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1.
Extraction of cottonseed oil using subcritical water technology   总被引:1,自引:0,他引:1  
This work represents the extraction of cottonseed oil using subcritical water. The extraction efficiencies of different range temperatures (180–280°C), having mean particle size range from 3 mm to less than 0.5 mm, water:seed ratios of 0.5:1, 1:1, and 2:1, and extraction times in the range of 5–60 min were all investigated. The composition of the extracted oil, using the subcritical water, was analyzed by gas‐liquid chromatography and compared with that extracted using traditional hexane extraction. The results showed that the optimum temperature, mean particle size, water:seed ratio, and extraction time were 270°C, <0.5 mm, 2:1, and 30 min, respectively. In addition the extracted oil was identical to that extracted using the traditional hexane method. © 2010 American Institute of Chemical Engineers AIChE J, 2011  相似文献   

2.
Papaya seed is a good source of edible oil with considerable antioxidant activity. Here, papaya seed oil (PSO) of Hainan/Eksotika variety was obtained by subcritical butane extraction (SBE) and supercritical carbon dioxide extraction (SCDE), and its yields, physicochemical properties, oxidative and thermal stability, and chemical and microscopic structures were compared. The results showed that SBE‐PSO had a higher yield (25.88 ± 0.29% vs. 19.47 ± 0.92%), but a lower melting point compared to SCDE‐PSO. Molecular structures indicated that there was no oxidative degradation during SBE and SCDE. Both SBE and SCDE caused significant structural changes of seed tissues. In addition, aldehyde composition analysis using high performance liquid chromatography (HPLC) showed that SBE‐PSO had fewer octanal, nonanal, 2‐decenal, and 2‐undecenal contents than SCDE‐PSO. All these results proved that SBE‐PSO exhibited superiority on the oxidative stability compared to SCDE‐PSO. It indicated that SBE was a superior method to obtain antioxidant edible oil with good stability.  相似文献   

3.
Sorghum has potential as a domestic source of wax for applications in the food and nonfood industries. The waxes extracted from sorghum have similar physical properties to those of Carnauba wax, a common imported commercial wax. This work focused on the extraction, fractionation, and characterization of waxes from sorghum kernels. Extraction was performed by varying the extraction conditions including temperature and solvents (hexane, ethanol, and methanol). A fractionation technique was developed to separate and quantify waxes from nonwaxes. The fractions were then characterized using a reverse‐phase high‐performance liquid chromatography method developed in our laboratory that utilizes an evaporative light‐scattering detector for quantification. The results showed that the average amount of wax extracted from the surface of intact sorghum kernels was about 0.3 wt% using hexane at temperatures between 25 and 120°C and 1000 psi. The yield of wax via hexane extraction increased with temperature and ranged from about 0.06 to 0.39 wt%. Extraction with alcohols resulted in higher yields of extracts, but after fractionation to remove nonwax components, the yield of waxes was reduced by 31% for ethanol and 47% for methanol compared to hexane.  相似文献   

4.
采用索氏提取法提取水浸预处理后的五味子中的木脂素,考察了虹吸次数、液固比、颗粒粒径及乙醇浓度对萃取率的影响,采用响应面法进行优化. 结果表明,五味子醇甲的最佳提取条件为:乙醇浓度98.05%(j),液固比67.20 mL/g,颗粒平均粒度0.33 mm,该条件下理论萃取率为80.90%,实际萃取率为77.17%;五味子甲素的最佳提取条件为:乙醇浓度96.38%(j),液固比72.52 mL/g,颗粒平均粒度0.21 mm,该条件下五味子甲素理论萃取率为77.11%,实际萃取率为74.31%;五味子乙素的提取最佳条件为:乙醇浓度96.38%(j),液固比72.52 mL/g,颗粒平均粒度0.21 mm,该条件下理论萃取率为77.13%,实际萃取率为74.23%. 各因素对木脂素提取率影响的显著性顺序为乙醇浓度>液固比>颗粒粒径.  相似文献   

5.
Countercurrent two-stage extraction and cream demulsification were fully integrated and demonstrated on laboratory scale (2 kg soybeans) wherein the enzyme used for demulsifying the cream was used in the extraction steps of enzyme-assisted aqueous extraction processing (EAEP). Protease enzyme (Protex 6L) entered the integrated EAEP process in the demulsification step and the skim, which contained the enzyme, resulting from breaking the cream emulsion was recycled upstream into the second extraction stage and then to the first extraction stage. Oil, protein and solids extraction yields of 96.1 ± 1.4%, 89.3 ± 1.0%, and 81.2 ± 2.0%, respectively, were achieved with steady-state operation of integrated EAEP. Higher degrees of protein hydrolysis (DH) were obtained when using the integrated process compared with the process when not recycling the enzyme. Higher extents of hydrolysis probably increased emulsion formation thereby affecting lipid distribution among the fractions. Overall free oil recovery was reduced due to more oil shifting to the skim fraction.  相似文献   

6.
Proof-of-concept for integrated, countercurrent, two-stage, enzyme-assisted aqueous extraction processing of soybeans was demonstrated on a pilot-plant scale (75 kg extruded flaked soybeans) where the protease used to demulsify the cream was recycled into upstream extraction stages. Oil, protein, and solids extraction yields of 98.0 ± 0.5%, 96.5 ± 0.4%, and 86.8 ± 0.5% were achieved by using the integrated countercurrent process. A three-phase horizontal decanter centrifuge efficiently separated the solids from the two liquid fractions (skim and cream). Fine separation between the two liquid fractions was important to reducing the volume of skim contaminating the cream fraction, thereby reducing the amount of enzyme used for cream demulsification and subsequent extraction. We were able to reduce enzyme use when moving from the laboratory to the pilot-plant scale, which reduced the degree of protein hydrolysis and improved cream demulsification. Enzyme-catalyzed cream demulsification was 91.6% efficient and 93.0% free oil recovery from cream was achieved by using the integrated approach.  相似文献   

7.
A new method combining cloud point extraction (CPE) with dispersive liquid–liquid microextraction (DLLME) named “cloud point‐dispersive liquid–liquid microextraction (CP‐DLLME)” was presented in this work for the first time for the determination of organic acids as model compounds in biological samples using high performance liquid chromatography and UV detection (HPLC–UV). Water (disperser solvent) containing tert‐octylphenol ethoxylate (7.5EO) as extraction solvent, was rapidly injected into a warmed sample solution and cloudy state formed immediately. After that, phase separation was performed by centrifugation. The surfactant‐rich phase was diluted with acetonitrile and injected into a HPLC–UV apparatus. The influence of several important parameters on the extraction efficiencies was evaluated. Under optimized experimental conditions, the calibration graphs were linear in the range of 0.06–1,500 µg L?1 for target analytes. Coefficient of determination (r2) ranged from 0.9985 to 0.9994. The limits of detection were in the range of 0.05–17.1 µg L?1. The new method was successfully applied with satisfactory results for analysis of target analytes in spiked samples. The relative mean recoveries of the spiked samples ranged from 91.8 to 107.1 % with relative standard deviations in the range of 2.1 to 4.3 %.  相似文献   

8.
《分离科学与技术》2012,47(10):1510-1517
A 17-run Box-Behnken design (BBD) with three factors was used to improve the conditions for extracting astaxanthin from shrimp waste. The astaxanthin level was determined by high performance liquid chromatography (HPLC) using a C18 column and a UV detector at 476 nm. The mean extraction yield of astaxanthin at the improved conditions (extraction time 1.4 h, extraction temperature 72.4°C, and liquid-solid ratio 27.3) was 98.7 ± 2.6 µg g?1. A solid-phase extraction (SPE)-HPLC method was developed with a new hybrid organic-inorganic hybrid monolith for further purification of astaxanthin from shrimp waste. The SPE recoveries were ranging from 81.3 ± 2.4% to 86.5 ± 3.3%, and the intra-day and inter-day relative standard deviations (RSDs) of the proposed method were less than 4.3 ± 0.5% and 4.8 ± 0.2%, respectively. BBD increased the extraction efficiency and shortened extraction times significantly. SPE-HPLC with hybrid monolith showed good selectivity and purified astaxanthin from shrimp waste.  相似文献   

9.
超临界CO2萃取玉米胚芽油工艺的研究   总被引:9,自引:0,他引:9  
本文研究采用超临界CO2从玉米胚芽中萃取油品的工艺条件,运用响应面法探讨了萃取压力、萃取温度和物料粒径在油品产率为90%时对CO2消耗量的影响,确定了最佳工艺参数,分析比较了超临界CO2萃取、正己烷索氏萃取和压榨三种方法对油品质量和脂肪酸组成的影响。  相似文献   

10.
An ethanol-assisted aqueous enzymatic extraction was performed for peony seed oil (content of 30%). This method included cooking pretreatment, pectinase hydrolysis, and aqueous ethanol extraction, and the corresponding variables in each step were investigated. The changes in viscosity and dextrose equivalent values of the reaction medium as a function of changing enzymatic hydrolysis time were compared to the oil yield. The microstructures of peony seeds were analyzed using confocal laser scanning microscopy to understand the process of oil release as a result of cooking and grinding. The highest oil yield of 92.06% was obtained when peony seeds were cooked in deionized water with a solid–liquid ratio of 1:5 (w/v) at 110°C for 1 hour, ground to 31.29 μm particle size, treated with 0.15% (w/w) pectinase (temperature 50°C, pH 4.5, time 1 hour), and then extracted with 30% (v/v) aqueous ethanol (temperature 60°C, pH 9.0, time 1 hour). After processing with pectinase followed by ethanol extraction, the residual oil content in water and sediment phase decreased to 5% and 3%, respectively. The quality of the oil obtained by ethanol-assisted aqueous enzymatic extraction was good, complying with the Chinese standard.  相似文献   

11.
In this work, a combination of sonication and carbon dioxide expanded liquid extraction (SA‐CXLE) is used for the first time for the extraction of lipids from berry seeds. Three solvents (ethanol, methanol and ethyl lactate) are screened for the best recoveries of total lipids. Ethanol is selected due to its efficiency, greenness and sustainability. The effects of operation variables including temperature, time and CO2 molar fraction on extraction performance are examined using a response surface methodology. The optimum conditions were found at 0.37 molar fraction of CO2 in ethanol, a temperature of 52 °C and an extraction time of 7 min for two cycles. The SA‐CXLE method extracts 323 ± 38 mg g?1 seed compared to 194 ± 23 using a conventional solid‐liquid extraction. SA‐CXLE is successfully applied to profile lipids from gooseberry, blackcurrant, chokeberry, red currant, and rowanberry seeds. More than 17 lipid classes are characterized and identified. Gooseberry shows the highest amount of oil of 352 mg g?1 seed. Practical Applications: The developed method provides a fast, efficient and simple approach to extract and profile lipids using a combination of green solvents. Total lipid content and fatty acids composition of the berry seeds are essential information in pharmaceutical, cosmetic, food and nutritional applications.  相似文献   

12.
Precipitation of nanoparticles is applied in various fields with a rising interest in the formulation of poorly soluble drugs. The impact of fluid mixing on the precipitation of organic nanoparticles is analyzed. Direct numerical simulations are applied to determine the spatiotemporal evolution of the liquid phase composition and to estimate the particle evolution along Langragian trajectories. The simulation results are compared with laboratory experiments of mixing and particle size evolution, which use a recently developed approach to rapidly stabilize the precipitated nanoparticles. The impact of mixing on precipitation is revealed, thereby enabling a parameter‐free estimation of the mean particle sizes and the particle size distributions. The distributions of residence time, supersaturation time, and particle size are self‐similar for Reynolds numbers in the turbulent regime and allow the derivation of scale‐up rules.  相似文献   

13.
Bioactive components, asiatic acid and asiaticoside, were extracted from Centella asiatica using subcritical water as an extraction solvent. Extraction yields of asiatic acid and asiaticoside were measured using high-performance liquid chromatography (HPLC) at temperatures from 100 to 250 °C and pressures from 10 to 40 MPa. As temperature or pressure increased, the extraction yield of asiatic acid and asiaticoside increased. At the optimal extraction conditions of 40 MPa and 250 °C, the extraction yield of asiatic acid was 7.8 mg/g and the extraction yield of asiaticoside was 10.0 mg/g. Extracted asiatic acid and asiaticoside could be collected from water as particles with a simple filtering process. Dynamic light scattering (DLS) was used to characterize particle size. Particles containing asiatic acid were larger (1.21 μm) than particles containing asiaticoside (0.76 μm). The extraction yields of asiatic acid and asiaticoside using subcritical water at 40 MPa and 250 °C were higher than extraction yields using conventional liquid solvent extraction with methanol or ethanol at room temperature while the subcritical water extraction yields were lower than extraction yields with methanol or ethanol at its boiling point temperature.  相似文献   

14.
The present study presents experimental results concerning the supercritical CO2 extraction of essential oil from Algerian rosemary leaves. The effects of key operating parameters such as pressure, temperature, particle size and CO2 mass flow rate on the extraction yield were investigated. The obtained yields were in the range of 0.95–3.52 g oil/g dry rosemary, and the best value was observed at a pressure of 22 MPa, a temperature of 40 °C, a flow rate of 7 g/min, and a particle size of 1 mm. The performance of the local rosemary used was assessed by comparison of the obtained yields with values reported in the literature for essential oils derived from different rosemary sources. The GC and the GC‐MS analyses showed that the major compound detected in the essential oil was camphor, at 48.89 wt %.  相似文献   

15.
H. Uslu  I. Inci 《化学工程与技术》2009,32(12):1951-1957
The extraction of glutaric acid was studied using tridodecyl amine (TDA) with respect to the functional groups of the diluent. The diluents studied were 1‐octanol (alcohol), methyl isobuthyl ketone, MIBK (ketone), and toluene (aromatic hydrocarbon) and these were used to dilute the TDA. The experimental results of batch extraction experiments are reported as distribution coefficients, DC, loading factors, Z, and extraction efficiency, E. All measurements were carried out at 298.15 K. The results of the liquid‐liquid equilibrium measurements are correlated by a linear solvation energy relationship (LSER) model that takes into account physical interactions and modified Freundlich and Langmuir equations. The experimental results are compared with model results.  相似文献   

16.
S. Yuan  Y. Shi  H. Yin  Z. Chen  J. Zhou 《化学工程与技术》2012,35(10):1810-1816
Experiments were designed to ascertain the main factors for the Sauter mean drop size (d32) of the dispersed phase in a three‐stage modified Scheibel extraction column with no mass transfer. A precise correlation applied to the liquid‐liquid systems with low interfacial surface tension was proposed for calculating d32. The maximum relative error for all data was 16.0 % and the mean relative error ±4.6 %.  相似文献   

17.
This paper investigates the fundamental fire properties of surrogate refuse‐derived fuels (RDF), a class of multicomponent materials characterized by high void fraction, with particles of polydisperse sizes and significant internal porosity. A surrogate RDF was developed to improve the reproducibility of experimental measurements. This surrogate RDF reflects typical municipal solid waste collected in the city of Newcastle, in the state of New South Wales in Australia. The material consists of shredded newspaper, wood, grass and plastic bags, with small amounts of sugar and bread. About 95% of the material passes through 50 mm square screens, as required by ASTM E828 standard for RDF‐3 specification. The experiments presented in this paper were performed with the components of the RDF dried in a forced‐air oven at 103° C, except for grass which was dried under nitrogen. The material was found to be very hygroscopic, requiring special care in handling. The experiments performed in the cone calorimeter were designed to measure the heat release rate, total heat release, time to ignition, time to extinction, effective heat of combustion and formation of CO during the combustion process, as a function of sample thickness, sample density and the magnitude of the imposed radiative heat flux. The thermophysical properties of the surrogate material were either measured (solid density, void space, particle density, particle porosity) or extracted from the published data (heat capacity). The present surrogate RDF material was found to ignite easily, within a few seconds of the imposition of the incident heat flux of 40 kW m?2, and then to reach rapidly the peak heat release rate of 110–165 kW m?2. The deduced values of the critical heat flux, pyrolysis temperature and effective thermal conductivity are 9–10 (±2) kW m?2, 280–310 (±30)° C, and 0.4–0.7 (±0.3) W m?1 K?1, respectively, depending on the material density. The effective heat of combustion of the RDF was estimated as 15.3 MJ kg?1. The material produced 1 kg of CO per 18 kg of dried RDF, mostly during smouldering phase after the extinguishment of the flaming combustion. These results indicate that dried RDF pose significant fire risks, requiring that fire safety systems be implemented in facilities handling RDF. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

18.
Raschig Super‐Rings are well‐established in the field of rectification and absorption. Instead, the efficiency of these packings in liquid‐liquid extraction was not investigated till now. The application of Raschig Super‐Ring No. 0.3 and Raschig Super‐Ring No. 1 packings in unpulsed liquid‐liquid extraction columns of diameters DN 80 and DN 150 is investigated with respect to flooding point and efficiency. As a comparative study, 15‐mm and 25‐mm Pall‐Ring packings are used. The hydrodynamic studies indicate that the Raschig Super‐Ring offers a 9–10 % higher load capacity compared to the Pall‐Rings. In addition, the mass transport investigations performed using the test system toluene/acetone/water reveal that the height of transfer units (HTU) for the Raschig Super‐Ring No. 0.3 is higher than for the comparable 15‐mm Pall‐Ring. On average, the achieved difference of the HTU unit is 0.26 m.  相似文献   

19.
Extraction of rice brain oil using supercritical carbon dioxide and propane   总被引:1,自引:0,他引:1  
Extraction of rice bran lipids was performed using supercritical carbon dioxide (SC−CO2) and liquid propane. To provide a basis for extraction efficiency, accelerated solvent extraction with hexane was performed at 100°C and 10.34 MPa. Extraction pressure was varied for propane and SC−CO2 extractions. Also, the role of temperature in SC−CO2 extraction efficiency was investigated at 45,65, and 85°C. For the SC−CO2 experiments, extraction efficiencies were proportional to pressure and inversely proportional to temperature, and the maximal yield of oil achieved using SC−CO2 was 0.222±0.013 kg of oil extracted per kg of rice bran for conditions of 45°C and 35 MPa. The maximal yield achieved with propane was 0.224±0.016 kg of oil per kg of rice bran at 0.76 MPa and ambient temperature. The maximum extraction efficiencies of both SC−CO2 and propane were found to be significantly different from the hexane extraction baseline yield, which was 0.261±0.005 kg oil extracted per kg of rice bran. A simulated economic analysis was performed on the possibility of using SC−CO2 and propane extraction technologies to remove oil from rice bran generated in Mississippi. Although the economic analysis was based on the maximal extraction efficiency for each technology, neither process resulted in a positive rate of return on investment.  相似文献   

20.
BACKGROUND: Microorganisms have often been considered for the production of oils and fats as an alternative to agricultural and animal resources. Extraction experiments were performed using a strain of the yeast Yarrowia lipolytica (Y. lipolytica), a high‐lipid‐content yeast. Three different methods were tested: Soxhlet extraction, accelerated solvent extraction (ASE) and supercritical carbon dioxide (SCCO2) extraction using ethanol as a co‐solvent. Also, high pressure solubility measurements in the systems ‘CO2 + yeast oil’ and ‘CO2 + ethanol + yeast oil’ were carried out. RESULTS: The solubility experiments determined that, at the conditions of the supercritical extractor (40 °C and 20 MPa), a maximum concentration of 10 mg of yeast oil per g of solvent can be expected in pure CO2. 10% w/w of ethanol in the solvent mixture increased this value to almost 15 mg of yeast oil per g of solvent. Different pretreatments were necessary to obtain satisfactory yields in the extraction experiments. The Soxhlet and the ASE method were not able to complete the lipid extraction. The ‘SCCO2 + ethanol’ extraction curves revealed the influence of the different pretreatments on the extraction mechanism. CONCLUSION: Evaluating the effectiveness of a given pretreatment, ASE reduced the amount of material and solvent used compared with Soxhlet. In all three cases, the best total extraction performance was obtained for the ethanol‐macerated yeast (EtM). Addition of ethanol to the solvent mixture enhanced the oil solubility. Oil can be extracted from Y. lipolytica in two different steps: a non‐selective ethanol extraction followed by TAG‐selective SCCO2 purification. © 2012 Society of Chemical Industry  相似文献   

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