共查询到19条相似文献,搜索用时 62 毫秒
1.
本实验通过拟合不同类型乙醇—环己烷质量分数—折射率曲线,利用拟合曲线绘制乙醇—环己烷双液系气—液平衡相图,分析不同类型拟合曲线对绘制平衡相图的影响。结果表明一次方程拟合的工作曲线处理数据简单方便且结果理想,建议学生实验采用一次方程拟合。 相似文献
2.
3.
4.
5.
6.
共沸精馏是非理想体系的多组分分离。各个因素之间的关系比较复杂,给流程方案的设计增加了难度。现行的共沸精馏流程长、能量消耗大。本文应用三角相图分析法改进了流程。 相似文献
7.
8.
9.
对二元液系平衡相图实验在实验体系和装置上进行改进,改进后操作安全、方便、环保,试剂易得、价格与原试剂相差不多,实验效果较好。 相似文献
10.
立方形状态方程的相图分析 总被引:1,自引:0,他引:1
本文通过对修正Ω的R-K方程的数学分析,对根的取舍和判断作了明确的解释。通过对纯二氧化碳、二氧化碳-异丁烷以及二氧化碳-正癸烷体系的P-V相图分析,可以了解各相图区中的VL,Vv以及汽液两相共存区的准确位置和数值,及其可能导致的误差。 相似文献
11.
J. Rouse S. T. Adamy A. Mehreteab G. Broze 《Journal of the American Oil Chemists' Society》1995,72(1):37-42
An automated titration system has been developed for generating data to construct phase diagrams, which are extremely useful
in the development of personal and household products. In this report, we describe the system and how it can be utilized to
perform the technique of dual titration. In the procedure, a clear microemulsion sample is titrated with an oil until the
dispersion turns cloudy (defined to be a transmittance below 90%). The mixture is then dosed with a certain quantity of cosurfactant,
more than enough to clear the mixture. The sample is again titrated with oil. This process continues until the sample no longer
clear upon adding cosurfactant. The resulting measurements of oil uptake can be used to characterize the boundaries of the
L1 or oil-in-water microemulsion region of the phase space. Experiments for up to sixteen samples can be performed, each having
individual setup and operating instructions. Features include completely automated operation, computer-controlled two-speed
mixing, viscosity detection at the end-point condition and the storage of results in a computerized format. 相似文献
12.
13.
Hiroshi Takiyama Takuma MinamisonoYohei Osada Masakuni Matsuoka 《Chemical Engineering Research and Design》2010
In the pharmaceutical production, to control polymorph formation is important from the viewpoint of the productivity and the bioavailability. Anti-solvent or drowning-out crystallization is widely used in the pharmaceutical industry for high yield production. However, anti-solvent addition method to control polymorph formation in anti-solvent crystallization has not been discussed enough. In this study, indomethacin (IMC) which has three polymorphs was used. The purpose of this study is to establish a production method of the target polymorph in the anti-solvent crystallization (IMC–acetone–heptane system). The simulation model for determination of anti-solvent feed rate based on the ternary phase diagram was proposed. The stability of the polymorph of IMC crystal in the solution was changed not only with temperature but also with composition of the mixed solvent. From the experimental and simulation results, the design strategy of anti-solvent crystallization was proposed. 相似文献
14.
The phase transformation between diamond and graphite has been studied by calculating the transiting probability of the carbon atoms over a potential barrier. For the first time, the boundaries of the proposed metastable regions of diamond and graphite have been estimated theoretically, and the currently used characteristic paths of pressure-temperature for synthesizing diamond using a high pressure and high temperature (HPHT) method can be understood. 相似文献
15.
16.
Salt-forming regions for a complex salt-water system in non-equilibrium state of evaporation process are usually different from those in solubility diagrams.To understand the solid-forming region of NaCl and improve the utilization of bittern resources,experiments were carried out to evaporate 20 representative mixture solution samples of Na +,Mg 2+ //Cl-,2 4 SO-H2O system with an average evaporation intensity of(1.4±0.4) g·L-1 ·min-1(water) at boiling temperature 348 K,and determine the NaCl solid-forming regions in non-equilibrium state.Because of the complexity of salt-forming region,a maximal region and a minimal region were proposed to express the non-equilibrium state salt-forming region with different crystal seed,and a conditional salt-forming region was proposed to present the characteristic region of non-equilibrium salt-forming phase diagram.The areas of the maximal and minimal regions are 2.00 and 1.56 times those in solubility diagram,so it is possible to utilize bittern resources in high efficiency.The recovery rates of NaCl were 99.65%,93.14%,88.57%,72.76%,and 83.68%for six typical bittern sources from Tulantai Salt Lake(China),Dongtai Salt Lake(China) ,Jilantai Salt Lake(China),Qarun Salt Lake(Egypt) and seawater,respectively.It is testified that the non-equilibrium state salt-forming phase diagram can be used in industrial processes. 相似文献
17.
Theoretical phase diagram calculation and membrane morphology evaluation for water/solvent/polyethersulfone systems 总被引:1,自引:0,他引:1
Theoretical ternary phase diagrams with very good agreement with experimental cloud point data were constructed for water/N,N-dimethylacetamide (DMAc)/polyethersulfone (PES) and water/N-methyl-2-pyrrolidone (NMP)/polyethersulfone systems. Theoretical phase diagrams were determined based on the extended Flory-Huggins theory of polymer solutions. To construct the theoretical phase diagrams, all binary interaction parameters were determined accurately and thoroughly revisited. Also, the structures of membranes prepared of these systems by phase separation process were investigated. The morphological studies showed that in spite of better miscibility between water and DMAc compared to water and NMP, channel-like structures were observed in membranes prepared of water/NMP/PES systems but tear-like structures with more spongy areas were observed in membranes prepared of water/DMAc/PES system. According to the constructed theoretical ternary phase diagrams of these systems, these unexpected observations were attributed to the higher concentration of polymer in the polymer-rich phase of water/DMAc/PES system, which causes an early vitrification in this system which suppresses the growth of macrovoids. 相似文献
18.
硫酸钙制取硫酸钾相图及实验研究进展 总被引:8,自引:0,他引:8
利用10℃ K^ ,Ca^2 //SO4^2-,Cl^-,NH3-H2O(溶剂中氨的平衡质量浓度为36%)体系的有关溶解度数据,进行了石膏法制取硫酸钾工艺的相图研究及实验研究,得到了一些新的结论,合适牟工艺条件为:配料比为2KCl;CaSO4.2H2O(摩尔比)等于1:1-1.05:1,液固比5.5-5.8,反应时间0.5h,石膏粒度0.2-0.17mm。 相似文献
19.
采用静态法测定了293.15~323.15 K范围内,阿奇霉素二水合物在丙酮-水和异丙醇-水混合溶剂中的溶解度,并研究阿奇霉素在293.15、298.15、303.15及308.15 K温度下丙酮-水混合溶剂中转晶水活度,根据溶解度特性绘制丙酮-阿奇霉素-水三元相图,溶解度数据用Apelblat方程、λh方程和van’t Hoff方程进行关联。结果表明,阿奇霉素溶解度随着有机溶剂体积分数和温度的升高而增加,转晶水活度随温度的升高增大,阿奇霉素一水二水共存区域随温度的升高减小,Apelblat方程拟合效果更好,R2≥0.988。 相似文献