Proposed Models for Subcritical Water Extraction of Essential Oils

Mechanisms that control the extraction rate of essential oil from Zataria multiflora Boiss. (Z. multiflora) with subcritical water (SW) were studied. The extraction curves at different solvent flow rates were used to deter-mine whether the extractions were limited primarily by the near equilibrium partitioning of the analyte between the matrix and solvent (i.e. partitioning thermodynamics) or by the rates of analyte desorption from the matrix (i.e. ki-netics). Four simple models have been applied to describe the extraction profiles obtained with SW: (1) a model based solely on the thermodynamic distribution coefficient KD, which assumes that analyte desorption from the ma-trix is rapid compared to elution; (2) one-site kinetic model, which assumes that the extraction rate is limited by the analyte desorption rate from the matrix, and is not limited by the thermodynamic (KD) partitioning that occurs dur-ing elution; (3) two-site kinetic model and (4) external mass transfer resistance model. For SW extraction, the thermodynamic elution of analytes from the matrix was the prevailing mechanism as evidenced by the fact that ex-traction rates increased proportionally with the SW flow rate. This was also confirmed by the fact that simple re-moval calculations based on determined KD (for major essential oil compounds) gave good fits to experimental data for flow rates from 1 to 4 ml·min-1. The results suggested that the overall extraction mechanism was influenced by solute partitioning equilibrium with external mass transfer through liquid film.

Techniques and Technological Aspects of Palm Oil (Elaeis guineensis) Processing in Cameroon

Crude palm Oil (CPO) processing is very popular in African Countries. In Cameroon, various actors are involved ranging from agro-industrial complexes to traditional processing by smallholders who use very inefficient equipment and thus have low oil extraction rates. Small-scale processing by smallholders dates back to the early 1980s and has witnessed a lot of changes as a result of new actors in the sector, changing technologies and to an extent, government policies. This paper attempts a review of the origins and evolution of small-scale palm oil processing using intermediate technology, highlighting its importance to both the farmer and the national economy. An attempt is made to look into the future of this activity, with proposals for its consolidation.

Extraction Process of Volatile Oil of Artemisiae Scopariae Herba

[Objectives]To obtain the optimal extraction process parameters of volatile oil of Artemisiae Scopariae Herba.[Methods]The controlled variable method was used to take the extraction amount of volatile oil as the evaluation indicator,and the effects of single factor solid-to-liquid ratio,soaking time and extraction time on the yield rate of volatile oil were investigated.[Results]When the solid-to-liquid ratio reached 1∶12,the soaking time reached 3 h,and the extraction time reached 2 h,the yield of volatile oil was the highest.[Conclusions]The conditions of this process are stable and feasible,and it is expected to provide a certain reference for extracting volatile oil from Artemisiae Scopariae Herba.

A Comparative Study of Flavonoid Water-Ethanol Extraction Process in Planted Trollius Chinensis

With rutin standard sample as the comparison, flavonoid extraction rate as an indicator, UV-2450 ultraviolet visible light spectrophotometer to measure flavonoid content in planted Trollius chinensis through orthogonal experiment, this experiment optimizes process condition of flavonoid in Trollius chinensis through water extraction and ethanol extraction. The result shows that flavonoid extraction rate of Trollius chinensis through ethanol extraction method is obviously higher than water extraction, and the optimal extraction process condition is： ethanol concentration is 75%, extraction time is 90min, extraction times are 3, and fluid material ratio is 20：1.

Optimization of Sesame Oil Extraction Process Conditions

In this study, the optimum operating conditions for sesame oil extraction were studied. N-hexane was used as a solvent. Different variables were investigated;sesame seeds particle sizes, ratio of solvent to seeds mass, contact time, stirring effect, roasting impact and extraction temperatures. Results obtained showed that higher rates of extraction were obtained when roasting sesame seed to 15℃. The ratio of solvent to seeds found to be 6:1 gave higher extraction. Moreover, stirring speed was tested and had been optimized to 600 rpm. Finally, the extraction under heating was studied and results showed that increasing operating temperature to more than 40℃ did not increase extraction efficiency.

Exergetic Efficiencies Evaluation of Flows and Operations on the Mechanical Extraction Process of <i>Jatropha curcas</i>Oil

Jatropha curcas oil is one of the most promising renewable energy sources for rural areas due to its ease of production, which can be used as an alternative to diesel and fuel oil. The development of sustainable energy has been the issue of the discussion about biofuel production given the considerable consumption amount of fossil fuel during the transformation process. And any production process that consumes a lot of energy records a significant destruction of useful energy, which leads to thermodynamic inefficiencies of the process. Besides, the focus on environmental safety is gradually shifting towards energy efficiency in industrial processing. Exergetic analysis is an effective tool for measuring the performance of a production process since exergy is a quantity that measures energy quality. This study assesses the scale of resource degradation in Jatropha oil mechanical extraction processes and finds improving possible pretreatments options for more efficient production. Data from experiments combined with existing databases have permitted to establish the exergy flow balance at each stage of production. The process exergetic yield varies from 29.85% to 35.41% according to the chosen pretreatment process. Mass exergy accounts for 67% of incoming flows and, for outgoing flows, more than 60% is associated with the mass exergy generated by the process waste. The uncertainties analysis on the results was used to validate model results, and to visualize the minimum values for the most unfavorable cases and the maximum values when all the parameters are at their optimum values.

Mutagenicity and Genotoxicity of Organic Extracts from Finished Water with Different Treatment Process

Purification of surface water is widely practiced with conventional water treatment processes like coagulation-flocculation, sedimentation, filtration,and disinfection. Some reports have specified that conventional wastewater purification processes do not effectively remove many chemical contaminants,

Optimization of Ethanol-Ultrasound-Assisted Destabilization of a Cream Recovered from Enzymatic Extraction of Soybean Oil

A novel method using ethanol and ultrasound to extract oil from cream obtained from enzyme-assisted aqueous extraction of soybean oil was developed.To evaluate the relationships between operating variables and free oil yield and to maximize the free oil yield,response surface methodology was introduced in this work.The developed regression model was fitted with R2=0.9591.Optimized variables were:ethanol concentration of73%,ethanol addition volume of 0.55 L/kg,ultrasound power of 427 W,ultrasound time of 47 s,and ultrasound temperature of 53℃.The free oil yield from the cream under the above conditions was 92.6±3.4%.Scanning electron microscopy(SEM)was used to evaluate the effect of ultrasonic treatment on ethanoltreated cream,and the SEM images clearly showed that the ultrasound treatment affected dispersing and fracturing of the microstructure of ethanol-treated cream.

Extraction Optimization and Composition Analysis of Volatile Oil from Fruit of Alpinia zerumbet

[Objectives] The aim was to determine the optimum process for the extraction of volatile oil from Alpinia zerumbet fruit.[Methods]Steam distillation was used to extract volatile oil from A. zerumbet fruit. Based on the single factor tests,an orthogonal test was designed to explore the effects of solid-liquid ratio,soaking time,extraction time and grinding degree of material on the extraction rate. The composition of volatile oil from A. zerumbet fruit was analyzed using gas chromatography-mass spectrometry( GC-MS),and the relative mass fraction of each component was determined by peak area normalization. [Results] With volatile oil yield as the index,the optimum extraction process was determined: solid to liquid ratio of 1∶ 10,soaking time of 0. 5 h,grinding degree of passing through 24-mesh sieve and extraction time of 5 h. A total of 29 compounds were isolated. Among them,the contents of α-terpinene( 24. 894%),1,8-terpadiene( 15. 527%) andα-pinene( 6. 982%) were relatively high. [Conclusions]The optimized extraction process for volatile oil from A. zerumbet fruit is stable and reasonable. Under the optimum extraction process,the extraction effect of volatile oil from A. zerumbet fruit was the best. The chemical components of volatile oil from A. zerumbet fruit were determined by GC-MS as α-terpinene( 24. 894%),1,8-terpadiene( 15. 527%) and α-pinene( 6. 982%).

月球资源开发利用的进展与展望

中国探月工程“绕、落、回”三步走圆满收官,后续将建立国际月球科研站,并进一步规划建立月球基地。月球探测任务由探测勘察进入到开发利用新阶段,月面资源的勘查、开发和利用是未来月球探测的重点任务。总结了月球资源开发利用方面的国内外重要进展,涉及月球资源勘探、水冰等挥发分分析、月球矿物冶炼与材料制备、月面建造与月壤3D打印等四个方面。同时,月球资源开发利用面临极端月面环境、独特月壤理化特性、全流程无人自主控制等重大挑战,为解决这些问题,提出了未来月球资源开发利用的重点任务和研究思路,可为后续科学研究和工程任务实施提供参考。

响应面法优化侧柏叶精油的超声辅助水蒸气蒸馏提取工艺

以侧柏叶精油提取率为评价指标,选取超声功率、超声时间、液料比和提取时间为考察因素,通过单因素实验及响应面法优化了侧柏叶精油的超声辅助水蒸气蒸馏提取工艺。结果表明,各因素对侧柏叶精油提取率影响的大小顺序为:提取时间>超声功率>超声时间>液料比;确定最佳提取工艺为:超声功率80 W、超声时间32 min、液料比14∶1 (mL∶g)、提取时间6 h,在此条件下,侧柏叶精油提取率为0.821%,与预测值(0.817%)接近。该方法操作简单、稳定可靠,为侧柏叶精油的进一步开发利用提供了理论依据。

响应面法优化皇帝柑精油提取工艺

利用响应面法优化水蒸气蒸馏提取皇帝柑精油的提取工艺条件.探究提取时间、液料比、NaCl添加量、超声波功率对皇帝柑精油得率的影响,确定最佳工艺条件.结果表明,一种皇帝柑精油的最佳提取工艺为提取时间1.6 h、液料比32 mL·g^(-1)、NaCl添加量1.8%,在此条件下皇帝柑精油得率为3.16%,与模型预测最大值3.19%相差无几,说明该提取工艺切实可行.

大蒜挥发油的提取工艺研究

主要对大蒜挥发油的提取工艺进行了研究。研究结果显示:当大蒜量、水量和蒸馏时间均为相同定值时,大蒜粉碎程度好,出油率会增加;当料液比、蒸馏时间和粉碎程度为定值时,大蒜浸泡后,挥发油出油率高;当料液比、蒸馏时间、浸泡时间和粉碎程度为定值时,大蒜去皮与带皮,大蒜挥发油出油率无明显差别,可以带皮提取,省时省力;浸泡时间达到25 h,蒸馏时间可大大缩短。这就为挥发油的大规模生产提供了依据。

连翘与陈皮混合挥发油提取与包合工艺优化

目的优选保和颗粒组方中连翘、陈皮混合挥发油提取工艺及β-环糊精(β-CD)包合工艺。方法以饮片粉碎粒度、提取时间、加水倍数为考察因素,挥发油收率为评价指标,采用L_(9)(3^(4))正交试验法优选。以β-CD与挥发油比例(g∶m L)、包合时间、包合温度为考察因素,挥发油包合率、包合物收率、包合物含油量的综合评分为评价指标,同上法优选包合工艺并验证。结果最佳提取工艺,将饮片粉碎至20目,加10倍水提取3 h。最佳包合工艺,β-CD∶挥发油为7∶1(g∶m L),45℃下包合反应3 h;紫外光谱扫描、X射线衍射、扫描电镜、薄层色谱等结果均证明形成了稳定的包合物。制成的包合物中连翘及陈皮混合挥发油的包合率为95.13%,包合物收率为87.84%,包合物含油量为10.29%,综合评分为76.70分。结论优化后的连翘及陈皮混合挥发油提取、包合工艺稳定可行。

蚕丝含油率微波萃取试验方法探讨

针对目前蚕丝含油率检测效率低、耗时长、资源浪费大的问题,选用微波萃取工艺,设计4因素3水平的正交试验,分析比较微波萃取法与索式萃取法在蚕丝含油率检测方面的应用,探讨微波萃取法的测试条件。试验结果表明:微波萃取法相比索式萃取法检测准确度更高,过程更环保,且检测时间和试剂用量更少;微波萃取温度、萃取时间、萃取功率及乙酸乙酯用量各因素对样品含油率测试结果的影响从大到小依次为萃取温度、乙酸乙酯用量、萃取时间和萃取功率。最优检测条件为:萃取温度67℃,乙酸乙酯用量40 mL,萃取时间15 min,萃取功率800 W。

前胡药材产地干燥加工方法研究

目的比较产地不同干燥加工方法对前胡药材质量的影响,筛选其最佳产地干燥加工方法。方法分别采用传统晒干、自然阴干和电热恒温鼓风干燥、真空干燥、红外干燥和真空冷冻干燥等干燥加工方法对前胡药材进行处理,以折干率、含水量、浸出物含量、颜色色度值以及4种香豆素类成分含量为指标,采用逼近理想解排序法进行综合质量评价。结果不同干燥加工方法下,12份前胡药材样品的折干率为31.56%~40.10%,含水量为6.96%~8.58%,浸出物含量为27.56%~43.10%,红绿度值为1.80~7.50,黄蓝度值为19.90~30.20,明度值为46.90~59.90;伞形花内酯、白花前胡甲素、白花前胡乙素、白花前胡E素的含量分别为≤0.05、3.70~14.05、0.72~2.37、0.81~3.90 mg/g,总含量为5.47~19.65 mg/g;40℃电热恒温鼓风干燥下的前胡药材综合得分最高。结论40℃电热恒温鼓风干燥是前胡药材最佳的产地干燥加工方法。

酸枣仁油的超临界CO_(2)萃取工艺及其抗氧化性研究

采用超临界CO_(2)萃取技术对酸枣仁进行油脂萃取。利用单因素实验方法考查了孔径、萃取温度、萃取压力、萃取时间四个因素对酸枣仁出油率的影响,最佳萃取条件下对酸枣仁油脂样品进行GC-MS组分分析及DPPH清除能力测定。结果表明:超临界CO_(2)萃取酸枣仁油的最佳工艺为过筛目数80目,温度为45℃,萃取压力40 MPa,时间30 min,在最佳萃取工艺条件下,出油率为29.40%。GC-MS检测结果表明酸枣仁油含有27种化合物,DPPH的清除率IC_(50)值为29.12 mg/mL。

负载活性炭接地极雾化电晕放电处理采油废水的研究

采油废水是油田污水中最难处理的污水之一,其由较多种难以被生物降解的有机物组成,成分较为复杂。本文采用接地极雾化电晕放电技术处理采油废水,即利用高压放电产生低温等离子体和活性氧物种·OH分解有机物,降解效果良好。并设置多组实验对比有无活性炭层对放电电流、处理效果的影响,以及不同活性炭层厚度、流量对净化效率的影响。

花椒籽资源利用研究进展

花椒籽是花椒的主要副产物之一,其营养成分主要包括花椒籽油和花椒籽蛋白等。花椒籽油的提取工艺包括传统工艺提取、超临界CO_(2)萃取、微波提取、分子蒸馏、超声波提取、有机溶剂提取、水酶法等;花椒籽蛋白的提取工艺包括盐法、碱溶酸析法、Osborne法、酶法等。花椒籽中药用化学成分主要有黄酮、多酚、多糖及生物碱等,主要具有抑菌、抗氧化、抗肿瘤、降低血清胆固醇等药理作用。目前对于花椒籽资源的利用主要集中在将花椒籽作为部分基础饲料,以达到促生长、提高饲料转化率和生长性能的作用。今后,应充分挖掘花椒籽作为新型饲料的潜在价值,实现花椒籽资源的高效利用。本文对花椒籽中营养分析、提取工艺、药理活性成分及药理作用进行综述,可为花椒籽资源利用提供参考。

基于正交设计优化新鲜川芎中挥发油提取工艺

为优化川芎挥发油提取工艺,建立以新鲜川芎为原料提取制备挥发油的新方法,采用正交试验设计对乙醇回流提取工艺条件进行优化,并进一步考察优选回收浓缩、油水分离等关键工艺参数。以藁本内酯和洋川芎内酯A作为指标成分,应用HPLC一测多评法进行含量测定。以提取量、油收率、油含量为评价指标,最终确定川芎挥发油提取制备新方法为:鲜川芎切片,加8倍量70%乙醇回流提取2次(以干药材计,第一次需测定鲜川芎水分,调节乙醇浓度为70%),每次1.5 h,滤液回收浓缩至2.0~3.0 g生药/mL,静置过夜,弃去水层,上层乳化层加热至60℃离心,分取油层,余下乳化层再加氯化钠至饱和并加热至60℃离心,合并油层,即得川芎挥发油。新方法所得川芎挥发油收率约为3%,藁本内酯和洋川芎内酯A含量达70%。该研究所建立的新方法生产设备要求低、操作简便易行,可实现川芎挥发油的高效制备,且含量高、品质优,为川芎挥发油的工业化生产提供了新思路和新方法。