Separation of Red (Y_2O_3:Eu^(3+)), Blue (BaMgAl_(10)O_(17):Eu^(2+)) and Green (CeMgAl_(10)O_(17):Tb^3) Rare Earth Phosphors by Liquid/Liquid Extraction

A novel process for separation of red （Y2O3：Eu^3＋）, blue（BaMgAl10O17：Eu^2＋） and green （CeMgAl10O17：Tb^3） rare earth fluorescent powders was proposed. At first, the blue powder can be extracted selectively from an aqueous solution using a chelating collector 2-thenoyltrifluoroacetone （TTA） dissolved in heptane at alkaline pH condition, then, chloroform was used for extracting the green powder into organic phase. The red phosphor remains in aqueous phase with potassium sodium tartrate depressant （PST）. Therefore, three phosphors can be separated successfully from their artificial mixtures by liquid/liquid extraction, and grades and recovery of separated products reach respectively as follows： red is 96.9% and 95.2%, blue is 82.7% and 98.8%, green is 94.6% and 82.6%.

Determination of brominated diphenyl ethers in atmospheric particulate matter using selective pressurized liquid extraction and gas chromatography–mass spectrometry with a negative chemical ionization

This study describes the development and validation of a sensitive and reliable method for determination of polybrominated diphenyl ethers（PBDEs）in atmospheric particulate matter using selective pressurized liquid extraction（SPLE）and gas chromatography–mass spectrometry with a negative chemical ionization（GC-NCI-MS）.Extraction and clean-up were performed using PLE with 2 g florisil and 3 g silica placed in the extraction cells.Under optimal conditions,14 PBDEs were extracted at 70℃ using hexane/dichloromethane（50：50,v/v）as solvent.Validation of SPLE returned excellent recoveries for most analytes,with relative standard deviations mostly below20%.Method detection limits ranged from 0.13 to15.38 ng·mL^-1 for the GC-MS analyses.The method was successfully applied to atmospheric particulate matter of Beijing,where analytes were detected in the range of182.79 to 468.99 pg·m^-3.

Synthesis of 2, 6 Bis(1′-Phenyl- 3′- Methyl-5′-Oxopyrazole- 4′) Pyridinediacyl and Its Solid Liquid Extraction Behavior for Ce(Ⅲ)

diketone type chelating ligands have high coordinative activity and selectivity, and are widely applied in analytical chemistry. In order to obtain profounder understanding to the properties of bis(4 acylpyrazolone 5), A new 4 acylpyrazol 5 one derivative (H 2BPMPP) was syntheszed, which contains a heterocyclic ring between two 1 phenyl 3 methyl 4 acylpyrazol 5 one rings. The new compound was characterized by element analyses, UV, IR and 1H NMR spectra. The equilibrium of the keto enol tautomerism was studied. The results show that a lower dielectric constant of solvent favors the enol form which has a higher λ max . Due to special merits of paraffin wax, the solid liquid extraction behavior of Ce(Ⅲ) with molten paraffin wax as a diluent was also investigated at higher temperature. The value of the pH 1/2 was 3.19 and the value of log K ex was 3.467. The chemical composition of the complex was obtained by the slope analysis method.

Comparison of conventional and supported liquid extraction methods for the determination of sitagliptin and simvastatin in rat plasma by LC-ESI-MS/MS

Three extraction methods were compared for their efficiency to analyze sitagliptin and simvastatin in rat plasma by LC-MS/MS, including （1） liquid-liquid extraction （LLE）, （2） solid phase extraction （SPE） and （3） supported liquid extraction （SLE）. Comparison of recoveries of analytes with different extraction methods revealed that SLE was the best extraction method. The detection was facilitated with ion trap-mass spectrometer by multiple reactions monitoring （MRM） in a positive ion mode with ESI. The transitions monitored were m./z 441.1→325.2 for simvastatin, 408.2→235.1 for sitagliptin and 278.1→260.1 for the IS. The lower limit of quantification （LLOQ） was 0.2 ng/mL for sitagliptin and 0.1 ng/mL for simvastatin. The effective SLE offers enhanced chromatographic selectivity, thus facilitating the potential utility of the method for routine analysis of biological samples along with pharmacokinetic studies.

Efficient desulfurization of gasoline fuel using ionic liquid extraction as a complementary process to adsorptive desulfurization

The extractive desulfurization of a model gaso- line containing several alkyl thiols and aromatic thiophenic compounds was investigated using two imidazolium-based ionic liquids （ILs）, 1-butyl-3-methylimidazolium tetrachloroaluminate, and 1-octyl-3-methylimidazolium te- trafluoroborate, as extractants. A fractional factorial design of experiments was employed to evaluate the effects and possible interactions of several process variables. Analysis of variance tests indicated that the number of extraction steps and the IL/gasoline volume ratio were of statistically highly significant, but none of the interactions were significant. The results showed that the desulfurization efficiency of the model gasoline by the ILs could reach 95.2 % under the optimal conditions. The optimized conditions were applied to study the extraction of thiophenic compounds in model gasoline and several real gasoline samples; the following order was observed in their separation： benzothio- phenc 〉 thiophcne 〉 3-methylthiophene 〉 2-methylthiophene, with 96.1% removal efficiency for benzothiophene. The IL extraction was successfully applied as a complementary process to the adsorptive desulfurization with acti- vated Raney nickel and acetonitrile solvent. The results indicated that the adsorptive process combined with IL extraction could provide high efficiency and selectivity, which can be regarded as a promising energy efficient desulfurization strategy for production of low-sulfur gasoline.

Design, Optimization and Control of Extractive Distillation for Separation of Ethyl Acetate-Ethanol-Water Mixture Using Ionic Liquids

In this work, the process simulation of pressure-swing distillation(PSD) and extractive distillation(ED) using ionic liquid(IL) 1-butyl-3-methylimidazolium acetate([bmim][OAc]) as the entrainer for separation of ethyl acetateethanol-water mixture is performed. The design parameters of the two distillation processes are optimized with the minimum total annual cost(TAC) serving as the objective function. The results show that the TAC saving of ED process is 35.27% in comparison with that of PSD process in the case of achieving the same purity and yield of ethyl acetate.In addition, the dynamic controllability of ED process is further studied. The traditional two-point temperature control structure is proposed for the ED process, and it works pretty well while taking into account the disturbances in both feed rate and feed composition.

A highly sensitive SPE-liquid/liquid extraction-RPLC analytical method for the determination of 6β-hydroxycortisol and cortisol in cancer patients' urine

A highly sensitive SPE-liquid/liquid extraction RPLC method has been developed for the analysis of 6β-hydroxycortisol and cortisol in the urine of cancer patients. Methods： After SPE column purification and liquid-liquid extraction, the sample test solutions were analyzed with RPLC using a C18 analytical column. This improved analytical method has been validated for linearity, accuracy （recovery from urine）, repeatability （within-day and between-day precision）, specificity, sensitivity, and stability. This SPE-liquid/liquid extraction-RPLC is rapid, simple, accurate and reproducible. The technique is particularly useful for monitoring the CYP3A activity of cancer patients in clinical settings. The results are expressed as the ratio of 6β-hydroxycortisol to cortisol. Results： The CYP3A activity from a total of 153 samples was measured using this improved method. Considerable variation in the CYP3A activity of different cancer patients has been documented. Thus, personalized medical treatment based on the individual metabolic enzyme activity level is necessary. Conclusion： This new analytical method facilitates such individualized medical treatments.

Direct injection HILIC-MS/MS analysis of darunavir in rat plasma applying supported liquid extraction

A novel bioanalytical method was developed and validated for the quantitative determination of darunavir（DRV） in rat plasma by employing hydrophilic interaction chromatography and tandem mass spectrometry（HILIC-MS/MS） with supported liquid extraction（SLE）.lrbesartan（IRB） was used as an internal standard（IS）.The analyte in rat plasma（200 μL） was isolated through SLE using ethyl acetate as the eluting solvent.The chromatographic separation was achieved on Luna-HILIC（250 mm × 4.6 mm,5 μm）column with a mobile phase of 0.1% of formic acid in water：acetonitrile（5：95,v/v）,at a constant flow rate of 1.0mL/min.The MS/MS ion transitions for DRV（548.1→392.0） and IS（429.2→207.1） were monitored on an ion trap mass spectrometer,operating in the multiple reaction monitoring（MRM） mode.The lower limit of quantitation（LLOQ） was 0.2 ng/mL and quantitation range was 0.2-5000 ng/mL.The method was validated for its selectivity,sensitivity,carryover,linearity,precision,accuracy,recovery,matrix effect and stability.The method was successfully applied to pharmacokinetic study in rats.

Simultaneous Determination of Bisphenols and Alkylphenols in Water by Solid Phase Extraction and Ultra Performance Liquid Chromatography-tandem Mass Spectrometry

To establish an analytical method for determination of four bisphenols （BPA, BPB, BPF, and BPS） and two alkylphenols （4-n-OP, 4-n-NP） in water by ultra performance liquid chromatography- tandem mass spectrometry （UPLC/MS/MS）. The water samples were extracted and condensed with solid-phase extraction （SPE） using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0μg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%.

Separation of Red (Y_2O_3: Eu^(3+)), Blue (Sr,Ca,Ba)_(10)(PO_4)_6Cl_2: Eu^(2+) and Green (LaPO_4:Tb^(3+),Ce^(3+)) Rare Earth Phosphors by Liquid/Liquid Extraction

A novel process for separation of red （Y2O3： Eu^3＋）, blue （Sr, Ca, Ba）10（PO4）6Cl2： Eu^2＋ and green （LaPO4： Tb^3＋, Ce^3＋） fine tricolor phosphor powders was established. First, the green phosphor was extracted and separated from three phosphor mixtures in heptane/DMF（N, N-Dimethylformamide） system using stearylamine or laurylamine （DDA） as the cationic surfactant. Then, after being treated with 99.5% ethanol, the blue and red phosphors could be separated in Heptane/DMF system in presence of 1-octanesulfonic acid sodium salt as the anionic surfactant. Satisfactory separation results have been achieved through two steps extractions with their artificial mixtures. The grades and recovery of separated products reached respectively as follows： red product was 95.3% and 90.9%, blue product was 90.0% and 95.2%, and green product was 92.2% and 91.8%.

Effect of alkali extraction on pit membranes and liquid uptake of four commercial softwoods

The present study examined the effect of alkali extraction on pit membranes （PMs） and liquid uptake of four conifers. Af- ter alkali extraction, the deposits around the PMs almost dissolved in Cunninghamia lanceolata Hook. and Cryptomeriajaponica D. Don wood which showed good liquid uptake. In contrast, in Larix leptolepis Gordon and Pseudotsuga menziesii Franco, although the tori adhered strongly to the pit aperture preventing liquid transportation, the liquid uptake of the woods improved markedly. More- over, the combined treatment of alkali extraction-transverse compression had no synergistic effect in improving liquid uptake. These results demonstrate that alkali extraction is effective in improving the liquid uptake of wood.

Extraction of Copper from Waste Solution Using Liquid Emulsion Membrane

The extraction of copper from acidic medium using Liquid Emulsion Membrane LEM as contactors was studied. b diketone LIX 54 as an extractant ,sesqueoleate which is nonionic surfactant with HLB value 3.7 and 0.1 M H2SO4 as stripping solution were used. The influence of initial concentration of copper in the aqueous feed phase, pH of external and internal aqueous phase, stirring speed, and concentration of extractant on the extraction rate was examined. The results obtained showed that practically all the copper content was removed from the acidic feed solution. The recovery of copper attained 96–100% and concentration ratios of about 40-fold could be achieved.

Extraction and Enrichment of Copper by Liquid Emulsion Membrane Using LIX 664N

Process intensification using liquid emulsion membranes (LEMs) for extraction of copper has been studied in this work. In LEM process the extraction and stripping processes are combined in one stage. The solubility of the solute or the chemical affinity between the solute and carrier reagent in the membrane results in the separation of the solute from the feed mixture. In this work the membrane phase comprised of LIX 664N as the extractant dissolved in kerosene and Span 80 as surfactant. The stripping phase was sulfuric acid with 180 g/l concentration and feed phase had copper concentration of 3.5 g/l. Effect of various process parameters such as batch contact time, speed of agitation, W:O ratio and treat ratio has been experimentally investigated to get better insight of the process. The maximum enrichment of copper in the internal phase obtained was 11.6 times with batch contact time of 10 minutes, agitation speed of 300 rpm and treat ratio of 6:1.

Colorimetric determination of nanomolar concentrations of silicate in natural waters after liquid-liquid extraction using methyl isobutyl ketone

A sensitive solvent extraction method for the determination of nonamolar concentrations of silicate in natural waters is developed. According to the traditional aqueous silicate method, silicomolybdenum blue formed by the reaction between silicate and ammoni- um molydate and reduced by metol-sulfite reagent is extracted by methyl isobutyl ketone. The absorbance can be enhanced substantially up to 10-folds. The detection limit of silicate is 8 nmol/dm^3 , which is one tenth smaller than the traditional method, with the precision of 4.0% at a silicate level of 50 nmol/dm^3 and 3.2% at a silicate level of 6 μmol/dm^3. Comparing the calibration curves in the distilled water and seawater, it can be seen that the salt effect also exists in the extraction method. However, the salt effect is a linear function of the salinity and can be corrected by simple calibration. The proposed method is successfully applied to the determination of silicate in natural waters. Natural concentrations of arsenate, arsenite and phosphate cause negligible interference.

Extraction Kinetics of Lanthanum in Chloride Medium by Bifunctional Ionic Liquid [A336][CA-12] Using a Constant Interfacial Cell with Laminar Flow

The extraction kinetics of La(III) from aqueous chloride solutions into n-heptane solutions of bifunctional ionic liquid extractant [A336][CA-12](tricaprylmethylammonium sec-octylphenoxy acetic acid) was investigated using a constant interfacial cell with laminar flow. The effects of stirring speed, temperature and specific interfacial area on the extraction rate were examined. The results indicate that mass transfer kinetics of La(III) is a mixed-controlled process influenced by interfacial reaction. On the basis of mass transfer kinetic results in the extraction of La(III) by [A336][CA-12], the extraction rate equation of La(III) is proposed in terms of pseudo-firstorder constants, which is supported by the measured thermodynamic equations. The mass-transfer kinetic model deduced from the rate controlling step is adequate to interpret the experimental data qualitatively.

Separation of ^(152+154)Eu,^(90)Sr from radioactive waste effluent using liquid–liquid extraction by polyglycerol phthalate

A new polyglycerol phthalate extractant was prepared and characterized using Fourier transform infrared spectroscopy, proton nuclear magnetic resonance(~1H NMR) spectroscopy, and thermogravimetric analysis. A preliminary study of the extraction of long-lived(^(90) Sr and ^(152+154)Eu) and short-lived(^(90) Y) radionuclides by polyglycerol phthalate was performed. The influence of different diluents, concentration of the acid, type of acid, and various interfering ions was explored. The stripping of ^(152+154)Eu radionuclide was studied by using different acid solutions, and it was found that sulfuric acid was the ideal acid for this purpose. Furthermore,^(152+154)Eu was extracted from the fission products(^(90) Sr) and the extraction% of^(90) Sr was found to improve in the presence of interfering ions.

Isolation and purification of carbazole contained in anthracene slag by extraction combined with medium pressure liquid chromatography

Ultrasonic-assisted extraction(UAE)combined with medium pressure liquid chromatography(MPLC)was designed for carbazole separation from anthracene slag(AS).The effects of liquid/solid ratio,temperature,and extraction times on carbazole separation were investigated.When using CC14 and ethyl acetate as extraction solvents and combining with MPLC,carbazole recovery and purity are 75.1%and 95.4%,respectively.The mechanism for carbazole separation were presumed by examining intermolecular interactions such as N-H…π,π-π,and C-Cl…πinteractions.These results demonstrate that UAE/MPLC has a considerable potential as a green and promising strategy for separating and purifying carbazole and other chemicals from AS.

Extraction Behavior of Rare Earths with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 Using Solid-liquid Extraction Technique

The extraction behavior of rare earths was studied by using paraffin with ceresin as a diluent containing 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5.In solid phase,the composition of complexes is REP_3.The equilib- rium extraction constants and pH_(1/2) values of solid-liquid extraction are higher than those of normal liquid-liquid extraction.The extraction efficiency tends to maximum when the ratio of phases is 1:1.When the extraction temperature is higher than the melting point of paraffin and the extraction time is over 10 min,the extraction efficiency keeps constant.Moreover,the relationship among separation factor,equilibrium extrac- tion constant,pH_(1/2) value and atomic number was obtained.The mechanism of solid-liquid extraction is analogous to that of liquid-liquid extraction.

Preparation of Highly Concentrated Silver Nanoparticles in Reverse Micelles of Sucrose Fatty Acid Esters through Solid-Liquid Extraction Method

Silver nanoparticles were synthesized in reverse micelles consisting of sucrose fatty acid esters by dissolving reactant powder in the water pool of reverse micelles through the solid-liquid extraction. Silver nanoparticles having various sizes and shapes were obtained at high concentration. The size of silver nanoparticles was controlled by reaction temperature. Moreover, the size of silver nanoparticles was dependent upon the average esterification degree of sucrose fatty acid esters forming reverse micelles. The wavelength in the peaks, which corresponded upon the localized surface plasmon resonance of resultant silver nanoparticles, was correlated with their sizes.

Determination of the Flavonoids from Ginkgo Biloba Extract by High Performance Liquid Chromatography

HPLC method for analysis of the flavonoids from ginkgo biloba extract (GBE) was studied. By suitable selection of columns. symmetrical chromatographic peaks were obtained without using acidic modifier in the mobile phase, which can eliminate the time for cleaning the chromatographic system and simplify the analystic method for GBE Experimental conditions: column: Hypersil BDS C-18, 5mumx4x250 mm: column temperature: 35degreesC; mobile phase: 46% methanol-54% water; flow rate: 0.7 mL/min; detection wavelength: 360nm.