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Michael Gyamerah John Glover 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1996,66(2):145-152
A continuous pilot plant was constructed for fermentation production of ethanol, using liquid–liquid extraction to remove the product and with recycle of the fermented broth raffinate. The plant was operated for up to 18 days with feed glucose concentrations in the range 10·0–45·8% (w/w). The solvent was n-dodecanol and immobilised yeast was used to overcome the problem of emulsification. The concentration of by-products in the fermented broth had no adverse effect on the rate of ethanol production. A mathematical model to predict the time required for achievement of 99% of the steady-state by-products concentrations was shown to be in good agreement with the experimentally determined concentration of the main by-product, glycerol. At a feed glucose concentration of 45·8% (w/w), the aqueous purge was equivalent to 2·8 m3 of effluent per m3 of ethanol produced and represented a 78% reduction in the volume of the aqueous purge compared with using a feed containing 10% (w/w) glucose. 相似文献
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综述了溶剂萃取净化法在湿法磷酸清洁生产中的应用和工艺,详细评述了国外各公司溶剂萃取法的工艺流程及我国在这方面的进展,并指出其发展趋势。 相似文献
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生物碱提取与纯化技术应用进展 总被引:11,自引:0,他引:11
生物碱是许多中药的有效成分,提取与纯化是生物碱制备的关键环节。目前较为常用的提取方法有煎煮、浸渍、回流和渗漉;纯化方法有有机溶剂萃取、色谱和树脂吸附。超声、微波辅助提取、超临界流体萃取、分子印迹和膜分离等技术的应用使生物碱制备向高效节能方向发展。本文综述了生物碱制备常用的提取与纯化工艺与新技术的应用进展,分析了它们的原理及优缺点并探讨了发展前景。 相似文献
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Gregory John Griffin Li Shu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(5):505-511
Research was performed to determine whether it was technically feasible to use boronic acid extractants to purify and concentrate the sugars present in hemicellulose hydrolysates. Initially, five types of boronic acids (phenylboronic acid, 3,5‐dimethylphenylboronic acid, 4‐tert‐butylphenylboronic acid, trans‐β‐styreneboronic acid or naphthalene‐2‐boronic acid) dissolved in an organic diluent (Shellsol® 2046 or Exxal® 10) containing the quaternary amine Aliquat® 336 were tested for their ability to extract sugars (fructose, glucose, sucrose and xylose) from a buffered, immiscible aqueous solution. Naphthalene‐2‐boronic acid was found to give the greatest extraction of xylose regardless of which diluent was used. Trials were then conducted to extract xylose and glucose from solutions derived from the dilute acid hydrolysis of sugar cane bagasse and to then strip the loaded organic solutions using an aqueous solution containing hydrochloric acid. This produced a strip solution in which the xylose concentration had been increased over 7× that of the original hydrolysate while reducing the concentration of the undesirable acid‐soluble lignin by over 90%. Hence, this process can be exploited to produce high concentration xylose solutions suitable for direct fermentation. Copyright © 2004 Society of Chemical Industry 相似文献
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简要介绍了乙醇和水分离的方法,设计了蒸馏和萃取精馏相结合分离乙醇和水的工艺,并模拟该工艺的分离结果,以乙二醇为萃取剂进行了萃取精馏试验,结果表明以乙二醇为溶剂萃取分离乙醇和水,分离后乙醇的质量含量可提高到99.7%,与蒸馏过程相比节能20%~30%。 相似文献
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水飞蓟素提取纯化工艺研究 总被引:2,自引:0,他引:2
水飞蓟素是一种重要的医药原料,本文对提取纯化水飞蓟素的多种工艺进行了研究,最终得出了一种适合工业化生产的新工艺,提高了水飞蓟素的提取率和溶剂回收率,降低了生产成本。 相似文献
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荷叶总生物碱的提取与纯化研究 总被引:4,自引:1,他引:4
用乙醇提取荷叶中总生物碱,用大孔吸附树脂进行纯化。探讨了提取剂、温度、时间、提取次数等因素对提取率的影响。实验表明,最佳提取条件为:以90%乙醇为提取剂,在90℃下,按料液比为1∶15和1∶10各提取1次,每次2 h,提取率为94.6%,得率为23.83 mg/20 g。D106大孔吸附树脂分离,乙醇洗脱(流速1~2 mL/m in),纯度达93.12%以上。 相似文献
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Acidic ethanol extraction of cottonseed 总被引:1,自引:0,他引:1
R. J. Hron Sr. G. Abraham M. S. Kuk G. S. Fisher 《Journal of the American Oil Chemists' Society》1992,69(9):951-952
Ethanol (EtOH) is being evaluated as an alternate solvent to hexane for the extraction of glanded cottonseed. Hot EtOH, needed
for efficient oil and aflatoxin extraction, binds gossypol to protein. However, this binding can be minimized by acidifying
aqueous EtOH with a tribasic acid, such as phosphoric or citric. While this solvent extracts oil and gossypol, it does not
affect EtOH’s ability to extract aflatoxin. The defatted cottonseed meals produced from this process contained 0.03% total
gossypol (which is lower than meal prepared by most other processes) and the aflatoxin content was reduced from 69 to 2.9
ppb. These are preliminary results and additional research is needed to determine commercial feasibility. The removal of essentially
all gossypol from an extracted meal has the potential to expand the use of cottonseed meal as a feed, increasing its value
to both the cotton farmer and the seed processor.
Presented in part at the 40th Oilseed Processing Clinic, March 4, 1991, New Orleans, LA. 相似文献
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为了提高南瓜多糖的提取率,采用冷冻法对南瓜进行前处理,通过正交实验确定了南瓜多糖提取的工艺参数,采用凝胶层析法对南瓜多糖进行了纯化并测定其分子量,采用了红外光谱对南瓜多糖进行了结构分析。实验结果表明,采用冷冻预处理后,南瓜多糖的提取率增加了77%;正交实验确定的南瓜多糖的优化工艺参数为:提取温度65℃,提取时间2 h,料液比1∶16;南瓜粗多糖经SephadexG-200凝胶层析柱后分为2个色谱峰,其平均分子量分别约为21 400和57 500;红外光谱分析显示,南瓜多糖为含有环状结构的多糖。 相似文献
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Weiwei Wang Chu Yong Cheng 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(10):1237-1246
The technologies of solvent extraction, ion exchange, and liquid membrane for the separation and purification of scandium are reviewed. Acidic and neutral organo‐phosphorus extractants are most widely used in practice, with high extraction efficiencies. Their disadvantages originate from the high stripping acidity required for the former and the poor selectivity for the latter. Carboxylic acids, amines, and acidic β‐diketone have also been widely used to extract scandium from solutions with low acidities. Mixed extractants or synergistic systems for the solvent extraction of scandium have been developed. Extraction efficiencies are influenced by extraction conditions such as aqueous matrixes and acidities, types of diluents and A/O ratios. Scandium(III) extractions are interfered with by commonly associated elements such as iron(III), zirconium(IV), titanium(IV), thorium(IV), yttrium(III) and lanthanides(III). The advantages and disadvantages of applications of ion exchange and liquid membrane technologies for scandium recovery are reviewed and compared with solvent extraction. Copyright © 2011 Society of Chemical Industry 相似文献