Extraction of pomegranate seed oil using subcritical propane and supercritical carbon dioxide

Extraction of oil from pomegranate seeds as a waste product of the juice industry using supercritical carbon dioxide and subcritical propane was studied in this work. The influence of the main operating conditions of extraction, namely, the temperature and pressure of extraction on the oil extraction yield and the correspondent fatty acid profile were analyzed and reported here. Soxhlet extraction with n-hexane was done for comparison with supercritical extraction resulting in a maximum yield of oil of 22.31 wt %. Supercritical carbon dioxide and subcritical propane extracted up to 58.53% (corresponding to maximum yield of 13.06 wt %) and 76.73% (corresponding to maximum yield of 17.12 wt %) of the total amount of pomegranate seed oil as measured using Soxhlet extraction, respectively. Results indicated that the subcritical propane is a suitable and selective solvent for the extraction of the pomegranate seed oil in function of smaller times and pressures employed compared to carbon dioxide extraction. The fatty acid composition of the extracted oil showed the presence of fatty acids of C₁₆, C₁₈, C₂₀, C₂₂, and C₂₄ carbon chains. Punicic (C_18.3) was the major fatty acids and comprise up to 70% of the total fatty acid content of the extracted oil among all samples. Finally, Lack??s plug flow model as developed by Sovova was applied to both extraction systems and a good agreement with the experimental results was obtained.     

A green separation process for recovery of healthy oil from pumpkin seed

In this study, pumpkin seeds, called as “Ürgüp Sivrisi” and grown in Cappadocia region, were used as plant materials because of high aroma contents. In the supercritical fluid extraction of pumpkin seed oil, the effect of main process parameters as the particle size (250-2360 μm), the volumetric flow rate of supercritical solvent (0.06-0.30 L/h), the operating pressure (20-50 MPa), the operating temperature (40-70 °C), the type of entrainer (ethanol and n-hexane) and those concentrations (0-10 vol.%) on the extraction yield, the oil solubility and the initial extraction rate were investigated. A cross-over effect for the extraction of pumpkin seed oil using supercritical CO₂ was determined at the operating pressure of 20-30 MPa. The maximum extraction yield obtained with entrainer free was reached 0.50 g oil/g dry seed at 600-1180 μm, 0.12 L/h, 50 MPa and 70 °C for the operation time of 5 h. The maximum extraction yield obtained with ethanol as an entrainer in the experiments was reached 0.54 g oil/g dry seed at the conditions of 600-1180 μm, 0.12 L/h, 30 MPa, 40 °C and 8 vol.% for the operating time of 2 h. The oil compositions were determined by gas chromatography analysis and the results showed that the compositions of pumpkin seed oil which were obtained by means of organic solvent extraction and supercritical fluid extraction were similar. The average oil compositions determined as 9.3 (±0.43)% palmitic acid, 7.5 (±0.6)% stearic acid, 32.3 (±0.6)% oleic acid, 48.1 (±0.6)% linoleic acid and 0.7 (±0.3)% linolenic acid. The morphological changes in the seeds were determined by the scanning electron microscopy analysis.     

Extraction of sunflower oil with supercritical CO2: Experiments and modeling

Extraction of sunflower oil from sunflower seeds (Heliantus annuus L.) using supercritical CO₂ was studied. The shrinking core model was applied to the modeling of the packed-bed extraction process. The experimental data were obtained for extraction conducted at the pressures of 20, 30, 40, 50 and 60 MPa; the temperatures of 313, 333 and 353 K, the CO₂ flow rates of 1–4, and 6 cm³ CO₂ min⁻¹; the mean particle diameters of 0.23, 0.55, 1.09, 2.18 mm. The supercritical CO₂ extraction process was modeled by a quasi steady state model as a function of extraction time, pressure, temperature, CO₂ flow rate, and particle diameter. The supercritical CO₂ extraction process. The intraparticle diffusion coefficient (effective diffusivity) D_e was used as adjustable parameter. The model using the best fit of D_e was correlated the data satisfactorily.     

超临界CO2萃取芹菜籽油工艺研究

以芹菜籽为原料,采用粉碎预处理后超临界CO2萃取的方法从蔓荆子中萃取芹菜籽油.考察了萃取时间、萃取温度及萃取压力对芹菜籽油收率的影响,并采用响应面法建立了芹菜籽油收率与萃取时间、萃取温度及萃取压力之间的关系,得到了最佳萃取工艺条件：萃取温度为30.4℃、萃取时间为80min,萃取压力20.02MPa,此时蔓荆子油的得率达到极值4.47％.该方法具有收率高、产品纯度高、污染小、节约能源的特点.     

超临界二氧化碳萃取枸杞籽油的实验研究与数值模拟

建立了一套超临界流体萃取枸杞籽油的实验流程。以二氧化碳为萃取剂,考察了萃取压力、操作温度、二氧化碳流量及原料颗粒度等因素对枸杞籽油萃取率的影响。确定了较佳的萃取工艺条件:压力30MPa,温度313～318K,枸杞籽颗粒40～50目,二氧化碳流量0.3～0.4m3/h时枸杞籽油萃取率最高,可达15.5%。基于萃取器微分单元和固态颗粒微分单元质量守恒原理,建立了微分方程,利用直线推动力近似理论拟合总传质推动力及平衡吸收常数,化简方程,对部分实验结果进行数值模拟。     

Extraction of jojoba oil with liquid CO2 + propane solvent mixtures

In this work liquid CO₂/propane mixtures were used to extract jojoba oil from oilseeds. First, experiments at 313 K and pressures of 70 bar and 200 bars were carried out on jojoba oil deposited on glass spheres, using different solvent concentrations (30 wt%, 50 wt% and 70 wt% CO₂), to assess the influence of the solvent composition and phase behavior on the extraction rate. Then, jojoba oil was extracted from the milled seeds under homogeneous liquid conditions, using solvent mixtures containing 30 wt% and 50 wt% CO₂ at 70 bar and 313 K. A solvent mixture with 30 wt% CO₂ exhibited good solvent power. Oil extraction yields of 98% were obtained using a minimum solvent to oilseed mass ratio of 5 g solvent/g oilseed and operating the extractor at 313 K and 70 bar.     

Modeling and optimization of process parameters for supercritical CO2 extraction of Argemone mexicana (L.) seed oil

This research article deals with the determination of optimal conditions of extraction parameters (e.g. temperature (60–100?°C), pressure (200–350?bar), particle size (0.5–1.0?mm), flow rate-CO₂ (5–15?g/min), and the % of co-solvent (0.0–10% of flow rate-CO₂) resulting to the optimal cumulative extraction yield during the supercritical fluid extraction of Argemone mexicana (L.) seed oil with and without a modifier (ethanol) using a supercritical carbon dioxide as solvent. A “five-factors-three-levels” Box-Behnken design under the response surface methodology was used to show independent and interactive effects of extraction parameters. A mathematical regression model was expressed properly by a quadratic second-order polynomial equation. The maximum oil yield (42.86%) from A. mexicana seeds was obtained with the optimal conditions (85?°C, 305?bar, 0.75?mm, 11?g/min, and 9% of flow rate-CO₂) of extraction parameters. The fatty acids analysis of the seed oil was done using gas chromatography and found its suitability as bio-fuel.     

Fractionated extraction of saponins from Brazilian ginseng by sequential process using supercritical CO2, ethanol and water

Saponins are surfactants that reduce the surface tension of aqueous solutions, besides having pharmacological actions. In order to extract and fractionate saponins from Pfaffia glomerata roots and Hebanthe eriantha roots using supercritical technology, fractionated extracts were obtained from a sequential process in fixed bed using supercritical CO₂ (scCO₂), ethanol, and water as solvents. All extractions were carried out in four sequential steps, at 50 °C and 300 bar. In the first step, pure scCO₂ was used as solvent, while (a) scCO₂/etanol (70:30, w/w); (b) ethanol, and (c) ethanol/water (70:30, v/v) were used as solvents in the three subsequent steps. The extracts were analyzed by thin layer chromatography (TLC) and surface tension. The extraction yields of the four steps were 0.16, 0.55, 1.00, and 6.90% for P. glomerata roots, and 0.17, 0.58, 0.89, and 28% for H. eriantha roots, showing a predominance of high polarity compounds in these species. TLC analysis showed that the extraction process was selective according to the polarity of the solvent, and provided extracts containing different saponins, except for scCO₂ extraction. The extracts from the extraction using ethanol + scCO₂ (Step 2) showed the greatest ability to reduce the surface tension of water from 72 mN m⁻¹ (pure water) to 25 mN m⁻¹, suggesting that this step was the best for extraction of less polar saponins in the extracts. The critical micelle concentration (CMC) values were approximately 2 and 8 g L⁻¹ for P. glomerata and H. Eriantha, respectively. These results confirmed the efficacy of the extraction process under study.     

Extraction of jojoba oil by pressing and leaching

Jojoba oil extraction by pressing alone, pressing followed by leaching, and leaching alone were investigated. The extraction process by first and second pressing followed by leaching gave about 50% by weight oil with reference to total seed, which is in agreement with what has been reported previously. The extraction by leaching process was carried out using different solvents. These solvents were; hexane, benzene, toluene, petroleum ether, chloroform, and isopropanol. Hexane, benzene, and petroleum ether gave the highest yield (all about 50% by weight oil with reference to total seed), but when cost is considered, petroleum ether is recommended as the best solvent to leach jojoba oil. The yield obtained in this work for leaching by hexane and benzene are 3–5% and about 10% for isopropanol more than those reported in the literature. Traces of solvent remained with the extracted oil after simple distillation followed by a second stage distillation via a Rotavapour apparatus. These traces slightly affected some of the oil properties such as pour point and flash point.     

On-line extraction-reaction of canola oil using immobilized lipase in supercritical CO2

Lipase-catalyzed hydrolysis of canola oil in supercritical CO₂ (SCCO₂) was studied as a model reaction to develop an on-line extraction–reaction process to extract oil from oilseeds and convert the oil to other valuable products using SCCO₂. Immobilized lipase from Mucor miehei was used as the catalyst and the process was carried out at 24 MPa and 35°C. Product composition was analyzed using supercritical fluid chromatography. The effect of enzyme load, CO₂ flow rate and canola flake load on the amount of product and its composition was investigated. Hydrolysis occurred to a larger extent to free fatty acids and glycerol with an increase in enzyme load, a decrease in CO₂ flow rate or a decrease in canola load. On-line extraction-reaction process using SCCO₂ shows great potential for new process design to obtain products from agricultural commodities for use as ingredients in food and other industries.     

Extraction and solubility evaluation of functional seed oil in supercritical carbon dioxide

Hemp (Cannabis sativa L.) seed oil is valued for its nutritional properties and for the health benefits associated with it. Its greatest feature is that the ratio of linoleic acid and linolenic acid is the desirable value of 3:1. In this research, supercritical carbon dioxide was applied to extraction of functional oil from hemp seed. In order to determine the effect of temperature and pressure on the yield of extracted components, the oil was extracted from hemp seed at temperatures between 40 and 80 °C, pressures of 20–40 MPa and a CO₂ flow rate of 3 mL/min. The solubility of hemp seed oil in SCCO₂ determined experimentally was fitted to the Chrastil equation to determine the model parameters. The solubility calculated by Chrastil equation was compared with the experimental data. Finally, the fatty acid profile of the oil was evaluated by gas chromatography-flame ionization detection (GC-FID). There are no significant differences in the compositions of five abundant fatty acid components of the oil obtained at different sampling times with SCCO₂ extraction and other extraction methods.     

Fractionation of menhaden oil ethyl esters using supercritical fluid CO2

Supercritical fluid CO₂ was used to fractionate menhaden oil fatty acid ethyl esters to obtain concentrates of the esters of allcis-5,8,11,14,17-eicosapentaenoic acid (EPA) and allcis-4,7,10,13,16,19-docosahexaenoic acid (DHA). Separation of the ethyl esters was found to occur primarily by carbon number, thus limiting the degree to which the ethyl esters of EPA and DHA could be concentrated. Urea fractionation of whole esters in order to remove saturates, monoenes and dienes prior to fractionation with supercritical fluid CO₂ resulted in concentrates of EPA and DHA in purities exceeding 90%. Several criteria are given for the selection of crude oils in order to maximize both purity and yield of concentrates.     

枸杞籽油超临界二氧化碳萃取方法的实验研究

建立了一套超临界流体萃取枸杞籽油实验流程．以CO2为萃取剂,考察了萃取压力、操作温度、CO2流量及原料颗粒度等因素对枸杞籽油萃取率的影响,确定了较佳的萃取工艺条件：压力30MPa,温度313-318K,枸杞籽颗粒40-50目,CO2流量0．3—0．4m^3/h时枸杞籽油萃取率最高,可达155％.     

Quality of residual oil from palm-pressed mesocarp fiber (Elaeis guineensis) using supercritical CO2 with and without ethanol

The qualities of oils extracted from fresh and dried palm-pressed mesocarp fiber were evaluated. The means of extraction included conventional solvent extraction and supercritical carbon dioxide (SC-CO₂) extraction with and without addition of ethanol. Extraction efficiency using pure SC-CO₂ and the effect of moisture content on efficiency were studied. Minor components, such as vitamin F, carotenoids, squalene and phytosterols, obtained by different methods were compared. The quality of oil recovered from fresh palm-pressed fiber is generally better than that of oil recovered from dried fiber. The SC-CO₂ extraction rate was lower for fresh fiber than for dried fiber. The incorporation of ethanol with SC-CO₂ resulted in oil with higher oxidative stability than did SC-CO₂ alone. Concentrations of minor components and the acylglycerol compositions of the oils extracted from both types of fibers were similar.     

酒精蒸馏中杂醇油的分离过程模拟与优化

以酒精五塔蒸馏工艺为依据,利用流程模拟软件Aspen Plus建立对酒精蒸馏中杂醇油分离回收过程的模型,模拟结果与实际工业过程数据相符。针对工艺中关于杂醇油的操作参数做出分析和优化,模拟结果可为生产实践中调节各操作参数对杂醇油分离回收效率的影响提供参考和借鉴。     

A wet process technology applied to jojoba seed to obtain oil and detoxified protein meal

An industrial wet process to obtain oil and meal from jo-joba was set up. The process sequence consists of breaking the seeds, homogenizing with water of suitable pH and temperature, and centrifuging to accomplish separation into oil, process water and wet meal. Oil is obtained with a yield of 70–75% and requires no supplementary refining treatment for the industrial purposes for which it is destined. The meal obtained is devoid of the toxic components simmondsin and simmondsin-2′ ferulate, and the protein content may be considered unchanged. The procedure contemplates a drying treatment for the meal with a view to using it as animal feed. This system is simple, economical and flexible in use.     

CO2 partial density distribution during high-pressure mixing with ethanol in the supercritical antisolvent process

A two-dimensional Raman scattering technique was used to locally and temporally resolve the effect of the mixture formation process on the carbon dioxide (CO₂) partial density distribution in the pulsed supercritical antisolvent (SAS) process. The solvent ethanol was injected into the antisolvent CO₂ in the vicinity of the binary mixture critical pressure (MCP). The acquired Raman images were converted into CO₂ partial density distributions. For pressures far above the MCP, CO₂ partial densities were not affected by the presence of the injected ethanol in the operational sphere of the jet. For pressures slightly below the MCP, CO₂ partial densities were measured three times higher in the operational sphere of the ethanol spray than in the surrounding bulk region. To reach equivalent CO₂ partial densities far above the MCP, chamber pressures as high as 100 MPa would be necessary.     

A shrinking core model and empirical kinetic approaches in supercritical CO2 extraction of safflower seed oil

Utilization of supercritical CO₂ in safflower seed extraction was performed using a semi-batch extractor. Different extraction parameters, such as 40–60 MPa pressure, 323–347 K temperature, 20–76 min time, and 1–3 mL/min CO₂ flow rate were applied. A two-stage experimental design application was performed in order to maximize the oil yield. First of all, a 3² factorial design was applied to estimate the effect of the main factors and their interactions. The second part of the experimental design was improved and accelerated using the steepest ascent method. Optimum extraction parameters were determined to be 50 MPa pressure, 347 K temperature and 76 min time at a constant CO₂ flow rate (3 mL/min) according to the 2² design. Under these conditions, the oil yield obtained was 39.42%, comparable with Soxhlet extraction (40%) for 8 h. Shrinking core and empirical kinetic models were applied in order to generalize the extraction process. The predicted data was compatible with the experimental data.     

响应曲面法优化超临界CO2萃取猕猴桃籽油条件

以猕猴桃籽为试验原料,在单因素试验的基础上,采用响应曲面分析法建立了超临界CO2萃取猕猴桃籽油萃取率的二次多元回归方程,探讨了压力、温度、CO2流量等关键因素对萃取率的作用规律。结果表明,萃取压力、温度、CO2流量对萃取率影响显著,萃取压力和温度交互效应影响显著。根据萃取率回归方程对猕猴桃籽油的超临界萃取工艺参数进行了优选,最优工艺参数为:压力31.7 MPa,温度40.2℃,CO2流量27.4 kg/h,该条件下萃取率高达32.57%,与试验值31.24%仅有4.5%的误差,证实了该方程的预测值与试验值之间具有较好的拟合度。超临界CO2萃取的猕猴桃籽油与己烷提取的油脂在脂肪酸组成上没有显著差别。