齐墩果酸在超临界CO2中的溶解度研究

采用静态平衡差重法测定了齐墩果酸在超临界CO2中各个状态点的溶解度,考查了温度、压力、密度等因素对齐墩果酸在超临界CO2中溶解度的影响,并采用Chrastil模型对实验数据进行分析计算。实验结果表明：齐墩果酸在超临界CO2中的溶解度随着压力的增加而增加,20MPa条件下的密度与溶解度符合一定的函数关系。     

聚苯乙烯在超临界丙烷中的溶解度测定

从20世纪70年代末兴起超临界流体技术以来,人们已经对超临界萃取进行了大量的研究．近几年来,研究的热点转向超临界的粒子制备、物质的超临界处理、超临界聚合和聚合物的超临界分离．而在所有的超临界流体技术研究中,一个很重要的基础问题就是需要了解和预测超临界流体的     

Solubility of red palm oil in supercritical carbon dioxide: Measurement and modelling

The solubility of red palm oil(RPO) in supercritical carbon dioxide(scCO_2) was determined using a dynamic method at 8.5–25 MPa and, 313.15–333.15 K and at a fixed scCO_2 flow rate of 2.9 g·min~(-1) using a full factorial design. The solubility was determined under low pressures and temperatures as a preliminary study for RPO particle formation using scCO_2. The solubility of RPO was 0.5–11.3 mg·(g CO_2)~(-1) and was significantly affected by the pressure and temperature. RPO solubility increased with pressure and decreased with temperature. The Adachi–Lu model showed the best-fit for RPO solubility data with an average relative deviation of 14% with a high coefficient of determination, R~2 of 0.9667, whereas the Peng–Robinson equation of state thermodynamic model recorded deviations of 17%–30%.     

超临界流体色谱法测定固体在二氧化碳中的溶解度

开发了一种测定超临界二氧化碳中大分子溶质的溶解度的方法。这一方法将微型超微界流体萃取直接与超临界色谱相耦合，超临界流体色谱采用ＦＩＤ作为检测器。实验中两者具有同一压力、温度及同样的ＣＯ２流速度。     

Simple three parameter equations for correlating liquid phase compositions in subcritical and supercritical systems

Two Chrastil type expressions have been developed to model the solubility of supercritical fluids/gases in liquids. The three parameter expressions proposed correlates the solubility as a function of temperature, pressure and density. The equation can also be used to check the self-consistency of the experimental data of liquid phase compositions for supercritical fluid–liquid equilibria. Fifty three different binary systems (carbon-dioxide + liquid) with around 2700 data points encompassing a wide range of compounds like esters, alcohols, carboxylic acids and ionic liquids were successfully modeled for a wide range of temperatures and pressures. Besides the test for self-consistency, based on the data at one temperature, the model can be used to predict the solubility of supercritical fluids in liquids at different temperatures.     

Solubility of red pepper (C<Emphasis Type="Italic">apsicum annum</Emphasis>) oil in near- and supercritical carbon dioxide and quantification of capsaicin

Red pepper oil was extracted using near- and supercritical carbon dioxide. Extraction was carried out at pressures ranging from 10 to 35 MPa and temperatures from 30 to 60 °C, with a CO₂ flow rate of 24.01 g/min using a semi-continuous high-pressure extraction apparatus. The duration for extraction was 2 h. The highest oil yield was found at high pressure and temperature. The highest solubility of oil (1.18 mg/g of CO₂) was found at 35 MPa and 60 °C. The solubility data of red pepper oil in near- and supercritical CO₂ were fitted in Chrastil model. The fatty acid composition of red pepper oil was analyzed by gas chromatography (GC). Linoleic acid was found to be the major fatty acid in the oil. Capsaicin was quantified in different extracts by high performance liquid chromatography (HPLC). The highest capsaicin yield was found at 35 MPa and 60 °C.     

超临界CO_2及超临界CO_2/乙醇中磷脂酰胆碱的溶解度

利用动态法测定了磷脂酰胆碱(PC)在超临界CO2(SC-CO2)及超临界CO2/乙醇体系中的溶解度。在15~30 MPa压力(p)、313~343 K温度(T)条件下,PC在SC-CO2中的溶解度为x1(PC)=10-6~10-5,在SC-CO2/乙醇多元体系中,PC溶解度x2(PC)可提高至10-4。PC的溶解度与c(CO2)(d)、x(CH3CH2OH)(c)呈指数相关性。根据缔合反应规则,建立了质量作用模型x1(PC)=d3.89e(-2383.63/T-41.64)、x2(PC)=d3.17c0.36e(-1748.03/T-33.73),分别关联PC在SC-CO2、SC-CO2/乙醇中的溶解度,模型计算结果与溶解度实验数据较好吻合,关联误差(AARD)分别为4.31%、3.78%。     

Determination and calculation of solubility of bisphenol A in supercritical carbon dioxide

Supercritical fluid technology (SFT) as a new technique is very important for clean environment and removal of chemical pollutants. The lack of solubility data of solid solute in certain supercritical fluid is a great obstacle to the successful implementation of SFT. In this work, the solubility of bisphenol A in supercritical carbon dioxide was determined by the dynamic method at the temperatures ranging from 308 to 328 K and pressure range of 11.0–21.0 MPa. The effects of temperature and pressure on solubility were analyzed according to molecular motion theory. The solubility data were correlated using eight different semi-empirical models (Chrastil, Adachi–Lu, Kumar–Johnston, Tang, Sung–Shim, Bartle, Méndez Santiago–Teja and Yu). The comparison between different models was discussed. The thermodynamic properties (total enthalpy ΔH, enthalpy of sublimation Δ_subH and enthalpy of solvation Δ_solvH) of the solid solute were obtained.     

Solubility of astaxanthin in supercritical carbon dioxide

The solubility of astaxanthin in carbon dioxide was measured under supercritical conditions of a pressure range from 80 to 300 bar, and temperature range from 303 to 333 K, by using a dynamic flow-type. The solubility of astaxanthin increasing from 0.42×10⁻⁵ to 4.89×10⁻⁵ with higher temperature and pressure maintains certain density of supercritical carbon dioxide. The solubility data obtained were applied to the Chrastil model, based on the density of carbon dioxide. The data fitted well with the Chrastil model at most experimental conditions.     

阿昔洛韦在超临界CO2中的溶解度与关联

药物微粒化可改善其溶出度,提高生物利用度。为应用超临界流体技术制备阿昔洛韦(Acyclovir)微粒,用静态法测定了在313．15～413．15K,10．0～30．0MPa下阿昔洛韦在超临界CO2中的溶解度。阿昔洛韦的溶解度较小,在10^-5～10^-7(摩尔分率)之间,溶解度随着温度和压力的升高而增大,不存在文献报道的反向区。采用P-R方程对溶解度数据进行关联,平均相对误差为10．0％。     

流动法测定固体在超临界二氧化碳中的溶解度

建立了一套流动法测定固体物质在超临界CO2 中溶解度的实验装置。该装置用高压六通阀取样 ,特别适用于测量溶解度较小的固体物质。以萘为溶质 ,在 32 8K时对装置进行了验证 ,实验结果与文献值基本相符。装置的工作温度 0～ 80℃ ,工作压力 0 .1～ 40MPa。     

Solubility of Disperse Red 82 and modified Disperse Yellow 119 in supercritical carbon dioxide or nitrous oxide with ethanol as a cosolvent

Ethanol was used as a cosolvent to enhance the solubility of disperse dyestuffs in supercritical fluids. In the presence of ethanol, from (1 to 5) mol%, the gas–solid equilibrium data of the Disperse Red 82 and modified Disperse Yellow 119 in supercritical carbon dioxide or nitrous oxide have been measured at temperatures from (353.2 to 393.2) K and pressures from (15.0 to 30.0) MPa. The experimental results show that the solubility increases substantially, up to (9 to 25)-fold, by adding 5 mol% of ethanol to the supercritical fluids. In the presence of cosolvent ethanol, the solubility enhancements in nitrous oxide system are much greater than that in carbon dioxide system for modified Disperse Yellow 119 at the same temperature and pressure. The solubility data were correlated with the Chrastil and the Méndez-Santiago and Teja models. The Méndez-Santiago and Teja model yields slightly better results than Chrastil model.     

川芎油在超临界二氧化碳中溶解度的测定与关联

Extraction of the Ligusticum Chuanxiong oil with supercritical CO2 （SC-CO2） was investigated at the temperatures ranging from 55℃ to 70℃ and pressure from 25 MPa to 35 MPa. The mass of Ligusticum Chuanxiong oil extracted increased with pressure at constant temperature. The initial slope of the extraction was considered as the solubility of oil in SC-CO2. Chrastil equation was used to correlate the solubility data of Ligusticum Chuanxiong oil. An improved Chrastil equation was also presented and was employed to correlate the solubility data, The correlation results show that the values of the average absolute relative deviation are 5.94% and 3.33% respectively, indicating the improved version has better correlation accuracy than that of Chrastil equation.     

分散红73和分散蓝183及其混合物在超临界二氧化碳中溶解度的测定与关联(英文)

The solubility of disperse dyes and their mixture in supercritical carbon dioxide is an important property in study and development of supercritical fluid dyeing technology. In this study, solubilities of C.I. Disperse Red 73, C.I. Disperse Blue 183 and their mixture in supercritical CO2 are measured at temperatures from 343.2 to 383.2 K and pressures from 12 to 28 MPa with a static recirculation method. Under the experimental conditions for the binary (C.I. Disperse Red 73 + CO2 or C.I. Disperse Blue 183 + CO2) and ternary (C.I. Disperse Red 73 + C.I. Disperse Blue 183 + CO2) systems, the solubilities increase with pressure. The solubility of C.I. Disperse Blue 183 decreases with the increase of temperature when the pressure is lower than 16 MPa, and the trend is opposite when the pressure is higher than 16 MPa. However, there is no crossover pressure for C.I. Disperse Red 73. The solubilities are also affected by molecular polarity of dyes. The co-solvent effect exhibited in the dissolving process of mixed dyes promotes their disso-lution in supercritical CO2. The experimental data of solubilities of C.I. Disperse Red 73, C.I. Disperse Blue 183, and their mixture are correlated with the Chrastil model and Mendez-Santiago/Teja model. The former is more accurate.     

Relationship between the solubility of disperse dyes and the equilibrium dye adsorption in supercritical fluid dyeing

In order to understand the dyeing behaviour of synthetic fibres in supercritical carbon dioxide, the solubility of some disperse dyes in supercritical fluid, as well as the rate of dyeing and the equilibrium adsorption of these dyes, have been studied. Dye solubility was measured by a dynamic analytic method at a range of pressure (7.5–25 MPa) and temperature (50–145 °C). The apparent rate of dyeing was measured and the dyeing isotherm was obtained by plotting the equilibrium dye adsorption against the equilibrium dyebath concentration. Linear isotherms were obtained when poly(ethylene terephthalate) samples were dyed with the disperse dyes. The mechanism of dyeing using supercritical carbon dioxide was discussed by considering the solubility, the dyeing rate and the dyeing isotherm.     

苯乙烯在超临界CO2中的溶解度

测定了温度为 32 3.15、 32 8.15、 333.15K ,压力为 3.0～ 2 4 .0MPa条件下苯乙烯 (ST)在超临界二氧化碳 (SC -CO₂ )中的溶解度 ,并根据溶剂化缔合概念、相平衡规则及高压对缔合平衡移动的影响导出溶解度数学模型 .本模型的ST溶解度预测值与实验值吻合良好 .用文献发表的溶解度数据对模型的适用性进行验算 ,也获得了较为满意的结果     

Lipase-catalyzed esterification of stearic acid with ethanol, and hydrolysis of ethyl stearate, near the critical point in supercritical carbon dioxide

The effect of pressure on the lipase-catalyzed reaction in supercritical carbon dioxide (SCCO₂) was investigated for the esterification of steric acid (SA) with ethanol and the hydrolysis of ethyl stearate (ES) near the critical point, ranging from 6 to 20 MPa in pressure and 35 to 60°C in temperature. The esterification rate of SA began to increase near the critical point and kept increasing steadily with an increase in pressure, reflecting the increase in SA solubility in SCCO₂. The hydrolysis rate of ES showed a maximum at a pressure near the critical point. When the reaction was carried out with an initial overall ES concentration below its solubility limit in SCCO₂, the maximum pressure shifted along the extended line of the gas-liquid equilibrium in the supercritical region in the pressure-temperature phase plane. This seems to be related to the singular behavior of some properties in SCCO₂ along this line reported in the literature. These results show the importance of pressure, as well as temperature, as a parameter to control enzyme reactions in SCCO₂.     

苯甲酸在含不同夹带剂的超临界CO2中的溶解度

利用流动法分别测定了苯甲酸在温度308.15, 318.15, 328.15 K、压力范围8.0~23.0 MPa时,在纯超临界CO2及以乙醇、乙酸乙酯、乙二醇为夹带剂的超临界CO2中的溶解度. 研究结果表明,三种夹带剂的加入均可以不同程度地提高苯甲酸的溶解度,其增大幅度为乙醇>乙二醇>乙酸乙酯. 此外还探讨了温度、压力对苯甲酸在超临界CO2中溶解度的影响,以及夹带剂的作用机理,并用Sovova方程对实验数据进行回归,得到了较满意的结果.     

胡椒碱在超临界和近临界二氧化碳中的溶解度

Piperine is a member of the lipids family commonly found in peppercorn, ginger and other natural sources and is grouped as an alkaloid. The solubility of piperine has been determined in carbon dioxide at near critical and supercritical conditions in a dynamic extraction apparatus. The conditions studied were at pressures ranging from 10 to 20 MPa and temperatures at 293, 300, 313, 323 and 333 K. The results showed that piperine solubility increased with increasing pressure at all temperatures studied. The solubility of piperine in near critical conditions was slightly higher than that at supercritical conditions only at the low-pressure range. Two semi-empirical density dependent correlations, namely the Chrastil model and the Dilute Solution model, were also used to estimate the solubility data. Although both models showed good correlation with the solubility data, the Dilute Solution model performed better prediction than the Chrastil model.     

超临界水中硫酸钠溶解度研究

研究硫酸钠在超临界水中的溶解度。在实验范围内 (4 0 0 5 0 0℃ ,2 2 .5 30MPa)测得溶解度均小于40× 10 -6g/g。随温度降低和压力升高 ,硫酸钠溶解度增大。关联了溶解度模型 ,表明同一温度下的硫酸钠溶解度对数与水密度对数呈线性关系。