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1.
Nine non‐halogenated solvents for the extraction of fat from meat and bone meal (MBM) were evaluated by the accelerated solvent method. Yields of about 15% were obtained with all solvents, but n‐hexane was found to be the most suitable extraction solvent, because it is relatively cheap and has a low boiling point. Fat was also extracted from MBM on preparative scale (600 g) by immersion, and the extracted material was analysed for impurities that could affect the subsequent transesterification. The extracted material was converted into fatty acid methyl esters (FAME) via a two‐step process. For further purification, the raw FAME were distilled under reduced pressure. The final product was analysed according to the European specification for biodiesel (EN 14214). Almost all of the values were within the specifications, except the cold‐temperature behaviour and the oxidation stability. All in all, extracted fat from MBM is a potential feedstock for the production of biodiesel.  相似文献   

2.
The process of soybean-protein isolation, comprising extraction in dilute calcium hydroxide and precipitation with hydrochloric acid at pH 4.5, was evaluated from the viewpoint of the effect of processing conditions on yields and product purity. The course of extraction and the effect of particle size and agitation indicate that the process is quite rapid even when coarse meal is treated under mild agitation. The heattreatment history of the meal is the main factor governing the extraction and isolation yields. The precipitation yield is unaffected by temperature. Two steps of curd washing were found to suffice for maximum product purity. The purity is also improved considerably by preliminary sifting of the meal.  相似文献   

3.
The preparation of biodiesel and nontoxic cottonseed meal from cottonseed by two‐step two‐phase solvent extraction (TS‐TSE) combined with the transesterification reaction was investigated. The TS‐TSE process could significantly reduce the biodiesel production costs when compared with the two‐phase solvent extraction (TSE) process due to the reduction in methanol. A series of experiments was conducted to evaluate the effects of some factors on the fatty acid methyl ester (FAME) yield and free gossypol (FG) content. These conditions resulted in a maximum FAME yield and reduced the FG content in the cottonseed meal far below the Food and Drug Administration standard. The nontoxic cottonseed meal could be used as animal feed protein source.  相似文献   

4.
Vegetable oils are typically extracted with hexane; however, health and environmental concerns over its use have prompted the search for alternative solvents. Mustard oil was extracted with isopropyl alcohol (IPA) to produce an IPA‐oil miscella suitable for industrial applications. Single‐stage extraction resulted in 87.6 % oil yield at a 10:1 (v/w) IPA/flour ratio. Multiple‐stage extraction resulted in higher extraction efficiency with lower IPA use. Four‐stage cross‐current extraction at an IPA/flour ratio of 2:1 (v/w) per stage resulted in 93.7 % oil yield. At 45 °C, a 91.5 % oil yield was achieved with three‐stage extraction using a 2:1 (v/w) IPA/flour ratio. Any changes to the pH of the mixture resulted in reduced oil yield. Water also reduced the extraction efficiency. The azeotropic IPA solution containing 13 % water extracted ~40 % less oil than did dry IPA in both single and multiple‐stage extractions. Some polar compounds were also extracted, including sugars; however, protein extraction was negligible. The protein left in the extracted meal was not degraded or lost during the extraction. The results suggest that IPA is an excellent solvent for mustard oil, but water content exceeding 5 % in the solvent adversely affects the oil extraction and reuse of the IPA.  相似文献   

5.
Modern processing plants extract soyabean oil by solvent liquid transfer. Soyabeans are cleaned, cracked, dehulled and conditioned into a thin flake before they enter the extractor. Extraction is by successive, countercurrent washes of hexane solvent. The extracted flakes are then carried by a sealed conveyor to be desolventized in enclosed vessels by application of jacket and sparge steam. Hexane is removed from the oil in rising film evaporators and with final vacuum distillation. Hexane is recovered from the meal and the oil in atmospheric condensers. The complete plant installation is explosion-proof and all equipment is sealed and vapor-proof. For a good operation, soyabeans must be clean, undamaged and at the correct moisture and temperature. Parameters of the process in the plant are: tonnage, hexane loss and energy usage. Oil quality is measured in terms of free fatty acids, absence of residual hexane and crude oil color. Meal quality is determined by residual oil, moisture, protein, urease activity protein solubility and mesh size in the finished product. Innovations at modern plants include degumming of the oil, lecithin drying and blending and production of soyabean meal with high protein solubility for human consumption.  相似文献   

6.
葡萄籽中原花青素的提取与纯化   总被引:1,自引:0,他引:1  
文章以青岛大泽山葡萄籽为原料,利用溶剂提取法来提取活性物质原花青素,通过正交实验考察了提取溶剂、粉碎粒度、料液比三因素对提取效果的影响。获得了较优的提取条件:丙酮-水体系的最佳提取条件为:葡萄籽粒度60-80目,丙酮浓度40%,料液比1:6(g·mL^-1)。实验还对粗产物进行了提纯,提纯后的产品纯度平均为93%,最高可达96.78%;提纯率平均为32.36%,最高可达42.69%。并在此基础上考察了微波辅助浸提对提取效果的影响。  相似文献   

7.
芴溶解度的测定及溶液结晶法提纯芴的工艺研究   总被引:1,自引:1,他引:1  
在测定芴在甲醇、乙醇、正丁醇、甲苯、邻二甲苯中溶解度的基础上,确定正丁醇是溶液结晶法提纯芴的合适溶剂。介绍了采用溶液结晶法对工业芴的提纯分离的工艺过程及不同结晶条件对产品收率和纯度的影响,确定了利用溶液结晶提纯芴的最佳工艺条件,经提纯后可使芴的纯度由89.0%提高到96.6%或由95.0%提高到97.1%。  相似文献   

8.
The main goal of this work is to evaluate the extraction of sunflower oil from enzyme-treated collets using ethanol and isopropanol (IPA) as solvents. The sunflower collets are pretreated with the multienzyme complex Viscozyme L prior to solvent extraction by the Soxhlet method. The influence of the moisture content of the collets, pretreatment, processing time, and solvent type on the amount of total extracted material and the oil extraction efficiency is studied. Some quality parameters such as phospholipid content of the oil and chlorogenic acid content of the residual meal are also analyzed. At low moisture content (7%) the solvents exhibit similar oil extraction ability (98–99%), but with increasing moisture the extraction efficiency of ethanol decreases to about 85%, while no significant differences are observed for IPA. The enzymatic treatment increases the extraction efficiency for all times, especially for ethanol. It is observed that IPA is more efficient in the extraction compared to ethanol, and the amount of nonlipid material is reduced by ≈70%. In addition, the oil extracted with IPA have lower phospholipid content and the residual meal presents a higher chlorogenic acid content. Practical Applications:This work would contribute toward the use of green solvents in the extraction of sunflower oil from collets. Ethanol and isopropanol, used as solvents, present attractive advantages, including low toxicity, good operational security, as well as being obtained from a renewable source. The obtained data provide up-to-date information on the use of these alcohols in the extraction of sunflower oil from collets and the influence of operating conditions, such as moisture content, enzymatic pretreatment of the collets, and the extraction time. Information about oil and meal quality is also reported.  相似文献   

9.
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.  相似文献   

10.
十三碳二元酸的精制提纯是正构烷烃生物发酵法制备十三碳二元酸的重要环节,关系到该工艺的总收率和产品质量。溶剂法的关键是选择适宜的溶剂,醇类溶剂在精制条件下易与二元酸发生酯化反应,降低收率,影响产品纯度;水相法不能很好地除去残油、色素及菌体等,制得的产品纯度、外观及晶体粒度都差,但设备投资少,操作过程简单、安全、对环境污染小;酯化法对原料纯度要求不高,精制产品的纯度可达到99%以上,在某些特殊情况下或制备高纯度产品时是其它方法不能替代的。  相似文献   

11.
Advantages of the Rotocel system for cottonseed cake extraction may be summarized in the following manner:
  1. Economical conversion to solvent extraction is possible by utilizing existing or reconditioned screw-press equipment.
  2. Conditioner and flaking rolls are not required for this process.
  3. The electrical power requirements for the cake preparation and extraction are less than the power reduction when converting from straight pressing to a prepress operation. This results in a net savings in power consumption.
  4. Vapor scrubbers used in conventional plants are not required in this process.
  5. Efficient extraction at low solvent ratios keeps the steam requirement of this process to a minimum.
  6. Low residual oil in extracted meal accomplished by this process yields a maximum product value per ton of seed.
  7. The low temperature vapor desolventizer eliminates discolorization and protein degradation of the cake granules during the desolventizing step.
  相似文献   

12.
低温煤焦油中特定芳烃组分的选择性分离   总被引:1,自引:1,他引:0       下载免费PDF全文
以研究低温煤焦油中特定芳烃组分的选择性分离为目标, 通过预处理分离酚类化合物和富集特定芳烃组分, 采用多元溶剂萃取方法选择性分离芳烃和非芳烃组分, 采用Hansen溶度参数理论进行多元溶剂的设计和萃取条件的优化。结果表明, 溶剂对原料焦油的选择性随Hansen溶度参数“距离”(Ra)增加而增大, 萃取能力则相反。研究得到的多元萃取剂是含水量为体积分数6%的N,N-二甲基甲酰胺溶液, 优化萃取条件是温度25℃、剂/油比6:1。萃余物经多次萃取进一步分离芳烃组分, 萃出物经甲酰胺多次萃取以分离出杂环化合物和极性组分。芳烃组分在最终分离产物中的质量分数为94%, 其总萃取收率为95%。另外非芳烃化合物、杂环化合物和其他极性组分也在本过程中得到了有效富集。  相似文献   

13.
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  相似文献   

14.
将超声波提取技术与丙醇-硫酸铵双水相分离技术进行耦合,从核桃叶中提取黄酮类化合物,提取率为13.9%。与传统的有机溶剂回流提取法(提取率14.2%)相比,该法的提取率略低,但提取过程中体系的温度不会大幅度升高,可有效地保持黄酮的生物活性,而且双水相分离使黄酮的纯度得以提高。  相似文献   

15.
刘敏  张宏宇等 《山东化工》2001,30(5):35-36,38
叙述了C4分离装置萃取剂再生系统的改造内容,经过工艺流程和产品纯度及收率对比分析,可以看出,改造是成功的。  相似文献   

16.
Supercritical carbon dioxide extraction to separate phytosterol esters from fatty acid esters and tocopherols was simulated and optimized using the group contribution equation of state. Experimental extraction data at 328 K, pressures ranging from 200 to 280 bar and solvent‐to‐feed ratio around 25, was employed to verify the performance of the thermodynamic model. The raw material is the product obtained after a two‐step enzymatic reaction carried out on soybean oil deodorizer distillates, and contains mainly fatty‐acid ethyl esters, tocopherols and phytosterol esters. The extraction process was simulated using model substances to represent the complex multicomponent feed material. Nonlinear programming techniques were applied to find out optimal process conditions for a steady‐state countercurrent process with partial reflux of the extract. The process optimization procedure predicts that a product with 94.2 wt % of phytosterol ester purity and 80% yield could be achieved. © 2009 American Institute of Chemical Engineers AIChE J, 2009  相似文献   

17.
反应精馏和液液萃取结合合成二甲氧基甲烷   总被引:3,自引:0,他引:3  
以对甲苯磺酸为催化剂,以甲醇、甲醛为原料,采用反应精馏合成二甲氧基甲烷,二甲氧基甲烷的质量分数达到92%以上;采用液液萃取法对产物进一步提纯,研究液液萃取过程中,转速、搅拌时间、静置时间、溶剂比等因素对分离过程的影响,二甲氧基甲烷的收率可以达到90%以上;经一级萃取,二甲氧基甲烷的纯度可达到97%以上,二级萃取纯度可达到99.3%以上,萃取剂经处理,可循环使用;并对结果进行关联,关联和实验结果平均相对误差均小于1%,其结果为进一步放大实验研究提供依据。  相似文献   

18.
Considering that the on-line measurement and automatic control of element component content (ECC) are dif-ficult to perform in rare earth cascade extraction process, the ECC distribution profile is dyn...  相似文献   

19.
Fine-ground rapeseed meal can be fractionated by liquid cyclone processes into flour and hull fractions. The process can be applied to expeller meal or to the marc after solvent extraction. A nonpolar solvent such as hexane is particularly effective because residual oil in the products is also substantially reduced. The flour, obtained in yield of about66% of the meal, contained over 45% protein and 5-8% of crude fiber. Rapeseed meal is relatively low in digestible energy and the flour fraction would have greater application as a protein supplement in pig and poultry feeds.  相似文献   

20.
A study was carried out to determine the effect of different solvents on the extraction of protein fractions in beans. Black bean protein was extracted with the following solvents: distilled water, 0.01 M sodium hydroxide, 0.05 M sodium chloride, and 70% ethanol. By using each solvent under different conditions, it was possible to establish the optimum ones for the best extraction and fractionation of proteins from leguminous seeds. These conditions were the following: one hour agitation at room temperature, three successive extractions with the same solvent, and a ratio of solid to solvent of 1:20 W/V. The effect of 24 different sequences of solvents upon the extraction of protein was also investigated. From the extraction point of view, the best sequence of solvents for extracting the protein was that where NaOH constituted the first solvent used; this sequence, however, has the disadvantage of extracting all the protein from the seed, making it impossible to separate other protein fractions by another solvent. If the purpose of the extraction is to separate different protein fractions, the best sequence of solvents is distilled water or sodium chloride in the first place, followed by ethanol and sodium hydroxide. The need for using standardized methodology for the fractionation of protein from seeds in order to obtain comparable data between research laboratories is emphasized.  相似文献   

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