Microwave-assisted solvent extraction of castor oil from castor seeds

This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction (MAE). MAE was performed using 5% ethanol in hexane as solvent at different extraction times, power intensities and solvent-to-feed (S/F, ml of solvent to gram of feed) ratios. The process parameters were optimized by statistical approach using historical data design of response surface method (RSM). The oils were characterized for yield, physicochemical properties, dielectric properties and oxidation stability, and comparison was also made with oil extracted using Soxhlet method. Results show that the maximum oil yield of 37% was obtained at 20 min with microwave power intensity of 330 W and S/F ratio of 20. The main fatty acid composition of castor oil is ricinoleic acid. The density, refractive index, dielectric properties and oxidation stability of oils are not affected by the extraction methods and extraction parameters of MAE. However, the MAE-extracted oil is more viscous compared to that by Soxhlet method. With extra caution on oil oxidation, MAE could be a promising solvent extraction method with an 86% less in processing time and a higher yield.     

Determination of oil content in oilseeds by analytical supercritical fluid extraction

The total oil content of soyflakes, canola seed and wetmilled corn germ were determined by analytical supercritical fluid extraction (SFE) with carbon dioxide as the extraction solvent. Results obtained by SFE were in excellent agreement with those obtained by a conventional Soxhlet technique with organic solvents. The analytical-scale SFE technique yielded average means within one standard deviation of the means derived from the organic solvent-based methodology. Matrices containing both high and low oil content were successfully extracted with carbon dioxide at comparable precision to that obtained with the standard procedure. The supercritical fluid-based technique appears to be a suitable replacement for traditional extraction methods with organic solvents, thereby potentially eliminating the costs associated with solvent disposal and exposure of laboratory personnel to toxic and flammable solvents. Presented at the 4th International Symposium on Supercritical Fluid Chromatography and Extraction, Cincinnati, Ohio, May 20–22, 1992.     

油砂沥青溶剂提取回收组合工艺

采用有机溶剂提取-超临界CO2回收溶剂这一组合方法对加拿大Athabasca油砂进行了提取分离及溶剂回收实验,通过实验筛选出最佳抽提溶剂为重整汽油。溶剂提取的最佳工艺条件:提取温度80℃,溶剂流量60mL/min,提取时间60min。在此条件下油砂沥青提取率达到92.74%。对超临界CO2-重整汽油体系的相行为进行研究,并通过实验综合考察了温度、压力、CO2流量以及回收时间等工艺操作条件对溶剂回收的影响。结果表明:在回收温度50℃,回收压力13MPa,溶剂与CO2分离温度70℃,压力5MPa,CO2流量7.5L/h,时间1h的条件下,重整汽油的回收率为98.71%。     

离子液体促进溶剂萃取油砂沥青

传统水洗法和溶剂萃取法萃取油砂沥青时,存在沥青中含有沙土和残沙中含有油等缺点。为解决上述缺点,本文采用不同比例的乙酸甲酯/正庚烷复合溶剂萃取油砂沥青,研究了离子液体（1-丁基-3-甲基咪唑四氟硼酸盐,[Emim]BF4）对该溶剂萃取体系的萃取率和分离洁净程度的影响。采用红外光谱仪和扫描电镜对萃取后的残沙和沥青的洁净程度进行了定性分析,并结合元素分析仪和电感耦合等离子体发射光谱仪获得萃取后残沙和沥青的洁净程度的定量结果。实验结果表明：当复合溶剂体积比为2∶3时,[Emim]BF4促使沥青回收率达到最大值94.20%,比单纯复合溶剂萃取体系的最大萃取率高7.92%;通过上述测试方法的定性和定量分析,证明了[Emim]BF4能有效解决沥青夹带沙土和残沙中含油的问题。     

水辅助溶剂法提取油砂中的沥青

开发了一种水辅助溶剂法从油砂中提取沥青的技术。该方法通过在油砂固相与有机溶剂间介入水层提取油砂中的沥青。以内蒙古扎赉特旗油砂矿为研究对象,考察了温度、剂砂质量比、提取时间、甲苯在复合溶剂中的含量及溶剂的种类与性质对沥青回收率高低的影响,结果表明：最佳提取条件为提取温度50℃,剂砂质量比1∶1,提取时间25min。沥青回收率与提取溶剂的性质紧密相关,水层介入有效降低了固体微粒组分在有机相中的含量,且便于后续的有机相与泥砂相的分离。通过对各种溶剂提取的沥青进行组分分析,发现各种溶剂对沥青提取能力的差异性源于溶剂的化学组成和结构不同。本文相关研究结果对溶剂法提取油砂中沥青技术及溶剂种类的选择具有指导作用。     

Water accumulation in the alcohol extraction of cottonseed

The critical moisture content of cottonseed flakes extracted with an aqueous alcohol solvent can be defined as that flake moisture level at which the flakes lose no moisture during extraction. This study shows that the critical moisture content for aqueous ethanol (92%, w/w) is 3%. For aqueous isopropanol (88%, w/w) this value is 6%. If the moisture contents of the flakes are above these levels, then the solvents pick up moisture. For moisture contents below this level, the flakes adsorb moisture and actually dry the alcohol. It is proposed that this latter capability can be used as a basis for a method to control water accumulation in aqueous alcohol solvent extractions.     

Evaluation of the diffusion coefficient of rapeseed oil during solvent extraction with hexane

The diffusion coefficient of rapeseed oil was determined from data obtained during time-varied solvent extraction experiments. The experiments were carried out in a Gülbaran extractor-diffuser with hexane as the solvent. A relationship was found between the slope of the diffusion line and the shape and size of the rapeseed particles. This relation can be used to calculate the diffusion coefficient. A diffusion coefficient of 3.4×10⁻⁸ cm²/s was determined from the experimental data.     

溶剂萃取法修复石油污染土壤

对溶剂萃取法修复石油类污染土壤的新技术做了较为全面的概述.首先,介绍了溶剂萃取技术的概念、机理和适用范围;其次,介绍了包括有机溶剂、表面活性剂、环糊精、超临界流体在内的萃取剂的研究进展;再次,阐述了影响溶剂萃取效率的因素和溶剂萃取的工艺条件;最后,对溶剂萃取技术的研究和应用做了展望.     

Comparison of processes for the supercritical carbon dioxide extraction of oil from soybean seeds

Three different process alternatives for the production of soybean oil by supercritical carbon dioxide extraction were analyzed. The first two processes were organized according to the classical scheme, based on high-pressure extraction followed by separation induced by pressure reduction. Different techniques were used to recover the solvent in these two schemes, in the liquid and in the gas phases, respectively. The third alternative was based on an isobaric scheme—the oil, extracted at high pressure, was separated by chainging the temperature in the separator. In a further improvement, a technique for the heat transfer network integration was added to all the process schemes. The different schemes were used to establish the process configuration that can produce a lower operating cost for soybean oil extraction. Operating costs were considered on an industrial scale to carry out a screening of the different alternatives. The operating cost of these plants were then compared with the hexane extraction process. A substantial reduction in the specific costs was obtained in the case of heat transfer integration, and the operating costs fell in the same range as conventional extraction plants.     

A twin-screw extruder for oil extraction: II. Alcohol extraction of oleic sunflower seeds

Our work is about the extraction of sunflower seed oil in a twin-screw extruder with or without the injection of 2-ethylhexanol and acidified 2-ethylhexanol. 2-Ethylhexanol is mixed with phosphoric acid. The oil recovery is increased to 90% by the co-injection of acidified alcohol. Mixing phosphoric acid with the alcohol enhances the lability of the oily spherosomes. Its addition increases the destruction of the membranes enveloping the lipid-containing organelles to release the oil more easily. Phosphoric acid exhibits an extracting and a degumming role. The best oil quality was obtained at a low extraction temperature (80°C), when 88% of the oil was removed. After alcoholic distillation, the oil exhibited a total acid value (mineral acidity plus organic acidity) of 4 mg KOH/g of oil and an organic phosphorus content below 30 ppm. This work was presented as an oral communication at the 2nd American Oil Chemists’ Society Europe Symposium, October 1–4, 1998, at Cagliari, Italy.     

人工神经网络模拟超临界萃取米槁精油

为了更好地研究超临界CO2流体萃取米槁精油过程,文中对该过程萃取动力学进行了分析,建立了3层反向传导的人工神经网络模型。以MATLAB软件为平台,编制模型程序。以温度、压力、超临界CO2流体流率和原料平均粒径为输入,以收率为输出对网络进行训练。训练好的模型可用于萃取过程预测,与实验结果比较,预测平均误差小于5.0%。说明该模型可以对萃取过程进行模拟和预测。     

国内外稠油和沥青VAPEX技术发展现状与分析

自1991年Roger Butler提出稠油和沥青的蒸汽萃取（VAPEX）技术以来,VAPEX已经成为一个非常有前途的开采工艺。最主要的原因是,相对于其它的采油工艺,VAPEX具有环境友好、成本低的特点。本文详细综述了国内外VAPEX技术最新发展现状,探讨了VAPEX开采稠油技术机理,评述了VAPEX技术优点及技术局限性,展望了VAPEX技术应用前景,提出了今后发展方向。     

桦甸油页岩的二级萃取溶解行为

以吉林桦甸油页岩为研究对象,通过二氯甲烷、石油醚两级萃取,对油页岩原矿、两级萃余物进行SEM扫描,对二氯甲烷萃取液、石油醚萃取液进行GC/MS检测,研究桦甸油页岩在两级溶液的溶解行为以及各级萃余物表面物理形貌。结果表明,随着萃取的加深,油页岩颗粒相对光滑的片层结构逐渐消失,颗粒粒径趋于细小,表面沟壑逐渐增多,后级萃取时液固接触面积增加。二氯甲烷和石油醚对油页岩中烷烃溶出能力较强。两级萃取物组分主要由C15～C28饱和烷烃构成。溶剂萃取法可以有效地提取油页岩中一类或相似的化合物群,对研究油页岩构成及提取高经济价值成分有重要意义。     

加拿大油砂溶剂抽提分离工艺的研究

对加拿大油砂进行了溶剂抽提分离试验,考察了石油醚、石脑油、甲苯、环己烷以及重整汽油对提取效果的影响,确定重整汽油为最佳抽提溶剂.综合考察了提取温度、溶剂与油砂体积比、提取时间以及搅拌速度等工艺操作条件对油砂沥青提取的影响,结果表明,在提取温度500℃,溶剂和油砂的体积比为1∶1,提取时间60 min,搅拌速度为80 r/min的条件下,油砂沥青提取率达到92.57%.     

双液相萃取棉籽油制备脂肪酸甲酯

以双液相萃取技术处理棉籽,在得到脱毒棉粕的同时得到含有高质量毛油的非极性相。以非极性相作为与甲醇进行酯交换反应的原料,得到脂肪酸甲酯和甘油。考察了非极性相溶剂石油醚与棉籽油的比例对酯交换转化率和洗涤粗产品用水量的影响,确定了石油醚与棉籽油的最佳质量比为3,在此条件下,洗涤用水量可降低一半。考察了醇油比、催化剂用量、反应温度、反应时间等参数对转化率的影响。应用正交实验的方法找出酯交换反应的适宜条件为：醇油比6：1,催化剂用量1.1％,反应温度60℃,反应时间120min。在此反应条件下,产物中脂肪酸甲酯的含量可达97.4％。     

Effect of adsorption and solvent extraction process on the percentage of carotene extracted from crude palm oil

Palm carotene was successfully concentrated from crude palm oil (CPO) by a batch adsorption process using a synthetic (polymer) adsorbent followed by solvent extraction. Carotene was concentrated to about 20,000 ppm, or about 33.3 times the original concentration in CPO. Carotene recovery varied from 16 to 74% depending on the process conditions. Adsorption times, isopropanol (IPA) extraction times, temperatures of adsorption and solvent extraction process, effect of agitation during IPA extraction process, and adsorbent lifespan were evaluated to determine their effects on the percentage of carotene extracted and carotene concentration. The minimum adsorption time required was 0.5 h. However, an adsorption time of 1.5 h gave a significantly higher carotene concentration than adsorption times of 0.5, 1.0, and 0.2 h. The IPA extraction time was determined based on the final carotene concentration desired. The suitable temperature for adsorption and solvent extraction process was 40°C. There was no significant difference in the percentage of carotene extracted and carotene concentration between the IPA extraction process with and without agitation.     

Solvent screening for non‐aqueous extraction of Alberta oil sands

Non‐aqueous extraction of bitumen from oil sands has the potential to reduce fresh water demand of the extraction process and eliminate tailings ponds. In this study, different light hydrocarbon solvents, including aromatics, cycloalkanes, biologically derived solvents and mixtures of solvents were compared for extraction of bitumen from Alberta oil sands at room temperature and ambient pressure. The solvents are compared based on bitumen recovery, the amount of residual solvent in the extracted oil sands tailings and the content of fine solids in the extracted bitumen. The extraction experiments were carried out in a multistage process with agitation in rotary mixers and vibration sieving. The oil sands tailings were dried under ambient conditions, and their residual solvent contents were measured by a purge and trap system followed by gas chromatography. The elemental compositions of the extraction tailings were measured to calculate bitumen recovery. Supernatants from the extraction tests were centrifuged to separate and measure the contents of fine solid particles. Except for limonene and isoprene, the tested solvents showed good bitumen recoveries of around 95%. The solvent drying rates and residual solvent contents in the extracted oil sands tailings correlated to solvent vapour pressure. The contents of fine solids in the extracted bitumen (supernatant) were below 2.9% for all solvents except n‐heptane‐rich ones. Based on these findings, cyclohexane is the best candidate solvent for bitumen extraction, with 94.4% bitumen recovery, 5 mg of residual solvent per kilogram of extraction tailings and 1.4 wt% fine solids in the recovered bitumen. © 2012 Canadian Society for Chemical Engineering     

Solvent extraction modeling of Ce/Eu/Y from chloride media using D2EHPA

End-of-life fluorescent lamps are becoming essential in the rare earths (REEs) field and suppose a feasible secondary source for getting them, reducing thus their supply risk. Considering the proved viability of the cationic extractants, the present study aims at establishing a solvent extraction model using di-(2-ethylhexyl)phosphoric acid (D2EHPA) not only based on the individual Ce, Eu, and Y behavior in chloride media, but also bearing in mind the competitive extraction of these metals in Ce/Eu/Y mixtures, depending on the media variables. Furthermore, the model allow determining the optimal REEs separation conditions. The results disclose that Y could be separated from the mixture using 0.1 mol/L D2EHPA, acidity above of 3 mol/L of protons and chloride concentrations higher than 4 mol/L.