre-digestate of zinc leach residue). The loading capacity of the TOPO:malonic acid extractant was three orders of magnitude greater than that of the literature benchmark, encouraging further application-oriented studies.
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Hydrophobic Deep Eutectic Solvents Incorporating Trioctylphosphine Oxide: Advanced Liquid Extractants
ACS Sustainable Chemistry & Engineering, 2018Co-Authors: Mark Gilmore, Eadaoin Mccourt, Francis Connolly, Peter Nockemann, Małgorzata Swadźba-kwaśny, John D. HolbreyAbstract:A low viscosity, hydrophobic eutectic solvent based on Trioctylphosphine Oxide (TOPO) has been developed and characterized, and its use as an extractant demonstrated for liquid–liquid separation of uranyl nitrate from aqueous acid. This strategy of liquefying the active extracting agent as a eutectic liquid produced liquids that contain an intrinsically high concentration of TOPO (ca. 80 wt %, 1.875 mol L–1 at χTOPO = 0.50) and renders the use of an organic (hydrocarbon) diluent redundant.
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hydrophobic deep eutectic solvents incorporating Trioctylphosphine Oxide advanced liquid extractants
ACS Sustainable Chemistry & Engineering, 2018Co-Authors: Mark Gilmore, Eadaoin Mccourt, Francis Connolly, Peter Nockemann, Malgorzata Swadźbakwaśny, John D. HolbreyAbstract:A low viscosity, hydrophobic eutectic solvent based on Trioctylphosphine Oxide (TOPO) has been developed and characterized, and its use as an extractant demonstrated for liquid–liquid separation of...
Prashant Praveen - One of the best experts on this subject based on the ideXlab platform.
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importance of uniform distribution of impregnated Trioctylphosphine Oxide in hollow fiber membranes for simultaneous extraction stripping of phenol
Chemical Engineering Journal, 2017Co-Authors: Kreeti Das, Prashant Praveen, Kaichee LohAbstract:Abstract Trioctylphosphine Oxide (TOPO) was impregnated in polypropylene hollow fiber membranes. The impregnation process was optimized and a uniform distribution of TOPO was achieved within the membrane walls, when the membranes were treated with a carrier solution containing 600 mg/L TOPO, and air-dried for 30 min at a low air flow rate ( Re air = 9.2). The resulting extractant impregnated hollow fiber membranes (EIHFM) were characterized by scanning electron microscopy, water entry pressure, gas permeability and mercury porosimetry analysis, all of which showed significant structural and morphological changes in the EIHFMs; pore size, porosity and tortuosity were estimated to be 0.5 μm, 0.09 and 33, respectively. The EIHFMs exhibited high mass transfer rates and removal efficiency during simultaneous extraction and stripping of phenol. At an initial phenol concentration of 200 mg/L, 99% phenol was extracted from the wastewater within 7 h, whereas more than 91% phenol was recovered in the stripping solution, yielding a concentration factor of 1.79. The performance of the EIHFMs did not change significantly during consequent operations under identical conditions, indicating the stability of impregnation. These results suggest that uniformly impregnated TOPO-based EIHFMs can be promising in the recovery of phenols from wastewater.
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solid liquid extraction equilibria of phenolic compounds with Trioctylphosphine Oxide impregnated in polymeric membranes
Chemosphere, 2016Co-Authors: Prashant Praveen, Kaichee LohAbstract:Abstract Trioctylphosphine Oxide based extractant impregnated membranes (EIM) were used for extraction of phenol and its methyl, hydroxyl and chloride substituted derivatives. The distribution coefficients of the phenols varied from 2 to 234, in the order of 1-napthol > p -chlorophenol > m -cresol > p -cresol > o -cresol > phenol > catechol > pyrogallol > hydroquinone, when initial phenols loadings was varied in 100–2000 mg/L. An extraction model, based on the law of mass action, was formulated to predict the equilibrium distribution of the phenols. The model was in excellent agreement (R 2 > 0.97) with the experimental results at low phenols concentrations ( 2 > 0.95), which signified high mass transfer resistance in the EIMs. Examination of the effects of ring substitution on equilibrium, and bivariate statistical analysis between the amounts of phenols extracted into the EIMs and factors affecting phenols interaction with TOPO, indicated the dominant role of hydrophobicity in equilibrium determination. These results improve understanding of the solid/liquid equilibrium process between phenols and the EIMs, and these will be useful in designing phenol recovery process from wastewater.
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solventless extraction stripping of phenol using Trioctylphosphine Oxide impregnated hollow fiber membranes experimental modeling analysis
Chemical Engineering Journal, 2014Co-Authors: Prashant Praveen, Kaichee LohAbstract:Abstract Trioctylphosphine Oxide (TOPO) was impregnated in polypropylene hollow fiber membranes by soaking the membranes first with TOPO containing dichloromethane, and subsequent evaporation of dichloromethane from the membranes. The resulting extractant impregnated hollow fiber membranes (EIHFM) recorded a 60% increase in weight from 0.48 g to 0.77 g. Further evidence of TOPO impregnation was obtained by visualizing TOPO deposition within the membrane walls through scanning electron microscopy. Extraction of 200–2700 mg/L phenol by the EIHFMs was characterized by high uptake rate and capacity, and equilibrium was attained within 1–3 h of contact. Stripping using 0.2 M sodium hydrOxide was effective and EIHFM performance remained stable during 10 repeated cycles of extraction and stripping. The mass transfer kinetics of phenol was examined using pseudo-first-order, pseudo-second-order and intraparticle diffusion models, while the distribution equilibrium was modeled using Langmuir, Freundlich, Temkin and Redlich–Peterson isotherms. A kinetics model was also developed based on steady state resistance-in-series approach. The overall mass transfer coefficient was determined and diffusion through the boundary layer was found to be the rate limiting step. The effects of feed phenol concentrations and flow rates on extraction performance of the EIHFMs were simulated, and excellent correlation was obtained between the experimental and the simulated results. These results indicate that the TOPO-based EIHFMs can be used for an effective, sustainable and a relatively solventless extraction of phenol.
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two phase biodegradation of phenol in Trioctylphosphine Oxide impregnated hollow fiber membrane bioreactor
Biochemical Engineering Journal, 2013Co-Authors: Prashant Praveen, Kaichee LohAbstract:Abstract A hollow fiber membrane bioreactor using Trioctylphosphine Oxide (TOPO) impregnated in polypropylene hollow fiber membranes was developed for two-phase biodegradation of phenol using Pseudomonas putida ATCC 11172. Scanning electron microscopy revealed white deposits of TOPO impregnated non-uniformly within the cross sections and surfaces of the membranes. The extractant impregnated membranes exhibited high adsorption capacity and rates, whereas biodegradation of 800–2500 mg/L phenol at 200 mL volume in the extractant impregnated hollow fiber membrane bioreactor (EIHFMB) was characterized by high cell growth and biodegradation rates. For example, 1000 mg/L phenol was completely degraded within 12 h at a specific growth rate of 0.73 h−1 while the biomass yield and average biodegradation rate were 0.31 g/g and 86 mg/L h, respectively. The biodegradation capacity and rate in the EIHFMB were improved by increasing the effective length of the fibers by 50%, as demonstrated during the biodegradation of 3000 mg/L phenol. The adsorption/desorption rates were also enhanced with increasing aqueous phase flow rate. EIHFMB performance remained unchanged over 400 h of operation under various operating conditions suggesting the stability of TOPO impregnation within the membrane. These results indicate the use of EIHFMB as a promising technology in solvent-free two-phase biodegradation of phenolic compounds.
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Trioctylphosphine Oxide impregnated hollow fiber membranes for removal of phenol from wastewater
Journal of Membrane Science, 2013Co-Authors: Prashant Praveen, Kaichee LohAbstract:Abstract Trioctylphosphine Oxide (TOPO) was immobilized in polypropylene hollow fiber membranes for removal of phenol from wastewater. Scanning electron microscopy showed white deposits of TOPO dispersed non-uniformly within the resulting extractant-impregnated hollow fiber membranes (EIHFM). The EIHFMs manifested high adsorption capacity and mass transfer rates, with adsorption equilibrium attained within 10–30 min of operation. Experimental equilibrium adsorption capacities with a feed of 1000 mg/L phenol were 32, 42, 52 and 57 mg/g at 50, 100, 200 and 400 g/L TOPO, respectively. During repeated operation with 1000 mg/L phenol, the adsorption capacities of the EIHFMs remained stable at 32.2±1.3 and 52.3±0.9 mg/g for 10 subsequent runs at TOPO concentrations of 50 and 100 g/L, respectively. The EIHFMs, when used as adsorbents in a two phase partitioning bioreactor, alleviated substrate inhibition on Pseudomonas putida by rapidly adsorbing phenol to sub-inhibitory levels. Biodegradation of 1000 and 2000 mg/L phenol was completed within 26 and 36 h, respectively. These results suggest that the EIHFM is a promising technology for solventless extraction of aromatic compounds in wastewater treatment.
Masakazu Matsui - One of the best experts on this subject based on the ideXlab platform.
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the synergic extraction of rare earth metals with ortho substituted 1 phenyl 3 methyl 4 aroyl 5 pyrazolones and Trioctylphosphine Oxide
Analytical Sciences, 1997Co-Authors: Hiroshi Mukai, Shigeo Umetani, Masakazu MatsuiAbstract:The synergic extractions of rare earth metals (scandium, lanthanum and lutetium, M 3+ ) with ortho-substituted 4-aroyl derivatives of 1-phenyl-3-methyl-5-pyrazolone (HA) and a neutral ligand, Trioctylphosphine Oxide (TOPO, L) in benzene were studied. Eight ortho-substituted 4aroyl derivatives of pyrazolone have been prepared. Linear relationships between the extraction constants and the acid dissociation constants of aroylpyrazolones were obtained when TOPO was not added. The metal chelates of aroylpyrazolones react with TOPO to form MA 3 L and MA 3 L 2 types of adducts in the synergic extractions. Obvious steric hindrances of the terminal substituents at orthoposition of 4-aroyl group of the ligands on the adduct formation reaction were observed by the comparison of adduct formation constants.
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highly acidic extractant 4 benzoyl 3 phenyl 5 isoxazolone the synergistic extraction of alkaline earth and alkali metals combined with Trioctylphosphine Oxide or bis diphenylphosphinyl methane
Bulletin of the Chemical Society of Japan, 1995Co-Authors: Shigeo Umetani, Takayuki Sasaki, Takeshi Tomita, Masakazu MatsuiAbstract:The synergistic extraction of alkaline earth (Mg2+, Ca2+, Sr2+, and Ba2+) and alkali metals (Li+ and Na+) with a highly acidic extractant, 4-benzoyl-3-phenyl-5-isoxazolone (HPBI), combined with a synergist, Trioctylphosphine Oxide (TOPO) or bis(diphenylphosphinyl)methane (BDPPM), has been examined. The results were compared with those of the analogous extractants, 4-benzoyl-3-methyl-1-phenyl-5-pyrazolone (HPMBP) and 3-methyl-1-phenyl-4-trifluoroacetyl-5-pyrazolone (HPMTFP) which are also highly acidic extractants derived from heterocyclic compounds. Owing to the strong acidity of HPBI (pKa = 1.23), alkaline earths were extracted quantitatively from a very low pH region. Especially, alkaline earths were readily extracted at pH 2—3 with the bidentate phosphine Oxide, BDPPM, as a synergist. The extraction of Li+ and Na+ with HPBI and TOPO was inferior to that with HPMBP and HPMTFP, though their acidity is weaker. In contrast to the excellent extractability of HPBI, its separation was poor. The extractability...
