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超临界流体色谱法测定固体在二氧化碳中的溶解度 总被引:2,自引:0,他引:2
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。 相似文献
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Aziz I. Abdulagatov Genadii V. Stepanov Ilmutdin M. Abdulagatov Asbat E. Ramazanova Genrietta S. Alisultanova 《Chemical Engineering Communications》2003,190(11):1499-1520
The experimental and predicted loci extrema behavior of the isochoric heat capacity C V was examined for water and carbon dioxide along the subcritical and supercritical isotherms and along the liquid and vapor isochores. The studies were based on a nonanalytical Helmholtz energy-volume-temperature equation ( AVT , fundamental equation of state), the IAPWS-95 formulation for water, and scaling-type crossover equations of state (CREOS). The measured isochoric heat capacity data for these fluids near the critical point were analyzed to study the behavior of loci of C V maxima and to compare these with predictions by the equations of state. A CREOS was applied to study the behavior of the isochoric heat capacity maxima in the immediate vicinity of the critical point. Good agreement with the CREOS prediction and experimental isothermal C V maxima loci was observed near the critical point. The basic characteristic points on the C V extrema loci curves in the P - T and ρ- T planes were determined on the basis of detailed analysis of the experimental and prediction of C V extrema loci behavior. Qualitative explanations are given for the nature of isochoric and isothermal C V maxima-minima curves. The role of C V extrema loci behavior in developing high-accuracy equations of state in the supercritical region and in the study of supercritical phase-transition phenomena are discussed. 相似文献
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Yukihiko Matsumura Masaki Harada Kyoko Nagata Yoshihiro Kikuchi 《Chemical Engineering Communications》2006,193(5):649-659
The effect of feedstock heating rate on the efficiency of gasification of a biomass in supercritical water was investigated using a continuous bench-scale reactor. A glucose solution (biomass model compound) and a cabbage slurry were gasified in supercritical water at various heating rates in a preheater. The results show that in the range of 10-30 K/s, carbon gasification efficiency improved as the heating rate increased. 相似文献
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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。 相似文献
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The solubility of styrene from polystyrene in supercritical carbon dioxide is measuredat 323 K,333 K,and 343 K in the pressure range from 12 to 28 MPa.Based on the associationconcept and the theory of dense gas sorption in polymers,a displacement and association mechanismon supercritical fluid extraction of the monomer from the polymer is proposed.And,a novel math-ematical model for correlating the solubility data obtained from the experiments is also proposed inthe paper. 相似文献
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超临界流体萃取沙棘油实验研究 总被引:11,自引:0,他引:11
建立了一套萃取实验装置 ,对超临界CO2 流体萃取沙棘油进行了实验研究。压力 15— 30MPa,温度 30— 5 0℃。分别考察了萃取压力、萃取温度、颗粒度、物料填充量以及萃取时间等条件对萃取率的影响 ,并就工艺参数对萃取率的影响机理和原因进行了分析与讨论。结果表明 :当压力为 2 5MPa、温度为 40℃时可获得较高的萃取率。流量为 0 .2m3 /h时 ,萃取时间为 4— 5h。化学成分分析结果证明 :沙棘油中饱和脂肪酸含量占 12 .3%,不饱和脂肪酸含量占 87.7%。 相似文献
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根据Koningsveld等人推广的Flory-Huggins关于高聚物溶液理论,提出了用聚乙烯-丙烷体系标样的超临界流体相平衡浊点线实验值来模拟计算临界点的方法.结果表明,该计算方法简便,计算结果与实验数据基本相符. 相似文献
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引 言纤维素含量约占 50 %的生物质资源 ,是非常有应用前景的可再生资源 .目前用于大规模处理生物质资源的方法有酸水解、热分解和水蒸气蒸爆等 .酸水解的目标是最大限度地获得单糖 ,它又可发为浓酸水角[1] 与稀酸水解[2 ] .酸水解具有以下缺点 :①反应速度较慢 (最大 0 .1min- 1) ;②反应器腐蚀严重 ;③需国收酸 (浓酸水解 )以及废水处理等 .热分解的目标是生成燃料 ,Antal等[3] 对此进行大量的研究 ,此法设备与工艺均较简单 ,但存在着产品价值较低、污染严重等问题 .水蒸气蒸爆因水解率低 ,一般只作为预处理技术[4 ] .另外还有人… 相似文献
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为了满足超临界CO2回收溶剂法提取油砂沥青的提取溶剂重整汽油的工艺需要,采用可变体积高压相平衡装置,在温度为30.3~70.2℃下,测定了4.02~14.01MPa范围内CO2-重整汽油拟二元体系的气液两相的平衡组成、密度以及摩尔体积。通过得到的结果确定了利用超临界二氧化碳来回收重整汽油的操作条件范围。利用基团贡献法估算了重整汽油的特性参数。采用Peng-Robinson方程拟合回归实验数据,得到了CO2-重整汽油体系的交互参数,计算出CO2-重整汽油体系的相平衡数据,结果表明计算值与实验值吻合较好。 相似文献