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.     

夹带剂性质对超临界二氧化碳萃取的影响

介绍了夹带剂在超临界CO2萃取中的作用和原理，分析了夹带剂分子极性、相对分子质量、分子体积及特殊分子结构等性质对超临界CO2萃取的影响，总结出夹带剂性质对萃取率的变化规律：夹带剂的分子极性越大，溶质在超临界CO2中的溶解度越大；夹带剂的相对分子质量、分子体积的增大，其在超临界CO2中的溶解度减小，萃取率减小；夹带剂中易形成氢键的特殊分子结构，可提高萃取率。     

α-萘乙酸与β-萘酚在含夹带剂超临界CO2中溶解度的研究

采用流动法，以乙醇、丙酮、环己烷为夹带剂，测定了固体溶质α-萘乙酸在超临界CO2中的溶解度，并与相应的β-萘酚的溶解度进行了对比研究。试验结果表明，溶质溶解度随压力的升高而增大；高压下高温萃取有利，低压下低温萃取有利；无论何种夹带剂的加入，均能在一定程度上增加溶质的溶解度，但对于极性溶质，极性夹带剂对其溶解度的提高作用更加显著。     

2-萘酚与苯甲酸在含夹带剂的超临界流体中溶解度的研究

在自建的超临界流体溶解度实验装置中，测定了固体溶质2—萘酚、苯甲酸在超临界CO2中的溶解度，实验对该类物质的超临界萃取提供了基础数据。对数据的分析讨论表明，随着压力的升高，物质的溶解度增高；随着温度的升高，溶解度的变化比较复杂，在低于特定压力(转变压力)时，温度升高，溶解度增高；在高于特定压力时，温度升高，溶解度降低；夹带剂可以大大提高固体溶质的溶解度，不同的夹带剂，所起作用大小不同；夹带剂的极性、氢键作用对溶解度的提高起着很重要的作用。     

对羟基苯甲酸甲酯在含夹带剂超临界CO2中溶解度的研究

采用流动法测定了对羟基苯甲酸甲酯在含和不舍夹带剂的超临界CO2中的溶解度,实验所用夹带剂分别为正己烷、乙醇、丙酮及混合夹带剂正己烷 丙酮(摩尔比为1：1),夹带剂的摩尔分数均为0．035。论述了温度、压力和夹带剂对固体溶解度的影响,然后用化学缔合模型关联了实验数据,实验值与计算值吻合良好。     

苯甲酸在含夹带剂的超临界CO2中溶解度的研究

采用流动法研究和测定了苯甲酸在35、50℃下,10.0—30.0MPa范围内,在纯超临界CO2和含醇系列夹带剂的超临界CO2中的溶解度。实验研究表明,醇系列夹带剂的加入均可明显增大苯甲酸的溶解度,但4种醇的增强作用随着碳链的增加而略有减弱。论述了温度、压力对溶解度的影响,并用Sovova方程对实验数据进行了回归。     

关于超临界萃取过程中使用夹带剂的研究

建立了一套研究夹带剂的超临界萃取装置。在胡罗卜素及罗汉果糠甙的萃取中,分别使用丙酮和乙醇做夹带剂,研究它们对溶解度、收率及选择性的影响。     

夹带剂性质对超临界二氧化碳萃取的影响

系统地论述了夹带剂在超临界CO2萃取中的作用和原理，分析了夹带剂性质对超临界CO2萃取的影响，提出了夹带剂选择的一般步骤及其所要注意的问题，为超临界CO2萃取中夹带剂的选择提供了一定的理论依据。     

红外光谱测量法研究超临界CO2中夹带剂与溶质的相互作用

利用红外光谱技术研究了在超临界CO₂中加入不同夹带剂时，水杨酸中基团的伸缩振动频率的位移及夹带剂与溶质的相互作用。以乙醇为夹带剂时，水杨酸中C=O基团、O—H基团的伸缩振动频率均向低频方向移动;以丙酮为夹带剂时，水杨酸中C=O基团伸缩振动频率向高频方向移动。研究结果表明：当以乙醇为夹带剂时，水杨酸的溶解度远大于以丙酮为夹带剂时的结果，夹带剂对溶质增溶的作用能力，形成氢键的作用远大于溶剂极性的作用。     

固体溶质在含夹带剂超临界流体中的溶解度(Ⅱ)——准液体模型

推导和建立了计算固体溶质在含夹带剂超临界流体中溶解度的准液体模型。结果表明,理论计算值与文献数据和本文实验数据均有较好的吻合。     

EPA-乙酯和DHA-乙酯在超临界二氧化碳中色谱容量因子与溶解度的关系

以二氧化碳为流动相，ODS柱为固定相，测定了二十碳五烯酸乙酯（EPA－EE）和二十二碳六烯酸乙酯（DHA－EE）的超临界流体色谱容量因子。从宏观热力学出发，研究了溶质的超临界流体色谱容量因子及其在超临界二氧化碳中溶解度的关系，并用实验数据对该热力学关系作了验证。     

Analysis of cosolvent effect on supercritical carbon dioxide extraction for α-pinene and 1,8-cineole

The solubilities of α-pinene and 1,8-cineole in supercritical carbon dioxide with and without cosolvent were measured by using a circulation type apparatus coupled with an on-line Fourier transform infrared (FT-IR) spectroscope at 323 K and 8.0 MPa. The cosolvents interested in this work were ethanol, water, acetone and hexane. The solubilities were measured under vapor–liquid two phases. The effects of cosolvents on the solubilities and selectivities of α-pinene and 1,8-cineole in supercritical CO₂ were investigated. The selectivities at feed concentration of cosolvent of 0.056 mol L⁻¹ were increased 1.23 times by ethanol and decreased 0.82 times by hexane. Peng–Robinson equation of state with a quadratic mixing rule was used for correlations of the solubilities for α-pinene and 1,8-cineole in supercritical CO₂ with and without cosolvent. The correlated results reproduce the experimental data of cosolvent effects on the solubilities and selectivities of α-pinene and 1,8-cineole in supercritical CO₂.     

邻羟基苯甲酸和邻甲氧基苯甲酸在超临界CO2中的溶解度研究

采用流动法测定和研究了邻羟基苯甲酸和邻甲氧基苯甲酸在308K、328K下,10．0～24．0MPa范围内,在纯超临界CO2中的溶解度,并简要分析分子极性和结构特点对固体溶质溶解度大小的影响。同时,将超临界流体视为膨胀液体,根据溶液理论,建立了计算溶质在超临界流体中溶解度的膨胀液体模型。应用该模型对试验数据进行回归,得到了令人满意的结果。     

Solubility of Jatropha and Aquilaria oils in supercritical carbon dioxide at elevated pressures

This study investigated experimental equilibrium solubilities of Jatropha curcas and Aquiliaria crassna oils dissolved in supercritical carbon dioxide at temperatures of 318-338 K and pressures of 20, 25, 30, 35 MPa. The highest solubility of J. curcas and A. crassna oil were 29.8 and 28.4 mg L⁻¹, respectively, at 338 K and 35 MPa. The oil solubilities and the concentration of triglycerides both increased with increasing temperature and pressure. Triglyceride molecules surrounded by carbon dioxide molecules may be proposed since solubilities increased with the flux of supercritical carbon dioxide. The solubility of these two oils linearly increased with the density of supercritical carbon dioxide. Experimental data of the oil solubility were successfully correlated by the Chrastil equation.     

二乙基二硫代氨基甲酸二乙胺在超临界CO_2中的溶解度测定

利用动态法测定了超临界络合萃取中的一种重要络合剂——固体二乙基二硫代氨基甲酸二乙胺(Et2NH2DDC)在超临界CO2中的溶解度。实验的温度、压力范围分别是308.2~328.2K,10.0~30.0MPa;溶解度随着温度、压力的增大而增大。将实验结果用Chrastil缔合模型法进行关联,取得了比较好的关联精度。     

Solubility of fish oil fatty acid ethyl esters in suband supercritical carbon dioxide

Mutual solubilities and K-values of fish oil fatty acid ethyl esters, prepared from sand launce oil, and sub- and supercritical carbon dioxide have been measured in an apparatus originally designed for phase equilibrium, density and gasoil ratio measurements of reservoir fluids. The measurements were performed at pressures from 2 to 22 MPa at temperatures of 283.2, 313.2 and 343.2°K. Experimental temperatures, pressures, solubilities, K-values and densities are reported. The K-values of ethyl myristate, palmitate, oleate, eicosapentaenoate and docosahexaenoate are compared with published experimental binary and/or multicomponent data. Because both vapor and liquid solubilities are reported, such data are applicable in the design of supercritical extraction plants.     

Measurement and correlation for the solid solubility of non-steroidal anti-inflammatory drugs (NSAIDs) in supercritical carbon dioxide

The solubilities for three non-steroidal anti-inflammatory drugs (NSAIDs) of nabumetone, phenylbutazone and salicylamide in supercritical carbon dioxide were measured in this study using a semi-flow type apparatus. The experimental data were taken at 308.2, 318.2 and 328.2 K, over the pressure range from 10 to 22 MPa. The measured results were then correlated using semi-empirical equation presented by Chrastil, and that presented by Mendez-Santiago and Teja. With optimally fitted parameters, these two equations yielded satisfactory results where the average absolute relative deviation (AARD) was below 7%. Furthermore, the solid solubilities of these three compounds and seven other NSAIDs in supercritical carbon dioxide were correlated by applying the regular solution model coupled with a Flory–Huggins term. The solution model, which has fewer parameters than the semi-empirical equations, yielded comparable correlation results. The parameters in the solution model could be generalized for the specific group of NSAIDs. Finally, the predicted solubilities of 10 NSAIDs in supercritical carbon dioxide were demonstrated to be reliable.     

分散红343、分散蓝366及其混合物在超临界CO_2中的溶解度测定和关联

为超临界CO2染色工艺提供必要的基础数据,采用静态循环法在343.2～383.2 K,12～28 Mpa温度压力范围内,测定了分散红343和分散蓝366及其混合物在超临界CO2中的溶解度.实验结果表明,二元体系(分散红343+CO2,分散蓝366+CO2)和三元体系(分散红343+分散蓝366+CO2)中染料的溶解度均随温度和压力的升高而增大;染料分子的极性对其在超临界CO2中的溶解度影响较大;三元体系中两种染料的溶解存在"共溶剂效应"和竞争溶解作用;两种染料在二元和三元体系中的溶解度实验数据用Chrastil方程关联,结果较好.     

Experimental determination and activity coefficient based models for mixture solubilities of nitrophenol isomers in supercritical carbon dioxide

The experimental solubilities of the mixture of nitrophenol (m- and p-) isomers were determined at 308, 318 and 328 K over a pressure range of 10–17.55 MPa. Compared to the binary solubilities, the ternary solubilities of m-nitrophenol increased at 308, 318 and 328 K. The ternary solubilities of p-nitrophenol increased at 308 K, while the ternary solubilities decreased at lower pressures and increased at higher pressure at 318 and 328 K. The solubilities of the solid mixtures in supercritical carbon dioxide (SCCO₂) were correlated with solution models by incorporating the non-idealities using activity coefficient based models. The Wilson and NRTL activity coefficient models were applied to determine the nature of the interactions between the molecules. The equation developed by using the NRTL model has three parameters and correlates mixture solubilities of solid solutes in terms of temperature and cosolute composition. The equation derived from the Wilson model contains five parameters and correlates solubilities in terms of temperature, density and cosolute composition. These two new equations developed in this work were used to correlate the solubilities of 25 binary solid mixtures including the current data. The average AARDs of the model equations derived using the NRTL and Wilson models for the solid mixtures were found to be 7% and 4%, respectively.     

苯酚在亚临界及超临界CO_2中溶解度的测定

利用流动法高压相平衡装置,测定了苯酚(固态)在亚临界和超临界CO_2中的溶解度.实验是在303-312K,8.5—50MPa的范围内进行.将实验数据与SRK和PR状态方程进行关联,得到了较好的结果.