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采用半微量相平衡测定装置和高精度密度-折光率测定仪,精确测定了CsCl-PEG 400-H2O三元体系在15,25和35℃3个温度下不同组分百分比溶液的折光率和密度数据,通过关联密度和折光率数据获得了CsCl在上述温度下的等温溶解度.对饱和体系的溶解度研究表明:在同一温度下CsCl的溶解度随聚乙二醇质量分数的增加而减小;在不同温度下CsCl的溶解度随温度的升高而增大.采用经验方程lnS=A1+A2ω2+A3ω2(2)+A4ω2(3)对饱和体系的溶解度进行了关联,效果较好.对不饱和体系的研究表明:当盐含量一定时,随着醇水比例的增加,体系的密度不断增大,折光率也随盐含量增加而增大;当醇水质量比一定时,体系的密度和折光率随盐含量的增加而增大,对不饱和体系的密度和折光率用经验方程Y=(A0+A1ω2+A2ω1+A3ω1ω2+A4ω2ω1(2))×exp[A5(ω1/ω3)+A6(ω1/ω3)2]进行拟合,拟合效果较好,同时给出了体系的盐析率曲线.本研究不仅为溶液化学提供了基础数据,也为混合溶液中盐和醇的分离纯化提供一种新的方法和思路,对CsCl进一步的应用、开发和研究具有一定的参考价值. 相似文献
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An experimental investigation on the influence of phenol on the solubility of CO2 in aqueous solutions of NaOH 下载免费PDF全文
Michael Jödecke Jianzhong Xia Álvaro Pérez‐Salado Kamps Gerd Maurer 《American Institute of Chemical Engineers》2015,61(9):2832-2840
Experimental results are presented for the solubility of CO2 in an aqueous solution of phenol and NaOH (molalties in water: phenol: 0.5; NaOH: 1.0) at (314, 354, and 395) K and pressures up to 10 MPa. The experimental work extends recent investigations on the influence of phenol as well as of (phenol + NaCl) on the solubility of CO2 in water. In contrast to those previous investigations, the strong electrolyte reacts with carbon dioxide and also with phenol. The experimental results are compared with predictions from a thermodynamic model. That model combines a model for the “chemical” solubility of CO2 in aqueous solutions of NaOH with a model for the “physical” solubility of CO2 in aqueous solutions of phenol. An extension is introduced to account for the chemical reaction between the weak acid phenol and the strong base sodium hydroxide. The prediction results nicely agree with the new experimental data. © 2015 American Institute of Chemical Engineers AIChE J, 61: 2832–2840, 2015 相似文献
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铷作为稀有碱金属常与钾共存,氯化铷在不同溶剂中的溶解度是对铷化合物结晶提纯的理论依据,因此,探究氯化铷在不同溶剂中的溶解规律对于实现铷钾分离具有指导意义。实验分别测定了常压条件下氯化铷在甲酸、冰乙酸、正丙醇和乙二醇中303.15—343.15 K条件下的溶解度。结果表明:氯化铷在上述4种有机溶剂中的溶解度均随温度的升高而增大,其中温度对氯化铷在甲酸中的溶解度影响最为明显;在4种溶剂中溶解度的排序为:甲酸乙二醇冰乙酸正丙醇,甲酸比较适合用于氯化铷的重结晶。同时对实验数据进行了拟合,实验数据与理论计算结果吻合,所得拟合方程可为氯化铷重结晶工艺路线的制定提供理论依据。 相似文献
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Stela Jokić Sandra Svilović Zoran Zeković Senka Vidović 《International Journal of Food Science & Technology》2011,46(5):1031-1037
The solubility of soybean oil in supercritical carbon dioxide has been determined in the pressure range of 100–300 bar and in the temperature range of 313–323 K. The obtained values (from 0.0005 to 0.02055 g L?1) have been correlated using four different empirical equations proposed correspondingly by Chrastil, del Valle and Aquilera, Adachi and Lu and Sparks et al. Since the Sparks et al. equation provided the lowest average absolute relative deviation (AARD) (10.25%) than other models in the examined experimental range, a modified equation of Sparks et al. model was developed for predicting the solubility of soybean oil in supercritical carbon dioxide as a function of temperature and density. An improved equation showed the lowest deviation (2.15%) between experimental data than the other empirical equations considered in this study. The proposed equation was also applied for correlating the solubility of linoleic acid (AARD was 2.40%). 相似文献
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Juan Milanesio Pablo Hegel Yaocihuatl Medina‐González Séverine Camy Jean‐Stéphane Condoret 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2013,88(3):378-387
BACKGROUND: Microorganisms have often been considered for the production of oils and fats as an alternative to agricultural and animal resources. Extraction experiments were performed using a strain of the yeast Yarrowia lipolytica (Y. lipolytica), a high‐lipid‐content yeast. Three different methods were tested: Soxhlet extraction, accelerated solvent extraction (ASE) and supercritical carbon dioxide (SCCO2) extraction using ethanol as a co‐solvent. Also, high pressure solubility measurements in the systems ‘CO2 + yeast oil’ and ‘CO2 + ethanol + yeast oil’ were carried out. RESULTS: The solubility experiments determined that, at the conditions of the supercritical extractor (40 °C and 20 MPa), a maximum concentration of 10 mg of yeast oil per g of solvent can be expected in pure CO2. 10% w/w of ethanol in the solvent mixture increased this value to almost 15 mg of yeast oil per g of solvent. Different pretreatments were necessary to obtain satisfactory yields in the extraction experiments. The Soxhlet and the ASE method were not able to complete the lipid extraction. The ‘SCCO2 + ethanol’ extraction curves revealed the influence of the different pretreatments on the extraction mechanism. CONCLUSION: Evaluating the effectiveness of a given pretreatment, ASE reduced the amount of material and solvent used compared with Soxhlet. In all three cases, the best total extraction performance was obtained for the ethanol‐macerated yeast (EtM). Addition of ethanol to the solvent mixture enhanced the oil solubility. Oil can be extracted from Y. lipolytica in two different steps: a non‐selective ethanol extraction followed by TAG‐selective SCCO2 purification. © 2012 Society of Chemical Industry 相似文献
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