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微波协同萃取射干异黄酮的研究 总被引:1,自引:0,他引:1
Microwave-assisted extraction (MAE) of isoflavones from Belamcanda chinensis was studied using ethanol as the solvent. The single factor experiment and the orthogonal method were used to optimize the MAE condition. It was concluded that two doses of intermittent microwave power radiation, 300 W each for 4 rain, were needed for extraction. The mass ratio of solvent to material was 8:1 and the alcohol mass fraction was 80%. The extracted liquor was then concentrated under vacuum and degreased with petroleum ether. The yield of total isofiavones was about 8.8% and the contents of tectoridin and iridin were 67.6% and 16.3% respectively. Compared with direct-heating extraction (DHE), MAE may shorten extracting duration, reduce solvent consumption, and improve yield and purity of isoflavones from Belamcanda chinensis. 相似文献
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新型己内酰胺萃取剂的筛选和评价 总被引:2,自引:1,他引:1
Mixed solvent of 1-octanol and cyclohexane with 60% (by mass) 1-octanol content was selected as a new extractant for caprolactam extraction. Compared with benzene or toluene, the new extractant has larger extraction capacity and much lower toxicity. Although the extraction capacity of the new extractant is smaller than that of pure 1-octanol, 1-octanol solubility of the new extractant in aqueous phase is much smaller. Because of its physical properties of lower density, lower viscosity, and higher interfacial tension, the new extractant performed much better phase separation ability than pure 1-octanol. The new extractant showed certain selectivity when dealing with lactam oil. The mixed solvent of 1-octanol and cyclohexane with 60% (by mass) 1-octanol content is a promising extractant for caprolactam extraction. 相似文献
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In this study, extraction of p-cresol from the simulated wastewater has been studied using centrifugal extractors and QH-1 extractant. The distribution ratio of p-cresol was approximately 308.5 in the QH-1-p-cresol (pH =2.0) system. The extraction stage efficiency of the single-stage centrifugal extractor was higher than 92%, and the extraction rate of the three-stage cascade was higher than 99%. When 15% NaOH was used for the stripping of p-cresol in QH-1 solution, the stripping rate of the three-stage cascade reached 100%. A mathematical model of multistage countercurrent extraction process that considers the phase volume change, extraction stage efficiency, and phase entrainment was used to simulate the extraction of p-cresol using centrifugal extractors. The calculated results using this model were in good agreement with the experimental results. 相似文献
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To explore the feasibility of extracting aromatic acid products from oxidizing coal, two aromatic acids, trimellitic and [1,1′-biphenyl]-2,2′-dicarboxylic acid, were selected as the solutes, and the extraction equilibrium of the acids were studied with 1-octanol, 50% tributyl phosphate (TBP) in kerosene, and 10% trialkylphosphine oxide (TRPO) in kerosene. The results showed that the degree of extraction of [1,1′-biphenyl]-2,2′-dicarboxylic acid was larger than that of trimellitic acid for all of the solvent, and the extraction capacity with TRPO is more effective than the one with TBP. The extraction behavior of aromatic polyacid is different from that of carboxylic acid, and the reactive extraction function of aromatic acids with TBP and TRPO is not as effective as that of carboxylic acid. 1-octanol could be used to remove [1,1′-biphenyl]-2,2′-dicarboxylic acid from the mixture of trimellitic acid and [1,1′-biphenyl]-2,2′-dicarboxylic acid. Because the weak hydrogen bond association exists between -OH in 1-octanol and -COOH in aromatic acid, the extractive selectivity of [ 1, 1′-biphenyl]-2,2′-dicarboxylic to trimellitic acid depends on the stoichiometric ratio. 相似文献
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Shanjin Zeng Chuandong Tao Richard Parnas Wei Jiang Bin Liang Yingying Liu Houfang Lu 《中国化学工程学报》2016,24(11):1640-1646
Biodiesel, which is a renewable and environmentally friendly fuel, has been studied widely to help remedy increasing environmental problems. One of the key processes of biodiesel production is oil extraction from oilseed materials. Switchable solvents can reversibly change from molecular to ionic solvents under atmospheric CO_2,and can be used for oil extraction. N, N-dimethylcyclohexylamine(DMCHA), a switchable solvent, was used to extract oil from Jatropha curcas L. oil seeds to produce biodiesel. The appropriate extraction conditions were:1:2 ratio of seed mass to DMCHA volume, 0.3–1 mm particle size, 200 r·min-1agitation speed, 60 min extraction time, and 30 °C extraction temperature. The extraction ratio was about 83%. This solvent extracted the oil more efficiently than hexane, and is much less volatile. By bubbling CO_2 under 1 atm and 25 °C for 5 h, the oil was separated, and DMCHA was recovered after releasing CO_2 by bubbling N_2 under 1 atm and 60 °C for 2 h. The residual solvent content in oil was about 1.7%. Selectivity of DMCHA was evaluated by detecting the protein and sugar content in oil. Using the oil with residual solvent to conduct transesterification process, the oil conversion ratio was approximately 99.5%. 相似文献
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Pre-dispersed solvent extraction (PDSE) was used to extract quercentin from its diluted solution. The influences of temperature, phase volume ratio (PVR), concentration of sodium Dodecyl benzene sulphonate and pH value etc. on the extraction efficiency were examined. It is found that, compared with traditional extraction techniques under the same condition, a higher extraction productivity can be obtained by PDSE. The stability of colloidal liquid aphrons plays an important role in this process. In a certain scope, the extraction efficiency increases with PVR. Excessive amount of solvent is not much helpful. A new analytical method by using ultraviolet spectrometer to determine the concentration of quercentin is established. 相似文献
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Pre-dispersed solvent extraction (PDSE) was used to extract quercentin from its diluted solution. The influences of temperature, phase volume ratio (PVR), concentration of sodium Dodecyl benzene sulphonate and pH value etc. on the extraction efficiency were examined. It is found that, compared with traditional extraction techniques under the same condition, a higher extraction productivity can be obtained by PDSE. The stability of colloidal liquid aphrons plays an important role in this process. In a certain scope, the extraction efficiency increases with PVR. Excessive amount of solvent is not much helpful. A new analytical method by using ultraviolet spectrometer to determine the concentration of quercentin is established. 相似文献
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The extraction of ethanol with the solvents of aldehydes mixed with m-xylene was studied for the bioethanol concentration process.Furfural and benzaldehyde were selected as extraction solvents,with which the solubility of water is small,expecting large distribution coefficient of ethanol.The liquid–liquid two-phase region was the largest with m-xylene solvent,followed by benzaldehyde and furfural.The region of two liquid–liquid phase became larger with the mixed solvent of m-xylene and furfural than that with furfural solvent.The NRTL model was applied to the ethanol–water–furfural–m-xylene system,and the model could well express the liquid–liquid equilibrium of the system.For any solvent used in this study,the separation selectivity of ethanol relative to water decreased as the distribution coefficient of ethanol increased.The separation selectivity with m-xylene was the largest among the employed solvents,but the distribution coefficient was the smallest.The solvent mixture of furfural and m-xylene showed relatively high distribution coefficient of ethanol and separation selectivity,even in the higher mass fraction of m-xylene in the solvent phase.The ethanol extraction with a countercurrent multistage extractor by a continuous operation was simulated to evaluate the extraction performance.The ethanol content could be concentrated in the extract phase with relatively small number of extraction stages but low yield of ethanol was obtained. 相似文献
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We studied the separation and recovery of copper(Ⅱ), nickel(Ⅱ), cobalt(Ⅱ), zinc(Ⅱ), and cadmium(Ⅱ) from magnesium and calcium, using synergistic solvent extraction(SSX) in a typical hydrometallurgical waste solution. A mixture of Versatic 10 acid and Mextral 984 H, diluted with Mextral DT100, was used to obtain fundamental data on p H and distribution isotherms, as well as the kinetics of extraction and stripping. We also investigated the main effects and interactions of common solvent extraction factors: the extraction p H at equilibrium, the temperature, and the extractant concentration. The synergistic effect for extracting metals was confirmed. The results showed that the addition of Mextral 984 H enhanced the separation factors of copper, nickel, cobalt,zinc, and cadmium over magnesium and calcium. Compared with Versatic 10 acid alone, for a mixture of0.5 mol·L~(-1) Versatic 10 acid/0.5 mol·L~(-1)Mextral 984 H, Δp H50 values of copper, nickel, cobalt, zinc, and cadmium were found to be N 2.0, 3.30, 2.85, 0.95, and 1.32 p H units, respectively. The Δp H_(50)(Zn–Mg)and Δp H_(50)(Zn–Ca)values were 3.27 and 2.25, respectively, indicating easy separation and recovery of copper, nickel, zinc, cobalt,and cadmium. The extraction and stripping of copper, cobalt, zinc, and cadmium were fast, with 90% of the metal transferred in 2 min. We next studied whether the metals could be stripped from the extracted liquid selectively in sequence, by using sulfuric acid at different concentrations. The influence of the molecular structure of the oxime and carboxylic acid components upon the synergistic effects was identified by numerical analysis.Excellent separation of copper, nickel, cobalt, and zinc over magnesium and calcium was achieved with this synergistic solvent extraction system. 相似文献
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《过程工程学报》2016,(6)
A novel and efficient extraction/hydrolysis method was developed for the recovery of resveratrol and emodin from a well-known traditional chinese medicinal herb, Polygonum cuspidatum. By using a 85% aqueous acetone solution containing 1.0 mol/L HCl as extractant, extraction of resveratrol and emodin from P. cuspidatum and conversion of resveratrol-3-O-β-glucoside and emodin-8-O-β-D-glucoside into the products could be achieved in one step. The effects of several key parameters including concentration of HCl and acetone, temperature, ratio of solvent to material, extraction duration and extraction times on the process efficiency was systematically investigated. The results showed that the optimal conditions for maximizing the recovery yield were 85% acetone containing 1.0 mol/L HCl as extractant, temperature 70 ℃, ratio of liquid to solid 50 mL /g and extraction duration 30 min. This one-pot extraction/hydrolysis process increased the yield of resveratrol and emodin to 524% and 302%, respectively, compared to a raw sample without hydrolysis. Compared with conventional method, the developed process not only achieved high yield of resveratrol and emodin, but simplified the procedures and reduced time. The results demonstrated that the simultaneous extraction/hydrolysis process is simple and efficient which could act as a useful approach for enhanced recovery of resveratrol and emodin from P. cuspidatum. 相似文献
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method of extracting astaxanthin from Phaffia rhodozyma with various solvents after acid washing was investigated. The extraction efficiency was distinctly increased after acid washing of P. rhodozyma cells. When the concentration of HCl was 0.4 mol·L-1, the highest extraction efficiency of astaxanthin was achieved which was about three times higher than the control. Acetone or benzene as single polar or non-polar solvent was the most effective solvent in our research. With a combination of isopropanol and n-hexane (volume ratio of 2:1), the maximal extraction efficiency was achieved, approximately 60% higher than that obtained with a single solvent. The liquid-solid ratio and the extracting time were also optimized. Under the optimum extraction conditions, the extraction yield of astaxanthin exceeded 98%. 相似文献
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以雨生红球藻湿藻泥为原料,研究了不同有机溶剂对胞内油脂和虾青素选择性提取分离的影响,通过酸解破壁提高虾青素和油脂的提取效率。结果表明,连续乙醇提取可对胞内色素和油脂有效分级提取,先提取出极性组分(叶绿素和极性脂),再提取中性组分(类胡萝卜素和中性脂)。中等极性溶剂或溶剂体系对类胡萝卜素的选择性和提取率较好;乙醇/乙酸乙酯混合溶剂提取类胡萝卜素的总得率(干重)达25.31 mg/g,提取率为69.35%。对雨生红球藻湿细胞进行酸解破壁处理有助于提高虾青素和油脂的提取率。在最优酸解破壁条件(盐酸浓度1 mol/L,温度60℃,时间60 min)下,含水80%的雨生红球藻藻泥的油脂总得率(干重)达418 mg/g,总脂提取率达97%。 相似文献
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研究了t-BAMBP[4-叔丁基-2-(α-甲基苄基)苯酚]/磺化煤油萃取体系,从提铯后的母液中,萃取分离钾铷的过程。考察了萃取时间、萃取剂浓度、萃取相比等萃取条件、水洗条件和反萃取条件对铷钾分离的影响。确定了适宜的工艺条件为:t-BAMBP浓度为0.7 mol/L,相比O/A=3∶1,萃取时间为5 min;以0.1 mol/L氯化钠溶液为洗涤剂,洗涤相比O/A=4∶1;以0.5 mol/L 氯化氢溶液为反萃剂,反萃相比O/A=5∶1。经过5级逆流反萃,铷的反萃率达到95.6%以上,铷钾的分离系数较高,实现了铷钾分离。 相似文献
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考察离子液体溴化-1-乙基-3-甲基咪唑([emim]Br)作为提取溶剂对中草药中白桦脂酸衍生物的提取特性,并找到最佳提取条件。以中草药皂角刺为原料,以离子液体溴化-1-乙基-3-甲基咪唑为提取溶剂,选取提取温度、提取时间和液固比3个因素,进行正交试验,考察提取得率,并与乙醇回流提取方式作对比,找到离子液体提取最佳条件。结果表明:乙醇回流提取对目标成分的提取得率为0.050%,离子液体溴化-1-乙基-3-甲基咪唑在不同条件下对目标成分的提取得率为0.079%—0.107%。在室温(25℃)、液固比30∶1、提取时间2 h的条件下离子液体对目标成分的提取得率为0.105%。离子液体溴化-1-乙基-3-甲基咪唑对中草药皂角刺中白桦脂酸衍生物的提取得率明显高于乙醇回流提取方式的提取得率,最佳提取条件为室温(25℃)、液固比30∶1,提取时间2h。 相似文献
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溶剂萃取法净化湿法磷酸的研究 总被引:8,自引:0,他引:8
研究了在用磷酸三丁酯作为主要萃取剂时萃取塔的结构参数和操作参数对萃取效率的影响,比较了洗涤条件对杂质离子的脱除效果,以及不同条件下反萃效果的差异。实验结果表明:萃取效率不会随着振动频率的增大而增大,当萃取酯中有夹带酸时振动频率越小萃取率就越大,萃取塔筛板间距为5.5cm时萃取效果最好;铵盐和钠盐的脱除硫酸根离子能力大致相同,加大它们的浓度或缩小洗涤相比有利于脱除硫酸根离子,反萃取操作容易。 相似文献
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选用新型高效萃取体系正辛醇+煤油混合溶剂,研究了正辛醇+煤油混合溶剂在萃取净化湿法磷酸过程中萃取温度和相比(萃取剂与磷酸的体积比)与磷酸萃取率和杂质分离系数之间的关系, 考察了硫酸和铁两种杂质对磷酸萃取率和分配比的影响。实验表明: 随着相比提高, 磷酸萃取率上升, 各杂质分离系数提高。提高萃取温度和增加铁含量会使磷酸萃取率和分配比呈减小趋势,硫酸的存在有利于磷酸萃取。通过对正辛醇+煤油体系萃取湿法磷酸系统性的基础工艺研究,以期为设计工业化应用路线提供理论和技术支持。 相似文献