陶瓷膜孔径常用测试方法综述

孔径大小及孔径分布是陶瓷膜材料的重要技术指标，决定了陶瓷膜的过滤能力及适用工况。因此，准确测试陶瓷膜孔径对于陶瓷膜材料的工艺开发和实践应用具有重要意义。文中综述了几种常用的陶瓷膜孔径测试方法，包括压汞法、气体吸附法、电镜观测法、泡点法、气体排除法和液液置换法等，比较了各种测试方法的优缺点，认为气体排除法和液液置换法是最适用于陶瓷膜孔径测试的方法，并对陶瓷膜孔径测试方法提出了展望。     

多孔陶瓷孔径及其分布测定方法研究进展

孔径及其分布决定了多孔陶瓷的性能及应用,因此对其测定和定量表征非常重要。本文综述了多孔陶瓷孔径及孔径分布的常见测定方法,包括气泡法、压汞法、气体透过法、气体吸附法、气体渗透法、液-液法、悬浮液过滤法、X射线小角度散射法、核磁共振成像法、X射线断层扫描法以及电子显微镜图像分析法。比较了各种测试方法的优缺点,认为电子显微镜图像分析法是最直接有效的测定方法,并对多孔陶瓷的测试表征方法提出了展望。     

氮气吸附法和压汞法测定Al2O3载体孔结构

作为催化剂载体的活性氧化铝,其孔径分布主要集中在中孔范围内,压汞法和氮气吸附法是测定多孔材料比表面积、孔径及其分布的经典方法,采甩压汞仪和比表面积、孔径测定仪对活性氧化铝载体孔结构进行测定。氮气吸附法采用BET原理进行比表面积测定,采用BJH原理进行孔径分布和孔容的测定,压汞法采用Wasburn公式测定比表面、孔径分布和孔容。对两种方法实验结果进行了讨论,认为氮气吸附法更适合氧化铝载体孔结构的测定。     

负载型TiO2复合陶瓷膜的制备与表征

采用料浆浇注法制备了硅藻土－莫来石（K－M）陶瓷支承体管，溶胶－凝胶法在其上制备了负载型TiO2复合膜，并采用ESEM、压汞法、IR和纯气体渗透性能测试装置对其进行了表征。结果表明：TiO2/K-M复合陶瓷膜成膜情况良好，孔径分布比较均匀；支承体和TiO2膜孔径分别集中分布在2．01μm和37nm左右；TiO2膜层与支承体存在键联和相互作用；TiO2膜层的气体渗透为努森扩散和粘性流共同控制。     

液液界面法测超滤膜孔径及孔径分布

本采用液液界面法，利用毛细管现象测定了截留分子量为２×１０＾４和５×１０＾４聚砜超滤膜ＰＳ－２，ＰＳ－５的孔径及孔径分布。结果表明，利用水－正丁醇体系能测定超滤膜的孔径及孔径分布，并且具有操作简便，测试压力接近膜工作压力的优点，对于ＰＳ－２超滤膜，测试压力达０．５ＭＰａ即能得到膜完整的孔径分布曲线。     

气体泡压法测定无机微滤膜孔径分布研究

本文采用气体泡压法测定了孔径０．１５μｍ的α－Ａｌ２Ｏ３无机微波膜孔径分布，研究了乙醇，异丁醇及甲苯三种浸润剂的影响，并与压汞法的结果进行了比较。结果表明：泡压法与压汞法测是的结果一致；乙醇、异丁醇和甲苯得到的平均孔径比较接近，而异丁醇由于蒸汽压和表面张力较小，毒性较低是一咱比较理想的浸润剂。     

中空纤维膜孔径及其分布的测定

研究了中空纤维膜孔径及其分布的测定方法．液液置换法。通过研究建立了能够准确描述跨膜压差与流体通量的数学模型，采用不同的液液体系（正丁醇．纯净水、正戊醇．纯净水和正己醇一纯净水）测定了膜孔径为0.2μm的中空内压疏水膜的孔径及其分布，并对测试结果进行比较分析。实验研究结果与电镜扫描结果符合较好，研究表明液液置换法装置简单、易操作、是一种理想的膜孔径分布表征方法。     

制备工艺对多孔碳化硅材料性能的影响

研究了骨料粒径、添加剂种类、质量分数对陶瓷管性能的影响。采用自制装置分别测定了孔径分布、平均孔径、孔隙率和气体通量。用SEM观察其表面形貌。结果表明,使用较细的碳化硅颗粒,气体通量减小,抗弯强度增加;随着造孔剂质量分数的变化,多孔碳化硅陶瓷管的性能也有明显的不同,最佳添加量为10%左右。增加烧结结合剂的加入量,气体通量和抗弯强度均下降。     

多通道陶瓷超滤膜孔径分布及截留率测定

本文对工业化多通道陶瓷超滤膜进行了研究,以异丁醇－蒸馏水体系用液－液排除法测定了超滤膜的孔径及孔径分布,对同一膜管及体系,进行了重复性实验,测定了膜的截留率,比较了截留率与孔径及孔径分布的关系,讨论了操作条件对截留率的影响,为工业化膜的制备及选取提供指导。     

超滤膜孔径及其分布的测定方法：Ⅱ.两种测定方法设计

设计了连续气流法和混合探针分子分光光度法，可测定超滤膜孔径及其分布。     

Porosimetric Characterization of Inorganic Membranes

Abstract

This paper deals with the evaluation of pore size and pore size distribution of inorganic membranes by liquid-liquid displacement porometry. Carbon and ceramic membranes were tested with a fully automatic porometer, and different results were obtained depending on the type of membrane. Membranes were also examined with the aid of a scanning electron microscope. The results of porosimetric measurements are discussed in conjunction with those of microscopic observations.     

工业化陶瓷超滤膜的表征

以液-液排除法测定工业化陶瓷超滤膜的孔径及孔径分布，比较了两种渗透体系对测定结果的影响；用已知分子量标准物质考察了不同膜的截留行为，获得了各膜的切割分子量值，并分析了截留率与孔径的对应关系，为工业化陶瓷膜的开发提供依据。     

Pore Size and Pore-Size Distribution in Microfiltration Membranes

Abstract

This paper deals with the characterization of microfiltration membranes by porosimetric measurements. Different methods have been used to test the membranes: the Poiseuille-Knudsen method, the mercury intrusion method, and liquid displacement porometry. Membranes were also examined with the aid of a scanning electron microscope. On the basis of the results obtained, liquid displacement porometry was proven the only method applicable for a proper characterization of the membranes.     

Modeling of the Relationship Between Pore Size Distribution and Thickness of Ceramic MF Membrane

The pore size distribution(PSD)measured by the gas bubble point(GBP)method ofceramic microfiltration(MF)membranes prepared by suspension technique was found to be signifi-cantly influenced by the membrane thickness.A culm-like model for pore structure was introduced tocharacterize the membrane pores instead of the conventional model which does not reflect the radiusvariation along the pore passages and is unable to explain the thickness effect on the membrane PSD.A laminate structure,taking the culm-like model for pore structure into consideration,was hypoth-esized for ceramic MF membranes.A mathematical model was then established to quantitativelydescribe the relationship between the membrane number PSD and the membrane thickness.Goodresults were obtained for the correlation of mean pore size and simulation of the PSD for ceramicMF membranes.     

Pore‐size evaluation and gas transport behaviors of microporous membranes: An experimental and theoretical study

A modified gas‐translation (GT) model based on a GT mechanism was successfully applied to the pore‐size evaluation and gas transport behavior analysis of microporous membranes with different pore‐size distributions. Based on the gas permeation results of three microporous membranes derived from different alkoxides, the effects of activation energy and the selection of a standard gas on the pore‐size evaluation were discussed in a comparative study. The presence of nano‐sized defects had an important influence on the gas permeation performance of microporous membranes, depending largely on the original pore size of the membrane in question. Moreover, the gas‐separation effect of the pore‐size distribution in a silica membrane was theoretically studied and revealed a significant increase in gas permeance for relatively large gas species but not for small ones. © 2015 American Institute of Chemical Engineers AIChE J, 61: 2268–2279, 2015     

Pore Structure and Permeability of an Alumina Fiber Filter Membrane for Hot Gas Filtration

The pore structure and permeability of an alumina-fiber-based hot gas filter membrane containing an acid phosphate binder were characterized using capillary flow porometry. The smallest pore diameter was 1.24 ± 0.06 m; the largest pore diameter (bubble point pore diameter) was 23 ± 1 m. The pore size distribution was narrow, with almost all pores ranging from 2 to 4 m, and the mean flow pore size 2.6 ± 0.1 m. The Darcy permeability constant for air through the membrane was (114 ± 6) × 10^–9 cm².     

支撑体孔径大小对Al2O3微滤膜完整性的影响

无机微滤膜不仅具有优良的热稳定性、机械稳定性和结构稳定性,而且化学稳定性高,耐腐蚀,不会被微生物分解,使用寿命较长,易于清洗和再生,更重要是无机微滤膜无毒．因此,它在食品、生化制药、催化反应等领域中作为物料的预处理和催化载体有着广阔的应用前景．然而,无机微滤膜真正起作用的是一层薄膜,     

Properties of polyethersulfone ultrafiltration membranes modified with polyethylene glycols

Polyethersulfone ultrafiltration membranes have been prepared using polyethylene glycols (PEGs) of 400, 1000, and 10,000 gmol, as additive with dimethylacetamide as solvent. Infrared analysis proves that PEG leaves almost completely the surface of the membranes after 24 h of water immersion. Scanning electron microscopy, contact angle, and liquid–liquid displacement porometry have been used to characterize the membrane morphology, surface hydrophilicity and porous structure. The relative flux reduction factor, flux, retention—of PEG (20,000 and 35,000 g/mol) and bovine serum albumin (67,000 g/mol)—and pure water permeability have been measured for the membranes. Results show that the addition of PEG increases slightly hydrophilicity and decreases pore size and narrows the corresponding pore size distribution while thickening the skin layer, in spite of the fast disappearance of the added PEG form the membrane surface. The resulting flux and pure water permeability are higher when middle size PEGs are added but decrease again when very high molecular weight (MW) PEGs are added. Retention decreases initially for increasing MWs of PEG although for very long PEG chains (MW of 10,000 g/mol) retention increases again. After filtration, the membranes with PEG added showed a lower relative flux reduction that decreases for increasing MW of the added PEGs. © 2013 Society of Plastics Engineers. POLYM. ENG. SCI., 54:1211–1221, 2014. © 2013 Society of Plastics Engineers