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）、醛酸纤维素（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。     

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。     

芳香聚酰胺类反渗透膜的研究进展

芳香聚酰胺具有酰胺基团(-CO-NH-),亲水性好,且其机械稳定性、热稳定性及水解稳定性均很好,特别适用于反渗透过程.目前,芳香聚酰胺类膜已经成为主导的反渗透膜产品,广泛应用于海水淡化、电厂水处理、纯净水制取等领域.对近10多年来芳香聚酰胺类反渗透膜的制备,改性等方面的研究进行综合评述.     

有机混合物的渗透蒸发分离

有机混合物渗透蒸发分离技术在技术发展很快,膜的种类繁多,和化学性质差别很大,本文首先总结了分离有机混合物渗透蒸发膜的详细分类 及膜对应的分离物系,不同膜的物理性能和分离效果比较,在后对膜的多种改性方法作了较合面的论述。     

二元混合物降膜蒸发的数值模拟

提出了二元混合物在垂直圆管中降膜蒸发的传热传质耦合数学模型及其相应的数值解法 .模型考虑了液膜内传质对传热的影响 .计算表明传质对传热有明显影响 ,忽略传质的影响对预测膜平均传热系数会带来较大误差 .     

二醋酸纤维素和醋酸丁酸纤维素反渗透混合膜的研制

本文主要描述CA-CAB 反渗透混合膜的配方和原料的选择,探讨了聚合物的比率、添加剂浓度、热处理温度和介质等因素对膜性能的影响,采用CA-CAB 的比率为9∶1或8∶2,可以获得脱盐率为90%—93%,产水量为8—12 L/(m~2·h)的CA-CAB反渗透混合膜。     

A TRANSPORT MODEL FOR REVERSE OSMOSIS SEPARATION OF BINARY ORGANIC LIQUID MIXTURES

A set of transport equations was derived for the separation of the binary mixtures of organic solvents on the basis of the surface force-pore flow (SFPF) model. These equations enable the quantitative prediction of the membrane performance data under a given set of operating conditions together with the information on the membrane pore size, interaction forces working between the solution components and the membrane material, and the activity and the molecular radii of solution components. The usefulness of such transport equations is shown for the system ethyl alcohol-heptane-cellulose membrane and some other separation systems.     

表面改性纳米二氧化钛-芳香聚酰胺复合反渗透膜的制备与表征

采用TMC对亲水纳米TiO2进行表面改性,然后添加在复合反渗透膜的聚酰胺层中,制备了改性纳米TiO2-聚酰胺复合反渗透膜。改性纳米TiO2使用红外光谱法(FTIR)和粒径分析仪进行表征;采用渗透试验,扫描电镜(SEM)、静态接触角仪、原子力显微镜等对复合膜的性能和结构分别测试和表征。结果表明,改性TiO2的表面接枝上酰氯基团,在有机溶剂中的分散性得到提高;SEM和AFM照片证实,TiO2在膜表面分布均匀,膜表面粗糙度增加;杂化复合膜亲水性也有一定程度的提高;膜性能测试结果证实了添加TiO2的复合膜水通量均高于纯聚酰胺膜,同时脱盐率变化很小。当改性TiO2的添加量为0.05%(m/v)时,水通量由11.21 L/(m2.h)提升到32.61 L/(m2.h),对NaCl截留率达到98.9%。试验结果表明,改性TiO2很好地分散在聚酰胺层,提高了水通量,还保持了高脱盐率,膜性能得到提高。     

REVERSE OSMOSIS SEPARATION OF GLUCOSE-ETHANOL-WATER SYSTEM BY CELLULOSE ACETATE MEMBRANES

The separation of glucose-ethanol mixed solutes from aqueous solutions was attempted by cellulose acetate membranes of different average pore sizes and pore size distributions at the operating pressure of 6895 kPag (=1000 psig) and at the feed glucose concentration ranging from 2000 to 75000 ppm while maintaining ethanol concentrations at 1/5 to 1/2 of the glucose concentration. Using chosen reference solutes the pore size distribution on the membrane surface was characterized by two normal distributions. It was found that ethanol is attracted to the cellulose acetate membrane material more strongly at the higher glucose concentration in the feed solution, and consequently the separation of ethanol solute is brought down at higher glucose concentrations. These results are attributed to lowering of solubility of ethanol in the solvent when a greater amount of glucose is in the solvent.     

REVERSE OSMOSIS SEPARATION OF GLUCOSE-ETHANOL-WATER SYSTEM BY CELLULOSE ACETATE MEMBRANES

The separation of glucose-ethanol mixed solutes from aqueous solutions was attempted by cellulose acetate membranes of different average pore sizes and pore size distributions at the operating pressure of 6895 kPag (=1000 psig) and at the feed glucose concentration ranging from 2000 to 75000 ppm while maintaining ethanol concentrations at 1/5 to 1/2 of the glucose concentration. Using chosen reference solutes the pore size distribution on the membrane surface was characterized by two normal distributions. It was found that ethanol is attracted to the cellulose acetate membrane material more strongly at the higher glucose concentration in the feed solution, and consequently the separation of ethanol solute is brought down at higher glucose concentrations. These results are attributed to lowering of solubility of ethanol in the solvent when a greater amount of glucose is in the solvent.     

低压醋酸纤维素中空纤维反渗透膜及组件研制

本文报导了以二醋酸纤维素(CA)为原料,通过溶液干湿法多孔纺丝制膜技术生产低压中空纤维反渗透膜及组件的研究成果。研制的TF-100型(4″)RO 组件在以自来水为进水,操作压力1MPa,水回收率50%条件下测试;脱盐率为93%,产水量为200 L/h(25℃)。组件可用于自来水和低度含盐水的脱盐。     

THE FABRICATION AND PERFORMANCE OF CELLULOSE REVERSE OSMOSIS MEMBRANES

A method for the fabrication of reverse osmosis membranes made from cellulose material is reported along with their performance data with respect to the separation of single electrolyte solutes from their aqueous solutions. The separation depends on the charge and the valence of the ions involved as well as the porosity of the membrane. The larger rejection for electrolytes involving negative ions of higher valence is attributed to a net negative charge on the surface of the membrance. Further, it was found that the solute separation decreases with an increase of feed solute concentration, which is also attributable to the charge on the membrane surface.     

反渗透膜的污染及其控制

本文综合分析了引起反渗透膜污染的各种物质的形成特点及其危害，井针对每种污染提出了预防与控制措施。     

反渗透膜污染原因分析及其对策

本文结合郑州热电厂600t／h反渗透水处理系统的生产实际，对反渗透不同类型的污染：无机物沉积、有机物污染、微生物污染，分析其产生原因，对所应采取对策进行了探讨。