新型改性氧化铝膜蒸汽渗透分离醇水混合物

引言工业生产中经常会遇到醇水混合物的分离问题．膜分离技术与传统的分离过程相比,具有设备简单、操作容易、能耗低和无污染等优点,因此,用经济的膜技术进行醇水混合物分离和浓缩的研究具有广阔的应用前景．其中,采用气相进料的蒸汽渗透膜技术在有机溶剂-水混合物的分离方面显示出明显的竞争优势［1-3］．已报道的用于醇水混合物分离的膜以有机聚合物膜居多．有机膜虽然选择性较高,但其渗透通量却难以满足实际生产的需要．无机陶瓷膜通量大,其选择性则取决于膜孔的大小与结构．为了提高陶瓷膜的选择性,涌现出许多减小膜孔径和改善膜…     

纤维素酯膜的有机物渗透性

本文研究了经丙酮水溶液改性处理后的醋酸纤维素（CA）反渗透（RO）膜的有机物渗透性，在丙酮改性处理过程，透过CA－RO膜的丙酮溶剂量，开始时迅速下降，然后逐渐趋于零，多孔膜变成了致密均相膜，非对称性的超滤（UF）膜，纳滤（NF）膜，RO膜，分别经丙酮改性处理后，甲苯透过膜的渗透速率依次减少。孔径越小，脱盐率越低的RO膜，经改性处理后，甲苯渗透速率越小，三醋酸纤维素（CTA）与醋酸丁酸纤维素（CAB）二组分混的CTACAB膜，或者与醋酸丙酸纤维素（CAP）三组分共混的CTACABCAP膜，随着实验时间的延长，甲苯的渗透速率，前者逐渐下降到接近零时趋于稳定，后者没有变化，改性的CA膜和CTACAB共混膜分离甲基叔丁基醚（MTBE）／甲醇（MeOH)混合物时，渗透能量分别为835和226（g/m^2.h)，渗透物中MeOH浓度都达到88wt％。     

渗透汽化膜组件在有机物-水体系中的应用

介绍了渗透汽化(PV)技术中采用的膜组件的种类及开发现状,论述了近年来渗透汽化膜组件在有机物脱水、水中有机物回收及水中挥发性物质脱除方面的应用状况,探讨了渗透汽化膜组件研究中存在的问题,指出了其未来发展的方向.认为开发新型的膜组件,降低使用膜组件的费用以及开发具有高选择性且稳定性好的PV膜是未来研究的重点;应深入研究膜及膜组件的传质动力学,取得关于膜性能、膜组件构形和过程设计等方面的信息;并将PV膜组件和其他工业过程整合成为一个高效的体系.     

渗透汽化膜分离乙醇水混合物

以自制的壳聚糖／聚丙烯腈透水复合膜，对乙醇水实行渗透汽化分离，分离因子可达１４０～２５００，含水８．９％～３４．６％（质）的溶液，透过液中含水高达９３％～９９．８％（质），渗透总通量为０．１５～１．２５ｋｇ／ｍ￣２·ｈ。     

分离有机/有机混合物的PVA、CA系列膜及其渗透汽化性能研究(Ⅰ)膜材料与成膜工艺

依据溶度参数原则和分离甲基叔丁基醚(MTBE)/甲醇(MeOH)混合物的选择渗透性,选择了聚乙烯醇(PVA)为复合膜的分离层材料,聚丙烯腈(PAN)、醋酸纤维素(CA)系列为支撑层的膜材料.初步讨论了膜材料和复合膜结构对分离性能的影响,给出了用不同成膜工艺制备的膜性能,获得了可用于有机/有机体系分离的性能优良的PVA/PAN和PVA/CA复合膜,以及CTA中空纤维渗透汽化膜.     

分离共沸混合物

在传统的精馏方法达到极限的场合,渗透汽化膜技术将取而代之,膜分离技术使有机溶剂中分离水,甲醇和乙醇变得非常容易。     

分离有机物水溶液的渗透汽化与汽化渗透膜

该文基于４５篇最新文献，较详细地论述了渗透汽化膜与汽化渗透膜的有机物水溶液分离性能及其影响因素，包括高聚物特征，料液浓度，温度，古游侧压力，膜厚度和操作时间，指出用多数高聚物膜进行渗透汽化操作可以有效地分离多数有机醇，酮，酸，酯，酰胺以及二Ｅ烷，乙腈，吡啶，二甲亚砜和四氢呋喃水溶液；而以壳聚糖及其衍生物膜进行汽化渗透操作则具有更高的分离系数。该文还简要介绍了渗透汽化膜的新应用。为渗透汽化与汽化渗透     

有机混合物渗透汽化分离膜材料及成膜技术的研究进展

本文综述了近年来国内外有机溶剂混合物渗透汽化分离膜材料及成膜技术的最新研究进展。指出了制备超薄而致密的复合型渗透汽化膜是提高膜性能的重要途径。     

渗透汽化分离DMF/水混合物的PVA-g-AAm膜的制备和表征

使用聚乙烯醇及丙烯酰胺这两种材料,合成了不同枝度的共聚物(PVA-g-AAm),并对两种渗透汽化复合膜(PVA-g-AAm)进行制备。黏均分子量是运用用黏度法测定的,而表征则分别由接触角,红外光谱(FT-IR)和热重(TGA)等方法进行测定。而DMF/水混合体系的渗透汽化分离主要是复合膜的运用,并对膜分离的影响因素进行分析。实验结果显示,分离性能最好的是接枝度为90%的PVA。而PVA的渗透量随着DMF质量分数的增加而减少,PVA的通量最小时是在0.25~0.65 kg/(m~2·h)之间,在0.2~而膜的分离因子达到最大时DMF质量分数为33%。而温度的增加可是渗透量增大,分离因子减小。     

芳烃/脂肪烃混合物分离渗透汽化膜的研究进展

芳烃/脂肪烃混合物的分离是化学工业中的重要过程,但是由于其物理和化学性质非常相似,采用传统方法分离困难。与传统的分离技术(萃取、蒸馏)相比,渗透汽化技术在经济、节能和环保方面具有很大的发展前景。本文综述了用于芳烃/脂肪烃混合物渗透汽化分离的渗透汽化膜的研究进展,对渗透汽化技术用于芳烃/脂肪烃混合物的研究前景进行了展望。     

SEPARATION OF OIL-WATER MIXTURE IN TANK

Experimental investigations have been carried out to separate diesel oil-water mixture in unbaffled, baffled (with different inclination of baffle), and variable area baffled separators. A baffle separator with a 45° inclination to vertical has been found to be most suitable for the oil-water separation.     

DRYING KINETICS OF A MULTICOMPONENT MIXTURE OF ORGANIC SOLVENTS

Drying kinetics of volatile organic solvents have been examined during the drying process of a pharmaceutical coating containing a multicomponent mixture of ethyl acetate, n-heptane, propanol-2, and toluene. A complete set of experiments was performed in two drying apparatuses, a laboratory air-dryer and an oven dryer, for a wide range of drying temperature, air velocity, initial coating thickness and drying time. An empirical kinetic model is used to predict the concentration of each organic solvent in the mixture during the drying process. The results show that both drying conditions and sample characteristics affect significantly the drying rate of solvents.     

THE SEPARATION OF ACETONE-METHANOL MIXTURE BY EXTRACTIVE DISTILLATION

Acetone and methanol can not be readily separated by ordinary distillation because of the presence of the minimum boiling azeotrope. Either acetone or methanol can be the overhead product when an appropriate agent is applied in extractive distillation. An unusual phenomenon, “temperature inversion”, was observed when ketones were used as the extractive distillation agents. The dissolving of the vapors into the liquid phase could be the cause for the overhead at a temperature higher than that of the stillpot.     

DRYING KINETICS OF A MULTICOMPONENT MIXTURE OF ORGANIC SOLVENTS

ABSTRACT

Drying kinetics of volatile organic solvents have been examined during the drying process of a pharmaceutical coating containing a multicomponent mixture of ethyl acetate, n-heptane, propanol-2, and toluene. A complete set of experiments was performed in two drying apparatuses, a laboratory air-dryer and an oven dryer, for a wide range of drying temperature, air velocity, initial coating thickness and drying time. An empirical kinetic model is used to predict the concentration of each organic solvent in the mixture during the drying process. The results show that both drying conditions and sample characteristics affect significantly the drying rate of solvents.     

中空纤维He-CH_4膜分离器分离性能的研究

以He-CH_4二元混合气体为被分离体系,对由中空纤维型醋酸纤维膜与毛细管型硅橡胶膜构成的单膜分离器和由此构成的连续式双膜分离塔进行了实验研究;探讨了有关参数及流型对分离器分离性能的影响;测试、关联及分析了渗透系数和分离因子随气体操作条件改变的变化规律;用作者建立的理论模型对所有的实验点进行了验证。     

渗透蒸发在有机溶剂混合物分离中的应用

本文综述了近年来渗透蒸发在有机溶剂分离中的研究动向,并就膜结构和操作条件对渗透蒸发性能的影响做了简单的讨论。指出了今后的发展趋势。     

SOLVENT EXTRACTION OF PALLADIUM(II) WITH A SCHIFF BASE AND SEPARATION OF PALLADIUM FROM Pd(II)-Pt(VI) MIXTURE

ABSTRACT

A new Schiff base extractant, N,N'-bis[l-phenyl-3-methyl-5-hydroxy-pyrazole-4-benzylidenyl]-l,3-propylene diamine (H₂A) was synthesized and characterized. The extraction mechanism of palladium(II) from HNO₃ or HClO₄ medium with H₂A in chloroform or toluene was investigated. The influences of the Schiff base concentration in the organic phase, the concentration of palladium, the pH and anions (Cl^?, S0₄ ^?, NO₃ ^?, ClO₄ ^?) in the aqueous phase and the temperature on the distribution ratio for palladium (II) have been examined. The extracted complex has been confirmed by chemical analysis, thermoanalyses and IR spectroscopy. It was found that palladium is extracted according to the following extraction reaction:

The extraction equilibrium constants of palladium(II) were 8·4 and 21·3 in chloroform and toluene diluents, respectively. The values for the enthalpy and standard free energy of extraction were also obtained. The separation of Pd(II) from the mixed solution of Pd(II)-Pt(IV) was achieved by adjusting the pH.     

有机溴杀菌剂工业应用效果与评价

通过工业应用试验,表明有机溴杀菌速度快,对粘泥有较好的剥离效果,和水稳剂有良好的协同效应,费用低,投加方便,加氯的同时定投加有机溴是碱性条件下一种有效的杀生方案。     

膜法处理高浓度氨氮废水的研究

采用电渗析法和聚丙烯(PP)中空纤维膜法处理高浓度氨氮无机废水可取得良好的效果。电渗析法处理氨氮废水，浓度2000～3000mg／L，氨氮去除率可在85％以上，同时可获得8．9％的浓氨水。此法工艺流程简单、投资省、不消耗药剂、运行过程中消耗的电量与废水中氨氮浓度成正比。PP中空纤维膜法脱氨效率≥90％，回收的硫酸铵浓度在25％左右。此法工艺流程短、技术先进、省电，无二次污染，运行中需加碱，加碱量与废水中氨氮浓度成正比。     

WATER SOLUBILITY OF SOLID SOLUTION OF PHENANTHRENE AND ANTHRACENE MIXTURE

Water solubilities of solid solution forms of phenanthrene and anthracene in water between 283 K and 308 K were measured by the shake flask method. The present experimental results showed that solid composition affected the water solubility of the solid solution as follows: The saturation concentration of a solute decreased with an increase in the amount of the other in the solid phase. In particular, this solubility decrement was remarkable within a low concentration range of anthracene in the solid solution. Within the same range, furthermore, the temperature dependence of the anthracene water solubility increased while that of phenathrene decreased. Finally, we tried to calculate the solubility behavior, based on the fugacity ratio between the liquid and solid phases and an activity coefficient model.