共查询到17条相似文献,搜索用时 109 毫秒
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利用带有视窗的相平衡装置对共轭亚油酸乙酯在超临界CO2中的溶解度进行了测定。并通过对相平衡釜内体系相态变化的观测,进一步研究超临界相行为。采用Chrastil经验方程对共轭亚油酸乙酯在超临界CO2中的溶解度进行模拟。共轭亚油酸乙酯体系计算值与实验值平均误差为2.43%。 相似文献
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超临界流体萃取中的相平衡进展 总被引:8,自引:0,他引:8
朱自强 《高校化学工程学报》1994,8(1):1-10
概述了超临界流体萃取的发展历史。系统地阐明了超临流体-固体系统相平衡的三种关联方法,对其关联精度进行了比较。介绍了超临界流体-低挥发性液体系统相平衡计算中已看到的状态方程和混合规则。论述了超临界流体-低分子量有机化合物-水系统的相平衡研究进展,对这类系统的超临界流体萃取过程的实质进行了探讨。 相似文献
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超临界状态下的CO2在含有有机溶剂的水溶液中可作为萃取剂。这种情况可用于水和有机酸的分离,也可以用于从水溶液中萃取产品。要设计这样的过程,CO2-H2O-有机酸系统相平衡的数据是必不可少的。为此,在实验室建立了一套高压相平衡装置。为了验证这套装置的可靠性,测定了CO2-H2O-HAc体系在313K以及压力在15、20、25和30MPa下的相平衡数据,用Peng-Robinson方程^[1,2]进行了计算,并与文献值进行了比较。 相似文献
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超临界烯烃配位聚合技术是近年来国际聚烯烃工业领域中的重要进展之一,超临界体系相平衡计算则是该聚合工艺设计与优化操作的基础。本文以链扰动统计缔合流体理论(PC-SAFT)状态方程描述工业级超临界乙烯配位聚合体系的相平衡,得到了适用于该复杂体系的PC-SAFT二元交互参数。与公开报道的实验数据比较表明,获得的二元交互参数可准确描述该超临界体系在较宽温度、压力范围的相平衡。基于上述二元交互参数,针对2个不同双峰聚乙烯产品牌号,计算了工业装置内多组分的相平衡状态,结果表明,反应器内的[H2]/[C2H4]摩尔比、淤浆密度的计算值与工业数据吻合较好,验证了二元交互参数的适用性。研究结果为进一步的工艺流程模拟与优化奠定了基础。 相似文献
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Mohammad Reza Housaindokht Behzad Haghighi Mohammad Reza Bozorgmehr 《Korean Journal of Chemical Engineering》2007,24(1):102-105
Equations of state play an important role in chemical engineering designs, and they have assumed an expanding role in the
study of the phase equilibria of fluids and fluid mixtures. In this report, a modified Peng-Robinson equation of state by
Danesh et al., a modified Peng-Robinson equation of state by Gasem et al., and the Mansoori-Mohsen Nia-Modarress equation
of state are used to predict the solubility of some solids in supercritical carbon dioxide. The systems studied were binary
mixtures containing supercritical carbon dioxide with Ascorbic acid, Ascorbyl palmitate, Butyl hydroxyl anisole, Dodecyl gallate
and Propyl gallate. Interaction parameters for the studied systems are obtained and the percentage of average absolute relative
deviation (%AARD) in each calculation is displayed. 相似文献
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《分离科学与技术》2012,47(13-15):1993-2006
Abstract The separation of alkanes and aromatics with supercritical carbon dioxide has been studied by measuring vapour-liquid equilibria and selectivities in the model systems 2-methylnaphthalene/hexadecane/ carbon dioxide and 2-methylnaphthalene/dodecane/carbon dioxide. The results have been modelled with the Peng-Robinson equation of state. In both model systems supercritical carbon dioxide appeared selective for the component with the highest vapour pressure, 2-methylnaphthalene respectively dodecane. Consequently alkanes and aromatics will be separated by supercritical carbon dioxide on basis of their difference in vapour pressure instead of their difference in chemical structure. 相似文献
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Soon-Do Yoon Yoon-Seok Jang Tae-Hyun Choi Hun-Soo Byun 《Korean Journal of Chemical Engineering》2012,29(3):413-419
Pressure-composition isotherm is obtained for the carbon dioxide+2,2,3,3,3-pentafluoropropyl methacrylate (PFPMA) using static
apparatus with a variable volume view cell at temperature range from 40 °C to 120 °C and pressure up to 130 bar. This system
exhibits type-I phase behavior with a continuous mixture-critical curve. The experimental result for carbon dioxide+PFPMA
mixture was modeled using the Peng-Robinson (P-R) and multi-fluid nonrandom lattice fluid (MF-NLF) equation of state. Experimental
cloud-point data of pressure up 470 bar and temperature to 182 °C were reported for the binary mixture of poly(2,2,3,3,3-pentafluoropropyl
methacrylate) [Poly(PFPMA)] in supercritical carbon dioxide and dimethyl ether (DME). The Poly(PFPMA)+carbon dioxide and Poly(PFPMA)+DME
systems showed LCST behavior. 相似文献
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Solubility of α -asarone in supercritical carbon dioxide was measured and calculated by P-R equation and Chrastil method. Compared with experimental data, the average relative deviation of the calculated solubility of α -asarone is 25% and 8% for P-R equation and Chrastil method respectively,which indicates that the experimental results can be correlated well with Chrastil method.The Chrastil equation for the solubility of α -asarone in supercritical carbon dioxide was subsequently given, which can be applied to the prediction of solubility according to the practical supercritical conditions. 相似文献
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J. Moncada C. A. Cardona Yu. A. Pisarenko 《Theoretical Foundations of Chemical Engineering》2013,47(4):381-387
The solubility prediction of any compound in supercritical carbon dioxide is obtained using the dense gas formulation to calculate the phase equilibria. To achieve this, the Peng-Robinson equation of state with the Stryjek-Vera modification is used. Then, this is coupled with the Wong-Sandler and Van der Waals mixing rules. The latter was included in order to evaluate the influence of the mixing rules in the calculation of the solubility. Therefore, the obtained results from the model are compared with experimental data reported in literature for ferulic acid, p-coumaric acid and caffeic acid contained in citrus seeds. Good agreement was obtained between the model and the experimental data for the phenolic acids, when the Wong-Sandler mixing rules are used. Also the influence of the multicomponent mixture is considered for the prediction of the solubility of phenolic acids in supercritical carbon dioxide. 相似文献
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用静态法测定了高压下CO_2-i-C_3H_7OH二元系和CO_2-i-C_3H_7OH-H_2O三元系的相平衡数据.实验证明超临CO_2能从水溶液中萃取分离异丙醇,并打破了常压下异丙醇-水的恒沸组成.用SRK方程和Huran-Vidal混合规则,建立了CO_2-i-C_3H_7OH-H_2O三元系的热力学模型.此模型只用二元作用系数,能成功地预测三元气液平衡和平衡系线随温度压力剧烈变化的行为.最后,通过实验数据分析和模型预测,探讨了影响超临CO_2从水溶液中萃取分离异丙醇的各种条件. 相似文献