共查询到18条相似文献,搜索用时 140 毫秒
1.
利用超临界流体CO2反胶团-络合萃取食品中痕量重金属铅、汞和砷,通过正交实验考察了萃取压力、萃取温度、萃取时间和反胶团AOT浓度对痕量重金属萃取率的影响。确定最佳萃取工艺为:萃取压力20 MPa、萃取温度45℃、萃取时间90 min、反胶团AOT浓度0.1 mol.L-1,此时,重金属铅、汞、砷的萃取率分别为93.50%、95.36%、90.47%。表明超临界流体CO2络合萃取时加入反胶团能明显提高痕量重金属的脱除率,萃取效果优于超临界流体CO2反胶团萃取和超临界流体CO2络合萃取。 相似文献
2.
3.
4.
5.
6.
7.
反胶团萃取蛋白质技术的新进展 总被引:2,自引:0,他引:2
反胶团液-液萃取技术具有条件温和、高选择性、易放大等优点,是一种应用前景极好的生化分离方法。本文介绍反胶团的性质、萃取原理,并着重分析了制约反胶团萃取技术实用化的各种因素及研究现状,评述其工业应用前景。 相似文献
8.
9.
10.
11.
H. K. Mangold 《Journal of the American Oil Chemists' Society》1983,60(2):226-228
Soybean oil and numerous other vegetable oils can be extracted from crushed seeds by means of liquefied gases or supercritical
fluids. The oils are recovered by lowering the pressure or increasing the temperature, or both. Supercritical carbon dioxide
is ideally suited for the food industry as it is nontoxic and nonflammable. Moreover, it can be removed easily from the oil
as well as the meal. The oils extracted with supercritical carbon dioxide contain much lower proportions of phospholipids
than those obtained by conventional processing with hexane. The addition of acetone or another carrier or entrainer aids in
the fractional extraction of lipids differing in polarity. The range of applicability of liquefied gases and supercritical
fluids in the extraction and fractionation of lipids should be explored further to develop industrial processes using these
solvents. 相似文献
12.
Eduardo Vyhmeister Humberto Estay Julio Romero Francisco Cubillos 《Chemical Engineering Communications》2013,200(5):644-657
Supercritical fluid and membrane technology coupling is a relatively new concept applicable to solvent separation and solute extraction. In these processes a hydrophobic or hydrophilic macroporous membrane is used as a two-different-nature solutions contactor. This methodology is an alternative to conventional liquid solution supercritical fluid extraction processes, which are associated with high investment costs. In the present work, a membrane-based supercritical fluid extraction module is modeled, simulated, and optimized as an independent industrial-scale operational unit. UniSim design suite R390 software from Honeywell was used as the platform for the simulation. Acetone and ethanol literature extraction results and methanol experimental extraction results (27.6% to 14.5% with a 10 wt.% aqueous solution; 7.1% to 5.9% with a 500 ppm aqueous solution) were used for validation of the model and definition of the semi-empirical equation parameters. The generated industrial-scale system optimization, which used a modular membrane arrangement, was strongly dependent on thermodynamic, economic, and energetic variables (higher mass transfer resistance in the carbon dioxide phase increased the number of membranes needed; process feasibility was affected by the number of membrane units, carbon dioxide flow rate, and product added value; compression energy requirements affected the optimization result). The modeled system proved to be an important aid in the design, scaling, and optimization of systems that use membranes as phase contactors in liquid solution supercritical carbon dioxide extraction. 相似文献
13.
Supercritical extraction (SE) is a separation technique utilizes near or above critical properties of the solvents. In this technique, modeling of yield and solubility of materials are crucial points in supercritical fluid extraction processes. Generally, mathematical modeling of the supercritical oil extraction is a very difficult task since a highly nonlinear relation exists between process variables and solubility. Considering these facts, in the present study, a trainable cascade-forward back-propagation network (CFBPN) was proposed to correlate the yield of spearmint oil extracted by supercritical carbon dioxide. The results revealed the applicability of the proposed model to correlate the yield of spearmint oil extraction with an acceptable level of accuracy. Finally, the obtained results were compared to mathematical models namely Goodarznia & Eikani and Kim & Hong. The comparison between the results of proposed network and mathematical models demonstrated a better predictive capability of the proposed network. 相似文献
14.
超临界流体技术及其在生物工程中的应用 总被引:23,自引:0,他引:23
介绍了在生物工程有着广泛的应用前景的多种超临界流体技术,包括提取生物活性物质的超临界流体萃取,超临界条件二氧化碳中制备手性药物制备和淀粉水解制取葡萄糖的非水酶催化反应,超临界水条件下纤维素水解制备葡萄糖,超临界流体中的细胞破碎,制备缓释药物和色说载体的超临界流体溶液快速膨胀和气体抗溶剂结晶和沉淀技术。 相似文献
15.
采用超临界二氧化碳(ScCO2)作为反应介质进行乳液聚合是高分子材料合成与加工的一种绿色技术,具有无毒无害,聚合反应速率快,产物易分离和高选择性等特点。介绍了ScCO2乳液聚合技术的发展状况及其国外最新进展,指出ScCO2技术与乳液聚合相结合制备高分子合成材料,可避免使用有毒或挥发性有机溶剂、减少环境污染、提高材料性能和简化加工生产工艺,具有广阔的应用前景。 相似文献
16.
Effects of supercritical carbon dioxide on waste banana peels for heavy metal removal 总被引:1,自引:0,他引:1
Juliana Q. Albarelli Rodrigo B. Rabelo Diego T. Santos Marisa M. Beppu M. Angela A. Meireles 《The Journal of Supercritical Fluids》2011,58(3):343-351
The effects of supercritical carbon dioxide (CO2) on waste banana peels for copper adsorption were evaluated. Supercritical CO2 was employed both in a solvent extraction for antioxidant compound recovery and in an emerging biomass treatment to increase the subsequent heavy metal-removal step; the latter is termed “explosion with supercritical CO2”. This lignocellulosic biomass was analyzed before and after being subjected to both processes by scanning electron microscopy and X-ray patterning. Thermal gravimetric and differential scanning calorimetry analyses were performed to understand the different effects of supercritical carbon dioxide employed in these two processes on banana peels. The explosion with supercritical CO2 process resulted in a more pronounced effect on the vegetable structure. Nevertheless, no increase in the copper-removal capacity was achieved. The adsorption studies showed similar behaviors for fresh and extracted samples, demonstrating that banana peels previously extracted with supercritical CO2 retained their adsorption capacity for subsequent heavy metal removal. 相似文献
17.
18.
K. Sawada D. Terada T. Yamaoka S. Kitamura T. Fujisato 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(6):943-949
BACKGROUND: The objective of this work was to decellularize artificial tissue without using surfactant solutions. For this purpose, supercritical carbon dioxide was used as the extraction medium. RESULTS: Supercritical carbon dioxide containing a small amount of entrainer was a suitable medium to extract both cell nuclei and cell membranes from artificial tissue. Under gentle extraction conditions (15 MPa, 37 °C), cell nuclei were satisfactorily extracted from tissue within 1 h. In contrast, the efficiency of phospholipid removal depended strongly on the transfer rate of carbon dioxide in the interior of the tissue. Mechanical strength of tissue was not decreased even with prolonged treatment. CONCLUSION: Acellular artificial tissues could be prepared quickly by treatment with a carbon dioxide/entrainer system. The prepared acellular tissue could be obtained in absolutely dry condition. This is advantageous from the viewpoint of long‐term preservation without putrefaction and contamination. Copyright © 2008 Society of Chemical Industry 相似文献