Combination Of Solvent Extraction Research Articles

Quantitative Analysis of Lactone Enantiomers in Butter and Margarine through the Combination of Solvent Extraction and Enantioselective Gas Chromatography-Mass Spectrometry.

We quantified the enantiomeric distributions of δ- and γ-lactones in butter, fermented butter, and margarine through the combination of solvent extraction and enantioselective gas chromatography-mass spectrometry. The main lactones in butter and fermented butter comprised (R)-δ-decalactone, (R)-δ-dodecalactone, (R)-δ-tetradecalactone, (R)-δ-hexadecalactone, and (R)-γ-dodecalactone. In contrast, margarine samples consisted of only δ-decalactone and δ-dodecalactone in racemic forms, indicating that synthetic aroma chemicals were added to margarine. After heat treatment, 13 types of lactones were detected in butter and fermented butter. In heated butter and fermented butter, major δ-lactones in the (R)-form were abundant, but only δ-octalactone in the (S)-form was detected. In contrast, γ-dodecalactone (main γ-lactone in the heated samples) was abundant in the (R)-form, whereas other γ-lactones were detected in the racemic form. These results suggested that the major lactones in dairy products are in the (R)-form. Furthermore, the heat treatment affected the enantiomeric distribution of lactones in butter and fermented butter.

Combination of solvent extraction with deep eutectic solvent based dispersive liquid-liquid microextraction for the analysis of aflatoxin M1 in cheese samples using response surface methodology optimization.

A new extraction procedure based on combination of a solvent extraction and deep eutectic solvent based dispersive liquid-liquid microextraction has been introduced for the extraction of aflatoxin M1 from cheese samples. In this method, acetonitrile, deionized water, and n-hexane are added onto the sample and vortexed. Owning to different affinities of the substances in cheese toward the mentioned solvents, an efficient and selective extraction of the analyte is done in the acetonitrile phase. After centrifugation, the acetonitrile phase is removed and mixed with a new hydrophobic deep eutectic solvent prepared from N,N-diethanol ammonium chloride and carvacrol as an extraction solvent. The mixture is injected into deionized water, and a cloudy solution is obtained. Eventually, an aliquot of the organic phase is injected into high-performance liquid chromatography-fluorescence detection. After optimizing the effective parameters with the response surface methodology and a quadratic model, limits of detection and quantification were 0.74 and 2.56ng/kg, respectively. The obtained extraction recovery and enrichment factor were 94% and 94, respectively. Also, intra- (n=6) and interday (n=4) precisions were less than or equal to 8.6% at a concentration of 5ng/kg. The suggested method was applied to determine aflatoxin M1 in different cheese samples.

Insight into the structure of polystyrene-poly(methyl methacrylate) core-shell particles synthesized by seeded suspension polymerization

Core-shell particles were synthesized employing seeded suspension polymerization. Suspension polystyrene (PS) particles were used as seeds, and poly(methyl methacrylate) (PMMA) was synthesized in the presence of polystyrene seeds. A combination of solvent extraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy techniques were employed to study the structure and morphology of synthesized particles. The results suggested a core-inner shell-outer shell structure for the synthesized particles in which the PS core was covered by a PMMA-rich inner shell and a very thin PS-rich outer shell. The size and concentration of PMMA domains decreased from the outer shell toward the core of the particle, and particle morphology was mainly controlled by the limitations to the diffusion of MMA through the polymer particle.

Characterization of lactones in Wagyu (Japanese beef) and imported beef by combining solvent extraction and gas chromatography–mass spectrometry

The lactone content of Wagyu beef and imported beef in Japan was estimated using a combination of solvent extraction and gas chromatography–tandem quadrupole mass spectrometry. This method revealed that the total lactone content was higher in Wagyu than in the imported beef. The most abundant lactone in the Wagyu and imported beef was δ-hexadecalactone, followed by δ-tetradecalactone, δ-dodecalactone, and δ-decalactone. The total lactone content in the Wagyu and imported beef increased approximately twofold or threefold when the extracted fats from the beef were heated. In addition, the raw beef was heated under actual cooking conditions, such as boiling at 80 °C for 2 min and roasting at 180 °C for 30 s, and found with the increased amounts of lactones. The results showed that the cooking processes increased the lactone content in the Wagyu and imported beef, and the change in the lactone content was greater in the roasted beef than in the boiled beef. These results suggest that considerable amounts of lactone precursors remain in the raw beef.

PROCESSING OF A METAL CONCENTRATE FROM GROUND WASTE PRINTED CIRCUIT BOARDS IN ACIDIC MEDIA USING HYDROGEN PEROXIDE AS OXIDANT

The recovery of precious and base metals of a metal concentrate from ground waste printed circuit boards (PCBs) is described in detail. Samples were treated with NaOHaq. to remove the soldering mask. Experiments were performed in acidic medium (HF, H2SO4, CH3COOH or H3PO4) using H2O2 as oxidant. Base metals were leached in high yields (>99 wt.%) at ~40 oC after ~1 h (HF), ~2 h (H2SO4), ~4 h (H3PO4) and ~5 h (CH3COOH). Lead precipitated in the presence of H2SO4 and HF. Precious metals were not oxidized. Ceramic/fiberglass components were dissolved in the presence of HF. Silver, palladium and gold were recovered from the insoluble solid, in this order, by a sequential oxidative treatment in aqueous medium. Recovery of leached elements was possible by a combination of solvent extraction and precipitation. The choice of the extractant and the precipitant were essential to recover them with high yields. The leachates from H3PO4 + H2O2 experiments could not be processed above pH 2.5. Leaching of waste PCBs in the presence of a weak organic acid is possible but a multistage separation scheme for elements recovery is unavoidable as PCBs is a complex material in terms of composition.

Optimization of Pre-treatment Method in Shikimic Acid Extraction from Palm Oil Mill Effluent (POME)

The global pandemic spread of influenza like bird flu and swine flu are forcing abigger production of anti-influenza drug called Oseltamivir phosphate. The drug is made by synthesizing a compound named shikimic acid. Although the demand of the drug increases, the source of shikimic acid material is limited. Meanwhile, palm oil mill effluent (POME), a waste generated from palm oil industry is provenly rich in phytonutrients. This research aims to improve the shikimic extraction process from palm oil mill effluent by pre-treating the POME. Three pre-treatments were done on the POME which are solvent-extraction method, sedimentation method, and combination of solvent-extraction and sedimentation method. Sedimentation used the centrifugal principle and solvent-extraction used n-hexane as the solvent. Extraction of shikimic acid from pre-treated POME was done using ethyl acetate as the solvent. Detection of shikimic acid was done using TLC method and FT-IR instrument, while HPLC was used to measure the amount of shikimic acid extracted. Yield of shikimic acid obtained after solvent-extraction pre-treatment (0.0795%) was better than the sedimentation pre-treatment (0.015%). Also, the solvent-extraction pre-treatment was more efficient (87.51%) than sedimentation pre-treatment (68.15%) in removing oil and grease. However, the best result was produced from the combination of both pre-treatments.

Size Exclusion Coupled to Reversed Phase Liquid Chromatography for the Characterization of Cranberry Products

A combination of solvent extraction, size exclusion purification, and reversed-phase liquid chromatography with UV absorption and fluorescence detection was here used for the determination of flavan-3-ols and related oligomeric compounds in cranberry products. The method relied on robust, simple, and inexpensive instrumental equipment present in most of routine analytical laboratories. Sample extracts in methanol/water/hydrochloric acid solution (60:39:1, v/v/v) were subjected to size-exclusion chromatography (SEC) using Sephadex LH-20 as the sorbent to separate simple phenolic and oligomeric components. As a novel aspect of this work, the implementation of the SEC process in a reusable packed column was practically and economically highly advantageous. Fractions were analyzed by reversed-phase chromatography using a C18 core-shell analytical column and 0.1% formic acid aqueous solution and methanol as the components of the mobile phase. Chromatograms were recorded by UV absorption spectroscopy at 280 nm and by fluorescence spectroscopy at λex 280 nm/λem 347 nm. The method was applied to the determination of flavan-3-ols in various cranberry samples. Catechin, epicatechin, and procyanidins A2 and B2 were found in different amounts depending on the cranberry varieties.

Recovery of base metals, silicon and fluoride ions from mobile phone printed circuit boards after leaching with hydrogen fluoride and hydrogen peroxide mixtures

The recovery of copper, nickel, zinc, silicon, iron, aluminum, tin and fluoride ions from fluoride leach liquors of non-ground printed circuit boards (PCBs) from mobile phones is described in detail. These PCBs were leached with HF + H2O2 mixtures after previous treatment with 6 mol L−1 NaOH (removal of the solder mask). A combination of solvent extraction (SX) and precipitation techniques was used. 99.5 wt% zinc, copper and nickel, in this order, were extracted in one stage (Zn, Ni) or two stages (Cu) with di-2-ethylhexylphosphoric acid (D2EHPA) diluted in kerosene (25 °C, A/O = 1 v/v) after adjusting the pH of the leachate. They were easily stripped by aqueous H2SO4. Iron, aluminum and tin did not interfere because they were masked by fluoride ions. Iron and aluminum were precipitated together as Na3FeF6 + Na3AlF6 by careful addition of aqueous NaOH. Silicon, tin and fluoride ions were recovered together (Na2SiF6 + Na2SnF6 + NaF) by careful evaporation of the aqueous solution after SX of nickel. The tin salt was leached from this solid by absolute ethanol. High HF concentration (10 mol L−1) in the leachant affected SX of Cu(II) and precipitation of iron/aluminum flurocomplexes since some NaF partially precipitated at acidic pH.

Debinding and Sintering of an Injection-Moulded Hypereutectic Al⁻Si Alloy.

Hypereutectic Al–Si (20 wt.%) alloy parts were fabricated by employing a powder injection moulding (PIM) technique with a developed multi-component binder system composed of high-density polyethylene (35 wt.%), carnauba wax (62 wt.%) and stearic acid (3 wt.%). The feedstocks contained 83 wt.% metal powders. The debinding process was carried out by a combination of solvent extraction and thermal decomposition. The effects of solvent debinding variables such as kind of solvents, debinding temperatures and time, and the bulk surface area to volume ratios on the debinding process were investigated. Thermal debinding and the subsequent sintering process were carried out in a heating sequence under a nitrogen atmosphere. The influences of sintering temperature and sintering time on the mechanical properties and structure were considered. Under the optimal sintering condition, sintering at 550 °C for 3 h, the final sintering parts were free of distortion and exhibited good mechanical properties. Relative sintered density, Brinell hardness, and tensile strength were ~95.5%, 58 HBW and ~154, respectively.

Novel Multifunctional Mesoporous Microsphere with High Surface Area for Removal of Zinc Ion from Aqueous Solution: Preparation and Characterization

Amino-functionalized magnetic mesoporous microsphere has been successfully synthesized through a two-step coating process of silica on a magnetic core (Fe3O4). In the synthesis process, cetyltrimethyl ammoniumbromide (CTAB) was used as a structure-directing agent and it was removed by combination of solvent extraction and calcination modified processes. In this method, mesoporous silica shell with higher surface area was formed which could facilitate the loading of much more amino groups and the capacity to adsorb more heavy metal ions such as Zn2+ was provided. Different amounts of 3-aminopropyl triethoxysilane (APTES) were examined in order to obtain an optimum amount of amino groups which can be grafted on Fe3O4/SiO2/meso-SiO2 microsphere. The resultant multifunctional microsphere was characterized by field emission scanning electron microscope, transmission electron microscope, FTIR spectrophotometer, X-ray diffraction, vibration sample magnetometer, thermogravimetric analysis, nitrogen adsorption–desorption and particle size analyzer. Comparing to functionalized amino group on traditional magnetic mesoporous silica, the as-prepared microsphere not only exhibited higher specific surface area (617.31 m2 g−1) but also demonstrated higher adsorption capacity for Zn(II) (270.2703 mg g−1 at 25 °C). Important of all, the adsorbent was simply removed from sample solution by magnetic field and it was regenerated by acid treatment. Synthetic route of Fe3O4/SiO2/meso-SiO2–NH2 and its use for Zn(II) ions removal.

Production of Essention Oil from Tobacco Leaves for Insect Repellents

The production of essential oil from tobacco leaves for insect repellents using a combination of solvent extraction was investigated. Tobacco essential oil is generally different from other essential oils, which usually consist of several special aroma compounds. The tobacco essential oil and solvent extracts were analyzed by gas chromatography with a mass spectrometer (GC–MS). Tobacco essential oils are concentrated odorous substances. Nicotine is present as a major substance and found only trace amounts of the essential oils. Nicotine is an insecticide that affects to insects. This research showed that a development of products forms tobacco leaves and environmentally. This product evaporated pass through a packaging made from luffa gourd. The luffa gourd is a natural packaging can be easily degradation in the environment. Moreover, this product also helped to reduce the hazardous chemicals or pesticides usage in agricultural activities and not residues in the environment for long times.

Characterization of the Potent Odorants Contributing to the Characteristic Aroma of Matcha by Gas Chromatography-Olfactometry Techniques.

The odorants contributing to the characteristic aroma of matcha were investigated by analysis of the headspace samples and the volatile fractions prepared by a combination of solvent extraction and the SAFE techniques using three matcha powders of different grades (high, medium, and low). Gas chromatography-olfactometry of the headspace samples (GCO-H) and aroma extract dilution analysis (AEDA) applied to the volatile fractions revealed 16 (FD factor ≥1) and 39 (FD factor ≥43) odor-active peaks, respectively. Among them, 14 and 37 of the odorants, most of which were newly detected in matcha, were identified or tentatively identified by GC-MS and GC-O, respectively. By comparing the perceived odorants of three matcha powders, it was revealed that eight compounds with sweet, green, metallic, and floral notes showed high flavor dilution (FD) factors irrespective of the grades. In addition, some odorants were suggested to influence the characteristic aroma of each grade. Furthermore, trans-4,5-epoxy-(E)-2-decenal, one of the potent odorants of matcha, was revealed to exist as a racemic mixture in matcha. This result suggested that trans-4,5-epoxy-(E)-2-decenal is formed by a nonenzymatic reaction in matcha, different from that in black tea, and that the unique manufacturing process of matcha has a close connection with its formation.

Chemical composition and structure characterization of distillation residues of middle-temperature coal tar

Abstract The distillation residues of middle-temperature coal tar (DRMCT) were separated into saturate, aromatic, resin and asphaltene fractions by using the combination of solvent extraction and column chromatography separation. The isolated four fractions have been further characterized through the combination of elemental analysis, Fourier transform infrared (FTIR) spectra, proton nuclear magnetic resonance spectrum ( 1 H NMR) and molecular weight analysis. The analysis results confirm the view that the saturate fraction from DRMCT was mainly composed of long-chain alkanes and almost all of the heteroatoms (S, N and O) were existed in aromatic structures. The asphaltene fraction had the highest molecular weight, the most amount of heteroatom (especially oxygen) and was the most condensed with shortest alkyl side chains among all the fractions. In addition, for the heavier components, the resin and asphaltene fractions from DRMCT contained lower ratio of H/C, lower molecular weight and higher aromaticity degree when compared with crude oils.

DEACIDIFICATION OF PALM OIL USING SOLVENT EXTRACTION INTEGRATED WITH MEMBRANE TECHNOLOGY

In this work, the efficiency of crude palm oil (CPO) deacidification using solvent extraction integrated with membrane technology is studied. Different solvents including ethanol, hexane and methanol were selected to extract the palmitic acid from model fatty system in the model fatty system to solvent ratio of 1:2. Experimental results showed that ethanol was the best solvent to extract palmitic acid from the model fatty system, recording about 65.5% fatty acid reduction in the model fatty system. Three commercial solvent resistant nanofiltration (SRNF) membranes (SolSep NF010206, NF030306, and NF030705) were then selected to examine their respective performance in recovering ethanol from palmitic acid-rich ethanol solvent. The results revealed that the combination of solvent extraction and membrane technology is remarkable simple and waste-free approach to overcome major drawbacks of conventional refinery operation.

Extraction of phenolics from broom branches using green technologies

AbstractBACKGROUNDThe effective exploitation of plants as a biorenewable resource has very important significance for sustainable development. Broom (Cytisus scoparius) has been used and associated with healthy benefits in the Iberian Peninsula for a long time. With this in mind, different technologies, alone or in combination, have been proposed to obtain valuable compounds from broom branches.RESULTSComposition showed a seasonal variation. Periods that lead to higher content of extractives were selected to design a combined autohydrolysis and supercritical CO2 extraction process for the production of antioxidants. The autohydrolysis process leads to higher yields than conventional solvent extraction and SC–CO2 extraction produced a raffinate with radical scavenging capacity comparable with ethanolic extracts. The major bioactive compounds identified in extracts were flavonoids, phenolic acids and phenolic aldehydes.CONCLUSIONSAn extraction process resulting from a combination of solvent extraction and autohydrolysis increased the extraction yields and the recovery of extracts containing bioactive compounds suitable for use in food, cosmetic and pharmaceutical applications. The knowledge gained from this study should be helpful to further exploit and apply this resource. © 2016 Society of Chemical Industry

Recovery of Vanadium from H2SO4-HF Acidic Leaching Solution of Black Shale by Solvent Extraction and Precipitation

The recovery of vanadium from sulfuric and hydrofluoric mixed acid solutions generated by the direct leaching of black shale was investigated using solvent extraction and precipitation methods. The process consisted of reduction, solvent extraction, and stripping, followed by precipitation and calcination to yield vanadium pentoxide. The influence of various operating parameters on the extraction and recovery of vanadium was studied. Vanadium (IV) was selectively extracted using a mixture of 10% (v/v) di(2-ethylhexyl)phosphoric acid and 5% (v/v) tri-n-butylphosphate in sulfonated kerosene. Using six extraction and five stripping stages, the extraction efficiency for vanadium was 96.7% and the stripping efficiency was 99.7%. V2O5 with a purity of 99.52% was obtained by oxidation of the loaded strip solution and precipitation of ammonium polyvanadate at pH 1.8 to 2.2, followed by calcination of the dried precipitate at 550 °C for 2 h. It was concluded that the combination of solvent extraction and precipitation is an efficient method for the recovery of vanadium from a multi-element leach solution generated from black shale.

Using real particulate matter to evaluate combustion catalysts for direct regeneration of diesel soot filters

The particulate produced by internal combustion engines has a complex composition that includes a large proportion of porous soot within which condensed and adsorbed organic molecules are trapped. However, many studies of the catalytic combustion of particulate are based on the assumption that commercially produced carbon can be used as a reliable mimic of engine soot. Here we show that soot removed from a diesel particulate filter is rich in the polyaromatic molecules that are the precursors of the solid particulate. Through a combination of solvent extraction and evolved gas analysis, we have been able to track the release and transformation of these molecules in the absence and presence of combustion catalysts. Our results reveal that, although the rate of combustion of the elemental carbon in diesel soot is higher than that of graphite, deep oxidation of the polyaromatic molecules is a more demanding reaction. An active and stable Ag–K catalyst lowers the combustion temperature for elemental carbon by >200°C, but has little effect on the condensed polyaromatic molecules. The addition of a secondary catalyst component, with aromatic-oxidation functionality is required to target these molecules. Although the combined catalyst would not enable a completely passive regeneration system for diesel passenger cars, it would improve the efficiency of existing active systems by reducing the amount of fuel-injection required for trap regeneration.

The Treatment of Waste Metal Cutting Fluid by Extraction and Adsorption Process

A novel recovery process of the effective ingredient from the waste metal cutting fluid was proposed by the combination of solvent extraction and solid adsorption technique. The influence factors such as the volume fraction of 1-butanol, the ratio of solvent to oil, the quantities of KOH and the extraction temperature were studied through experiments. The results show that: The maximum quality of oil sludge was obtained when added 3g KOH to waste liquid(200ml).The mass of oil sludge was found to increase with the increase of solvent to oil ratio until it reached the maximum at the ratio of 3:1.

Characterisation of soot in oil from a gasoline direct injection engine using Transmission Electron Microscopy

In this work, an investigation of soot-in-oil samples drawn from the oil sump of a gasoline direct injection (GDI) engine was carried out. Soot particulate was characterised in terms of size, distribution and shape of the agglomerates, and internal structure of the primary particles. The test engine was a 1.6l modern light-duty EURO IV engine operated at speed between 1600 and 3700rev/min, and torque between 30 and 120Nm. After a double oil-flushing procedure the engine was operated for 30h. Oil samples were drawn from the sump and prepared for Transmission Electron Microscopy (TEM) and High resolution TEM analysis (HRTEM) by a combination of solvent extraction, centrifugation and diethyl ether bathing. Soot agglomerates were measured in terms of their skeleton length and width, and fractal dimension. The mean skeleton length and width were 153nm and 59nm respectively. The fractal dimension was calculated using an iterative method and the mean value was found to be 1.44. The primary particles were found to be spherical in shape with some irregularities and presented an average diameter of 36nm with a mode of 32nm and standard deviation of 13nm. The majority of particles showed an inner core and outer shell similar to diesel soot, although an amorphous layer was also clearly visible.

Remediation of DDTr contaminated soil by the combination of solvent extraction and catalytic hydrodechlorination

A combination technique for remediation of DDT and its metabolites (DDTr) contaminated soil based on successive steps of solvent extraction, followed by catalytic hydrodechlorination (HDC) was studied.