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《云南化工》2016,(4):12-16
为了解决传统溶剂萃取贡菊净油过程中溶剂残留和香味物质损失的问题,通过二甲醚亚临界萃取贡菊的单因素实验及正交实验,研究了萃取压力、萃取温度、萃取时间及液固比对萃取提取率的影响,确定了二甲醚亚临界萃取提取贡菊净油的最佳工艺条件。结果表明,各影响因素对贡菊净油提取率作用的大小依次为:萃取压力液固比萃取温度萃取时间。最佳工艺参数为:萃取压力0.5MPa、萃取温度20℃、萃取时间3 h、液固比7∶1 m L/g,贡菊净油提取率平均值为4.19%。该净油可提升烟草香气丰富性,能赋予卷烟产品独特的风格特征,明显提升卷烟的抽吸品质。优化得到的工艺可提高贡菊净油的得率,工艺可行稳定。 相似文献
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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
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以紫草为研究对象,采用单因素实验考察了提取温度、料液比、乙醇体积分数对紫草总萘醌提取量的影响;在单因素实验的基础上,采用正交实验优化了紫草总萘醌的加热回流提取工艺。结果表明:在提取时间为2 h、提取温度为90℃、料液比为1∶50(g∶mL)、乙醇体积分数为90%的最优条件下,紫草总萘醌提取量可以达到30.03 mg·g-1。该研究为紫草药用植物资源的开发利用提供了参考。 相似文献
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微波萃取法提取水豆腐中大豆异黄酮工艺研究 总被引:1,自引:0,他引:1
文章以乙醇为溶剂,采用微波萃取法,对水豆腐中大豆异黄酮的提取工艺进行探究.通过单因素实验考察了乙醇浓度、提取温度、微波萃取时间、固液比对微波提取率的影响.结果表明:从水豆腐中提取大豆异黄酮的最佳提取工艺为:乙醇浓度70%,提取温度50℃,微波萃取时间30 min,固液比1∶12. 相似文献
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文章以乙醇为溶剂,采用微波萃取法,对水豆腐中大豆异黄酮的提取工艺进行探究。通过单因素实验考察了乙醇浓度、提取温度、微波萃取时间、固液比对微波提取率的影响。结果表明:从水豆腐中提取大豆异黄酮的最佳提取工艺为:乙醇浓度70%,提取温度50℃,微波萃取时间30 min,固液比1∶12。 相似文献
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蛇床子油为绿黄色或绿棕色挥发性油,具有蛇床子特有气味。为发掘及提升蛇床子油的品质,本研究采用亚临界法探讨水萃取蛇床子油的工艺条件及保润性能。采用单因素试验及中心试验研究萃取压力、温度、时间、液固比对蛇床子油得率的影响,从而确定了最佳萃取工艺条件。研究结果显示,最优工艺条件为亚临界萃取压力8.50 MPa、萃取温度144.84℃、液固比(mL/g)为35.89∶1、萃取时间7.96 min,最高得率为40.974 mg/g。结果表明通过亚临界水萃取得到的蛇床子油可用于卷烟保润。 相似文献
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以艾叶挥发油提取率为考核指标,采用单因素实验考察浸泡时间、料液比、提取时间等对艾叶挥发油提取率的影响,在此基础上,采用响应面法优化艾叶挥发油的共水蒸馏提取工艺,并通过紫外分光光度法测定艾叶挥发油对DPPH自由基的清除率来评价其抗氧化性能。结果表明,艾叶挥发油的最佳提取工艺条件为:浸泡时间1.5 h、料液比1∶10(g∶mL)、提取时间4.5 h,在此条件下,艾叶挥发油提取率最高,为0.83%。当艾叶挥发油浓度为80 mg·mL~(-1)时,DPPH自由基清除率最高,为39.12%。表明艾叶挥发油具有一定的抗氧化活性。 相似文献
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文中建立了固相微萃取-气相色谱串联两级质谱法测定地表水中的10种藻类代谢产物的含量,研究了萃取时间、萃取温度、萃取剂量、萃取纤维等预处理参数对嗅味物质含量的影响,同时对不同规格的色谱柱进行分离效果比较。结果表明,在萃取时间为25 min、萃取温度为65℃、氯化钠含量为1.7 g的测定条件下,采用50/30μm DVB/CAR/PDMS萃取头进行预处理,HP-5MS色谱柱进行分离,质谱检测器进行测定,可以使检测结果达到最优效果。方法的质量浓度均达到5.00~100.00 ng/L,工作曲线回归方程的相关系数R2>0.995;方法检出限(2S/N)为0.14~1.00 ng/L。在纯水加标量为20.00、50.00、80.00 ng/L时,平均回收率为92.0%~109.0%,精密度RSD为0.4%~8.9%,实际水样加标的平均回收率为83.9%~101.8%。该方法检测浓度数量级在纳克级,灵敏度较固相萃取-气相色谱-质谱法提高1 000倍,更适合地表水和饮用水中低浓度藻类代谢产物的检测要求。 相似文献
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Jun Xue Wei Wang Qunhui Wang Shu Liu Jie Yang Tingji Wui 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2010,85(9):1268-1277
BACKGROUND: Municipal solid waste incinerator (MSWI) fly ash is regarded as hazardous waste because it contains various toxic metals. A previous study has shown that fly ash can be detoxified by removal of heavy metals. In this work, the extractability of heavy metals from MSWI fly ash by traditional and microwave acid extraction were compared. RESULTS: A 24 ? 1 fractional factorial experimental design was adopted using acid concentration, extraction time, temperature, and liquid/solid (L/S) ratio as the experimental factors for traditional extraction, and acid concentration, extraction time, liquid/solid (L/S) ratio and microwave power as the experimental factors for microwave extraction. The traditional extraction results show that L/S played an important role in Zn, Cd extraction while L/S ratio and extractant concentration were important for Pb extraction. However, no controlling parameter was determined for Cu and Cr extraction. For the microwave extraction, it was shown that L/S was important for Pb and Zn and extractant concentration was important for Pb, Zn and Cd. The time and the power were not significant for the extractability of heavy metals. CONCLUSION: Hydrochloric acid was an effective extractant. Microwave heating promoted extraction and shortened extraction time. Microwave acid extraction treatment is a potentially feasible method for the removal of heavy metals from MSWI fly ash. Copyright © 2010 Society of Chemical Industry 相似文献
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Extraction and Fermentation‐Based Purification of Saponins from Sapindus mukorossi Gaertn. 下载免费PDF全文
Wu Heng Zhang Ling Wang Na Guo Youzhi Weng Zhen Sun Zhiyong Xu Deping Xie Yunfei Yao Weirong 《Journal of surfactants and detergents》2015,18(3):429-438
In the present study, the extraction and purification of saponins from Sapindus mukorossi Gaertn. were examined for effective utilization of the saponin resource. Saponins were extracted from S. mukorossi Gaertn. using water. The conditions of the water extraction process, including extraction temperature, extraction time, number of times of extraction, and solvent‐material ratio were optimized. The yield of total Sapindus saponins (TSS) from the pericarp was 33.41 % and its purity in the extract was 45.71 %. The saponin solution was further concentrated to 1/6–1/7 of its original volume, and dried yeast BV818 that adapted to the concentrated Sapindus saponins solution (SW) was screened. The activation conditions, inoculum amount, fermentation temperature, and fermentation period were optimized. By using the dried yeast under optimized conditions, the purity was increased to 75.50 %. The yield of the byproduct ethanol was 5.33 % (w/v), while the content of TSS in the final product decreased from 18.29 to 15.30 % (w/v). These results could contribute to the development of industrial‐scale production of Sapindus saponins. 相似文献
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The U.S. Bureau of Mines investigated solvent extraction methods for recovering germanium from sulfuric acid leach filtrates. A new organic extractant system was developed which synergistically and selectively recovered germanium from these solutions. A continuous solvent extraction circuit was operated for over 150 hr, extracting over 90% of the germanium from 0.30 g/L Ge filtrates containing 40 to 60 g/L free acid. Over 90% of the loaded germanium was stripped from the organic phase with water at 75 °C. A section on germanium and gallium co-extraction is also presented. 相似文献
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The sequential extraction process (SEP) uses ethanol to extract oil and protein from cracked, flaked, and dried corn, and
the dried corn simultaneously dehydrates the ethanol. Value-added co-products are possible, potentially making production
of fuel ethanol more economical. The effects of solvent-to-corn (S/C) ratio, corn moisture content (MC), and number of extraction
stages on ethanol drying, oil recovery, and protein loss during the simultaneous oil extraction/water adsorption step of SEP
were evaluated. Extractions were carried out by using both aqueous ethanol and ethanol/hexane blends at 56°C. The S/C ratios
tested were 3∶1, 2∶1 (control), 1.5∶1, and 1∶1 (w/w). More anhydrous ethanol, greater oil yields, and less co-extracted protein
were obtained with higher S/C ratios. Less anhydrous ethanol and lower moisture adsorption capacities were obtained when the
corn MC was ≥1.12%. Oil yields gradually decreased with drier corn, whereas protein loss increased when corn MC was <1.12%.
Reducing the number of extraction stages from seven (original SEP) to five did not affect ethanol drying capability, oil yields,
and protein co-extracted with oil. Using ethanol/hexane blends resulted in more anhydrous ethanol, higher oil yields, and
less protein co-extracted with oil. 相似文献
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对仙人掌粉水提工艺进行了优化。分别进行酶的添加、酶的筛选、酶解时间的确定和离子交换工艺的优化,确定了最终的提取工艺流程。并对仙人掌冻干粉酶提液和水提液的化妆品功效(抗敏舒敏性、保湿性)进行了评价和对纤维素酶提仙人掌粉提取液进行了稳定性测试。结果确定采用纤维素酶,提取的工艺条件为温度50℃,pH为5,g/s为1%,固液比为1:20,酶解时间为1h,离子交换上样比例为1:6。酶提法提取的仙人掌粉提取液在抗敏舒敏性、保湿性上均优于水提法提取的仙人掌粉提取液。纤维素酶提仙人掌粉提取液的稳定性良好。 相似文献
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Sang Cheol Lee Won Kook Lee 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1992,55(3):251-261
The extraction of penicillin G from simulated media was performed by water/oil/water (w/o/w) emulsion liquid membranes (ELMs) and studied under various operational conditions in a batch system. The degree of extraction achieved was between 80% and 95% under specific conditions. A concentration of greater than nine times the initial concentration of penicillin G in the external phase was obtained in the internal phase. The pH of the internal aqueous solution, containing a basic salt, was theoretically calculated on the basis of the amount of penicillin G transported into the internal phase. The calculated results agreed with the experimental data well and were used to select a suitable type and concentration of a basic salt in the internal phase to give a pH within the range 5 to 8 where penicillin G was stable after the termination of extraction. The extraction of penicillin G was successfully performed by the ELM process with sodium carbonate in the internal phase. 相似文献