@article { ISI:000249949800021, title = {Transesterification of alpha-haloesters and beta-ketoesters over Mg-Al-hydrotalcites (HT)-like anionic clays}, journal = {Journal of Molecular Catalysis A-Chemical}, volume = {276}, number = {1-2}, year = {2007}, month = {OCT}, pages = {158-161}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Transesterification of alpha-haloesters was achieved by reaction of alcohols in the presence of Mg-Al-HT-like anionic clays. beta-Ketoesters were also transesterified under similar conditions on reaction with alcohols with a wide variety of functional groups. (c) 2007 Elsevier B.V. All rights reserved.

}, keywords = {alpha-haloesters, beta-ketoesters, heterogeneous catalyst, Hydrotalcites, transesterification}, issn = {1381-1169}, doi = {10.1016/j.molcata.2007.07.006}, author = {Bulbule, Vivek J. and Borate, Hanumant B. and Munot, Yogesh S. and Deshpande, Vishnu H. and Sawargave, Sangmeshwer P. and Gaikwad, Abaji G.} } @article { ISI:000271812000007, title = {Studies of anion transport through supported liquid membrane}, journal = {Analytical Letters}, volume = {42}, number = {18}, year = {2009}, month = {NOV}, pages = {PII 916769949}, publisher = {TAYLOR \& FRANCIS INC}, address = {325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA}, abstract = {

Transport studies of anions were investigated through cellulose triacetate supported liquid membrane. The experimental variables explored were concentration of anions, sodium hydroxide, and stirring speed. The two-channel membrane system has been explored for the transport of carbonate ions from source to receiving phases. Carbonate ions are selectively transported through the cellulose triacetate supported liquid membrane in comparison with that of nitrate and sulfate. Sulfate and nitrate anions are strongly held in the cellulose triacetate membrane, and then stripped out later. Carbonate ions are loosely bound to the cellulose triacetate membrane and stripped out earlier.

}, keywords = {Anions, cellulose triacetate membrane, solvent effect, stability of supported liquid membrane, two-channel membrane system}, issn = {0003-2719}, doi = {10.1080/00032710903202063}, author = {Gaikwad, Abaji G.} } @article { ISI:000269792800010, title = {Studies on carbonate ion transport through supported liquid membrane using primene JMT and tributyl phosphate}, journal = {Separation Science and Technology}, volume = {44}, number = {11}, year = {2009}, month = {AUG}, pages = {2626-2644}, publisher = {TAYLOR \& FRANCIS INC}, address = {325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA}, abstract = {

A supported liquid membrane system consisting of source, receiving and membrane phases, in which mixed extractants were used in the membrane phase, was explored for the carbonate ion transport from source to receiving through membrane phase. Primary amine Primene JMT and TBP were used as extractants (carriers) in liquid membrane phase. Different experimental variables such as concentration of carbonate ion, carriers, alkali and hydrogen peroxide, stirring speed, etc have been investigated. Primary amine Primene JMT and TBP mixed carriers show the synergistic effect for the transport of carbonate ions through supported liquid membrane system. The stability of the supported liquid membrane system has been explored for 50 h. The pre-concentration of carbonate ions from dilute solutions were also demonstrated. The effect of different alkalis on the permeability coefficient of transport of carbonate ions through supported liquid membrane system has been investigated. The primary amine in combination with TBP shows more effective for the transport of carbonate ions through supported liquid membrane system in comparison with that of secondary and tertiary amines.

}, keywords = {carbonate ion, primary amine primene JMT, supported liquid membrane, synergistic effect, tributyl phosphate (TBP)}, issn = {0149-6395}, doi = {10.1080/01496390902886062}, author = {Gaikwad, Abaji G.} } @article { ISI:000270872200003, title = {Studies on transport of carbonate ions through a supported liquid membrane}, journal = {Chemical and Biochemical Engineering Quarterly}, volume = {23}, number = {3}, year = {2009}, month = {SEP}, pages = {267-275}, publisher = {CROATIAN SOC CHEMICAL ENGINEERING TECHNOLOGY}, address = {BERISLAVICEVA 6, PO BOX 123, HR-10000 ZAGREB, CROATIA}, abstract = {

The transport of carbonate ions through a supported liquid membrane in the presence and absence of carriers has been explored. The liquid membrane used was the combined liquid cation and anion exchangers in toluene immobilized in the porous polypropylene support. The permeability coefficient (P) of carbonate ions transport from the source to receiving through membrane phase has been estimated. The different experimental variables such as the concentration of carbonate ions in source phase, the concentration of Aliquat-336 (tricapryl(methyl)ammonium carbonate) and PC-88A (2-ethyl-hexyl phosphonic acid mono-2-ethylhexyl ester) in membrane phase, alkali metal hydroxide concentration in receiving phase, and the stirring speed of the Source phase and receiving phase have been explored. The stability of liquid membrane phase during the transport of carbonate ions from source phase to receiving phase was tested for 50 h. The enrichment factor for carbonate ion transport from the source to receiving phase was found to be higher at lower concentrations of carbonate ions in comparison with that of at higher concentrations. A model has been developed for the effective transport of carbonate ions through the cross section area of liquid membrane phase from source to receiving phase.

}, keywords = {alkali metal hydroxide, carbonate ions, liquid anion and cation exchangers, permeability coefficient, supported liquid membrane}, issn = {0352-9568}, author = {Gaikwad, Abaji G.} } @article { ISI:000275969800001, title = {Transport of yttrium metal ions through fibers supported liquid membrane solvent extraction}, journal = {Journal of Rare Earths}, volume = {28}, number = {1}, year = {2010}, month = {FEB}, pages = {1-6}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

A novel idea of transport of yttrium (III) metal ions through fibers supported liquid membrane in two stage processes namely source to membrane and membrane to receiving phase has been proposed. The fibers supported liquid membrane was impregnated with different concentrations carrier. The experimental variables explored were concentration of yttrium (III) ions, pH of source phase, PC-88A concentration in membrane phase, acid concentration in receiving phase and stirring speed. The pre-concentration of yttrium MO ions was investigated from the dilute solutions. The two-channel fibers supported liquid membrane solvent extraction was investigated for the transport of yttrium (III) ions from the source to membrane and membrane to receiving phase. The transport of yttrium (III) ions was observed through the fibers supported liquid membrane with capillary action.

}, keywords = {channel, extraction, fibers supported liquid membrane solvent extraction, PC-88A, rare earths, stripping, yttrium metal ion}, issn = {1002-0721}, doi = {10.1016/S1002-0721(09)60038-7}, author = {Gaikwad, Abaji G. and Rajput, A. M.} } @article { ISI:000286829500001, title = {Chromatographic separations of zinc, iron and copper metal ions through cellulose poroussolid fiber supported solid membrane in mixedsolvent systems}, journal = {Chemical Engineering Communications}, volume = {198}, number = {6}, year = {2011}, month = {JAN}, pages = {PII 932740676}, publisher = {TAYLOR \& FRANCIS INC}, address = {325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA}, abstract = {

An interesting aspect of chromatographic separation of zinc, iron, and copper metal ions through a cellulose porous solid fiber supported solid membrane from source solution to receiving phase has been explored in mixed solvent systems. The cellulose porous solid fiber supported solid membrane was prepared by chemically immobilizing tartaric acid. The experimental variables explored were concentration of copper, zinc, and iron metal ions, hydrochloric acid, composition of mixed solvents, and stirring speed. The efficiency of a cellulose porous solid fiber supported solid membrane system has been evaluated for the separation of metal ions. The pre-concentration of metal ions was carried out from the dilute solutions. The two-channel chromatographic cellulose porous solid fiber supported solid membrane system has been investigated for the transport of metal ions from the source solution to receiving phase. The capillary action phenomenon in the cellulose micro fibers plays a significant and active role in the transport of ions through the cellulose porous solid fiber supported solid membrane in mixed solvents.

}, keywords = {and iron ions: Single- and double-channel membrane system, Cellulose porous solid fiber supported solid membrane, Copper, zinc}, issn = {0098-6445}, doi = {10.1080/00986445.2011.534007}, author = {Gaikwad, Abaji G.} } @article { ISI:000293546100005, title = {Removal of metal ions from aqueous solution using trioctyl phosphine oxide-containing mixed solvents in conjunction with a fibre-supported solid membrane}, journal = {Adsorption Science \& Technology}, volume = {29}, number = {2}, year = {2011}, month = {JAN}, pages = {169-183}, publisher = {MULTI-SCIENCE PUBL CO LTD}, address = {5 WATES WAY, BRENTWOOD CM15 9TB, ESSEX, ENGLAND}, abstract = {

A novel method has been developed for the removal of mercury, arsenic and tin ions using a fibre-supported solid membrane placed between the source phase and the receiving phase which contained trioctyl phosphine oxide (TOPO) in a mixed solvent. The fibre-supported solid membrane was prepared by the esterification of cellulose fibre with tartaric acid at 120 degrees C. The experimental variables explored were the initial concentration of the metal ion (10(-2) to 10(-4) M) in the source phase, the type of mixed solvent employed [containing TOPO, TOPO + acetone, TOPO + tetrahydrofuran, TOPO + 1,4-dioxane, TOPO + methanol, TOPO + ethanol or TOPO + 2-propanol (20-80\% v/v)], the concentration of HCl (0.25-1 M) in the receiving phase and the stirring speed (50-130 rpm) of the bulk source and the receiving phase. The efficiency of the organic solvent in the mixed solvent followed the order: TOPO + tetrahydrofuran \> TOPO + 1,4-dioxane \> TOPO + acetone \> TOPO + 2-propanol \> TOPO + ethanol \> TOPO + methanol \> TOPO. The separation of the metal ions was discussed.

}, issn = {0263-6174}, author = {Gaikwad, Abaji G.} } @article { ISI:000293066000011, title = {Transport of carbonate ions through supported liquid membrane by using Alamine 336 and trioctylphosphine oxide as carriers}, journal = {Green Chemistry Letters and Reviews}, volume = {4}, number = {2}, year = {2011}, month = {MAR}, pages = {159-169}, publisher = {TAYLOR \& FRANCIS LTD}, address = {4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND}, abstract = {

Transport studies were carried out for carbonate ions through supported liquid membrane (SLMs) by sing Alamine 336 and trioctylphosphine oxide (TOPO) as carriers. Experimental variables were investigated, such as concentration of carbonate ion (10(-5) to 4 x 10(-2) M), carriers (10(-5) to 10(-1) M), and alkali (0.01-0.5); and stirring speed (50-50 rpm) of bulk solutions. The use of combined carriers Alamine 336 and TOPO shows a synergic transport of carbonate ions. The stability of the SLM system in relation to the transport of carbonate ions has been studied. The enrichment of carbonate ions (10(-6) to 4 x 10(-2) M) from the dilute solution was explored. The different combinations of amines with TOPO show synergic permeability of the carbonate ions through SLM system.

}, keywords = {Alamine 336, carbonate ion, supported liquid membrane, synergic effect, trioctyl phosphine oxide (TOPO)}, issn = {1751-8253}, doi = {10.1080/17518253.2010.528046}, author = {Gaikwad, Abaji G.} } @article { ISI:000299239000008, title = {Transport of indium, gallium and thallium metal ions through chromatographic fiber supported solid membrane in acetylacetone containing mixed solvents}, journal = {Chinese Journal of Chemical Engineering}, volume = {19}, number = {6}, year = {2011}, month = {DEC}, pages = {955-963}, publisher = {CHEMICAL INDUSTRY PRESS}, address = {NO. 3 HUIXINLI CHAOYANGQU, BEIJING 100029, PEOPLES R CHINA}, abstract = {

The transport of metal ions of indium, gallium and thallium from source solution to receiving phase through the chromatographic fiber supported solid membrane in the acetylacetone (HAA) containing mixed solvent system has been explored. The fibers supported solid membranes were prepared with chemical synthesis from cellulose fibers and citric acid with the carboxylic acid ion exchange groups introduced. The experimental variables, such as concentration of metal ions (10(-2) to 10(-4) mol.L(-1)) in the source solution, mixed solvent composition [for example, acetylacetone, (2,4-pentanedione), (HAA) 20\% (by volume), 1,4-dioxane 10\% to 60\% and HCl 0.25 to 2 mol.L(-1)] in the receiving phase and stirring speed (50-130 r.min(-1)) of the bulk source and receiving phase, were explored. The efficiency of mixed solvents for the transport of metal ions from the source to receiving phase through the fiber supported solid membrane was evaluated. The combined ion exchange solvent extraction (CIESE) was observed effective for the selective transport of thallium, indium and gallium metal ions through fiber supported solid membrane in mixed solvents. The oxonium salt formation in the receiving phase enhances thallium, indium and gallium metal ion transport through solid membrane phase. The selective transport of thallium metal ions from source phase was observed from indium and gallium metal ions in the presence of hydrochloric acid in organic solvents in receiving phase. The separation of thallium metal ions from the binary mixtures of Be(II), Ti(IV), Al(III), Ca(II), Mg(II), K (I), La(III) and Y(III) was carried out in the mixed solvent system using cellulose fiber supported solid membrane.

}, keywords = {acetylacetone, extraction, fiber supported solid membrane, metal ions transfer, stripping}, issn = {1004-9541}, author = {Gaikwad, Abaji G.} } @article { ISI:000300274300002, title = {Transport of metal ions through cellulose fiber supported solid membrane into tributyl phosphate containing mixed solvents}, journal = {Chemical and Biochemical Engineering Quarterly}, volume = {25}, number = {4}, year = {2011}, month = {DEC}, pages = {425-431}, publisher = {CROATIAN SOC CHEMICAL ENGINEERING TECHNOLOGY}, address = {BERISLAVICEVA 6, PO BOX 123, HR-10000 ZAGREB, CROATIA}, abstract = {

A novel cation exchange fiber supported solid membrane was developed for transport of cobalt, manganese and nickel metal ions. Fiber supported solid membrane was prepared by chemically modifying the cellulose fibers with citric acid. In the fiber supported solid membrane, the diffusion by capillary action by keeping the liquid phase in the porous solid fiber and ion exchange mechanism were used for the effective transport of metal ions. The experimental variables examined were concentration of metal ions (10(-2) to 10(-4) mol L-1) in the source solution, mixed solvent composition (phi = 20 \% TBP, acetone or tetrahydrofuran or 1,4-dioxane or methanol or ethanol or 2-propanol 10 to 60 \% and HCl (1 to 2 mol L-1) in the receiving phase and stirring speed (40-120 rpm) of the bulk source and receiving phase. The enrichment of concentration of cobalt, manganese and nickel metal ions was observed from the dilute solutions.

}, keywords = {binary of mixtures of metal ions, cobalt, extraction, fiber supported solid membrane, ion exchange, manganese and nickel metal ions, stripping}, issn = {0352-9568}, author = {Gaikwad, Abaji G.} } @article { ISI:000287903100004, title = {Transport of metal ions through fiber supported solid membranes in mixed solvents}, journal = {Fibers and Polymers}, volume = {12}, number = {1}, year = {2011}, month = {FEB}, pages = {21-28}, publisher = {KOREAN FIBER SOC}, address = {KOREA SCIENCE TECHNOLOGY CTR \#501 635-4 YEOGSAM-DONG, KANGNAM-GU, SEOUL 135-703, SOUTH KOREA}, abstract = {

The transport of metal ions has been explored of bismuth, cadmium and lead from source solution to receiving phase through the fiber supported solid membrane system. The fibers supported solid membranes were prepared by chemically modification of cellulose fibers with the introducing the ion exchanging groups. The experimental variables explored were concentration of metal ions in the source solution, mixed solvent composition in the receiving phase and stirring speed of the bulk source solution and receiving phase. The efficiency has been evaluated for the transport of metal ions from the source to receiving phase through the fiber supported solid membrane. The pre-concentration was investigated of metal ions from the dilute solutions. The fiber supported solid membrane with two-channel systems had been investigated for the transport of metal ions from the source to receiving phase. The capillary action phenomenon helps to effectively transport the metal ions through the fiber supported solid membrane.

}, keywords = {binary of mixtures of metal ions, Bismuth, Cadmium and lead metal ions, extraction, fiber supported solid membrane, ion exchange, stripping}, issn = {1229-9197}, doi = {10.1007/s12221-011-0021-8}, author = {Gaikwad, Abaji G.} } @article { ISI:000314145100008, title = {Behavior of the transport and separation of lanthanum, yttrium and lutetium metal ions through a celluose fiber supported solid membrane}, journal = {Macedonian Journal of Chemistry and Chemical Engineering}, volume = {31}, number = {2}, year = {2012}, month = {Jan}, pages = {255-269}, publisher = {SOC CHEMISTS TECHNOLOGISTS MADECONIA}, type = {Article}, address = {STS CYRIL \& METHODIUS UNIV, FAC TECHNOL \& METALLURGY, PO BOX 560, RUGER BOSKOVIC 16, SKOPJE, MK-1001, MACEDONIA}, abstract = {

A newly designed membrane cell was used to study the behavior of the transport and separation of lanthanum, yttrium and lutetium metal ions using a cellulose fiber supported solid membrane. The cellulose fiber membrane was prepared by the chemical modification of cellulose fiber using an esterification reaction with citric acid. Different experimental variables were investigated, such as time, membrane size, stirring of the source and receiving phases and the pH of the source phase. The use of different stripping agents in the receiving phase was explored, including nitric acid, hydrochloric acid, sodium nitrate, ammonium thiocyanate, D(2)EHPA, TBP, Aliquat-336, tartaric acid, EDTA and organic solvents. Pre-concentration of lanthanum, yttrium and lutetium metal ions from dilute solutions was carried out.

}, keywords = {binary mixture, cellulose fiber membrane, Citric acid, complexing reagent, Lanthanum, lutetium, metal ions, Separation, transport studies, yttrium}, issn = {1857-5552}, author = {Gaikwad, Abaji G.} } @article { ISI:000314801600002, title = {Preparation and characterization of calcium silicate for CO2 sorption}, journal = {Adsorption Science \& Technology}, volume = {30}, number = {10}, year = {2012}, month = {DEC}, pages = {817-830}, publisher = {MULTI-SCIENCE PUBL CO LTD}, address = {5 WATES WAY, BRENTWOOD CM15 9TB, ESSEX, ENGLAND}, abstract = {

An attempt has been made to develop different samples of calcium silicate and to screen these samples for CO2 sorption and alkalinity in order to achieve maximum CO2 sorption. The CO2 sorption capacity of these samples was examined at different temperatures. Various methods such as solid-solid fusion, sol-gel, molten salt and templates (CTAB, cetyltrimethylammonium bromide or Aliquat 336, tricaprylmethylammonium chloride) were used to prepare the calcium silicate samples. The solid mass of calcium silicate samples were obtained by calcining the solid product obtained in an atmosphere of air or helium at 900 degrees C for 3 hours. The calcium silicate samples were characterized for surface area, alkalinity, scanning electron microscopic images and X-ray diffraction patterns. The temperature profile of CO2 sorption by calcium silicate was studied in the temperature range of 40-850 degrees C. Our results showed that the alkalinity and surface area of calcium silicate were in the range from 2.35 to 20 mmol g(-1) and 1.4 to 10 m(2) g(-1), respectively. The sorption of CO2 at 500 degrees C over calcium silicate for the different Ca/Si mol ratio (range: 1-6) was found to be in the range from 3.12 to 29.96 wt\%. Addition of a promoter such as sodium, potassium, caesium and lanthanum was found to enhance the sorption of CO2 by calcium silicate. Several samples of different mol ratios of Ca/Si prepared by different methods were tested for the sorption of CO2 at 500 degrees C.

}, issn = {0263-6174}, doi = {10.1260/0263-6174.30.10.817}, author = {Kale, Kishor B. and Raskar, Reshma Y. and Rane, Vilash H. and Gaikwad, Abaji G.} } @article { ISI:000321665000007, title = {Applications of lithium zirconium silicate at high temperature for the carbon dioxide sorption and conversion to syn-gas}, journal = {Water Air and Soil Pollution}, volume = {224}, number = {6}, year = {2013}, month = {JUN}, pages = {1569}, publisher = {SPRINGER}, address = {VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS}, abstract = {

The applications of different samples of lithium zirconium silicate contributing to CO2 sorption and conversion of CO2 to syn-gas at high temperatures were investigated. Several samples of lithium zirconium silicate prepared by solid-solid fusion method were calcined in air or nitrogen atmosphere at 900 degrees C for 3 h. The lithium zirconium silicate samples were characterized by acidity/alkalinity, surface area, XRD pattern, SEM images, and CO2 sorption. The alkalinity and surface area of the samples of lithium zirconium silicate were found to be in the range of 15.1 to 20.0 mmol g(-1) and 0.05 to 2.13 m(2) g(-1), respectively. The temperature profile of CO2 sorption by samples of lithium zirconium silicate was given for the range 100 to 700 degrees C. The CO2 sorption was found to be in the range of 12.81 to 18.04 wt.\% at 550 degrees C for samples of lithium zirconium silicate with different Li/Zr/Si mole ratios from 1 to 6. The crystalline phases in the samples of the lithium zirconium silicate, Li6Si2O7, ZrSiO4, Li2SiO3, Li2ZrO3, Li4ZrO4, and Li4SiO4 could contribute to CO2 capture. The conversion of CO2 by methane to syn-gas over the lithium silicate samples and PdO (5 wt.\%)/Al2O3 at 500 degrees C with the gas hourly space velocities 6,000, 12,000, and 36,000 mL h(-1) g(-1) of methane and 6,000 mL h(-1) g(-1) of CO2 was explored. However, the higher conversion of CO2 to syn-gas was observed at the low gas hourly space velocity of 6,000 mL h(-1) g(-1) of methane.

}, keywords = {Applications of lithium zirconium silicate, CO2 sorption, Solid-solid fusion method, Syn-gas, Temperature profile}, issn = {0049-6979}, doi = {10.1007/s11270-013-1569-2}, author = {Raskar, Reshma and Rane, Vilas and Gaikwad, Abaji G.} } @article { ISI:000343747200015, title = {Removal of carbonate ion through cellulose fiber supported solid membrane}, journal = {Journal of Engineered Fibers and Fabrics}, volume = {9}, number = {2}, year = {2014}, month = {JAN}, pages = {120-126}, publisher = {INDA}, type = {Article}, address = {PO BOX 1288, CARY, NC 27512-1288 USA}, abstract = {

A novel fiber supported solid membrane was prepared by chemical modification of cellulose fiber with tartaric acid, 8-hydroxyquinoline and magnesium carbonate for removal of bicarbonate ion. Loading effect of tartaric acid, magnesium metal ion and 8-hydroxyquinoline over cellulose fiber was studied for removal of carbonate ion. The selective removal of carbonate, sulfate, phosphate, and nitrate ions through fiber supported solid membrane was investigated. The removal of carbonate ion with/without bubbling of CO2 was determined in source and receiving phases.

}, issn = {1558-9250}, author = {Gaikwad, Abaji G.} }