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。     

硬质多孔过滤介质鼓泡孔径及孔径分布的测定研究(Ⅰ)

本文 (Ⅰ、Ⅱ )分别介绍了金属丝网、金属纤维烧结毡、陶瓷膜等硬质多孔过滤介质孔径及孔径分布的测定 ,这也是生产者与使用者非常关注的一个与过滤性能有关的指标     

硬质多孔过滤介质鼓泡孔径及孔径分布的测定研究(Ⅱ)

本文(Ⅰ、Ⅱ)分别介绍了金属丝网、金属纤维烧结毡,陶瓷膜等硬质多孔过滤介质孔径及孔径分布的测定,这也是生产者与使用者非常关注的一个与过滤性能有关的指标。     

多孔陶瓷膜层状结构模型的改进

对董军航等人提出的多孔陶瓷膜层状结构模型进行了改进。比较了层高系数和单层膜平均孔径对模型计算的影响,结果表明采用单层膜平均孔径代替层高系数作为可调参数,孔径分布模拟结果有较明显的改善。     

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。     

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。     

一种孔径分布能控制的多孔陶瓷

本文介绍了一种主要是通过控制球状二次粒子原料的粒么的工艺方法制备的多孔陶瓷，其孔径分布可以控制在很狭窄的尺寸范围之内。相信这种性质具有很大的潜在使用价值。文章研究了二次粒子粒径变化对孔径分布的影响及有关问题。     

一种孔径分布能控制的多孔陶瓷

本文介绍了一种主要是通过控制球状二次粒子原料的粒径的工艺方法制备的多孔陶瓷,其孔径分布可以控制在很狭窄的尺寸范围之内。相信这种性质具有很大的潜在使用价值。文章研究了二次粒子粒径变化对孔径分布的影响及有关问题。     

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。     

孔径分布色谱法测定数据的计算机处理

以Kelvin毛细管凝聚理论和Wheeler方法为依据,圆柱形孔为模型,编制出孔径分布的计算机程序。从双气路色谱法测得的数据出法,多元线性回归拟合出等温吸附曲线,计算机按要求自动均匀在等温吸附曲线上分组取点,转换为孔体积与孔半径函数关系,即孔径分布图。     

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。     

EFFECT OF POLYVINYLPYRROLIDONE ADDITIVE ON THE PORE SIZE AND THE PORE SIZE DISTRIBUTION OF POLYETHERSULFONE (VICTREX) MEMBRANES

Investigations were made on the effect of the presence of polyvinylpyrrolidone (PVP) additive in the casting solution on the performance of polyethersulfone (PES) ultrafiltration membranes in the range of PVP/PEs weight ratio below 0.5. It was further attempted to investigate the effect of PVP additive on the size of PES polymer in the casting solution and the pore size and the pore size distribution of PES membranes. It was found that the presence of PVP additive decreases both the polymer size and the membrane pore size. Discussions were made on the mechanism of the formation of the pore based on the correlation between the polymer size and the pore size.     

EFFECT OF NONSOLVENT ADDITIVES ON THE PORE SIZE AND THE PORE SIZE DISTRIBUTION OF AROMATIC POLYAMIDE RO MEMBRANES

In this paper discussions are made on the effect of nonsolvent swelling agents on the average pore size and pore size distributions at the surface of polyamide membranes which result from casting solutions involving above nonsolvent swelling agents.

The size of the polymer aggregate in the film casting solution and the size of polymer network pores are correlated to physicochemical data of ions which constitute the electrolytes used as nonsolvent swelling agents. As such ionic properties the charge density and the free energy of transition of ions from polyamide phase to water phase were considered. The validity of the correlation is limited in a range of casting solution composition where the polymer concentration in the casting solution is close to the limiting concentration of polymer at the phase boundary and the molar ratio of the nonsolvent swelling agent to the amide group involved in the polyamide polymer is equal to or slightly more than 0.7.     

EFFECT OF ISO- AND TERE-PHTHALOYL CONTENT ON THE PORE SIZE AND THE PORE SIZE DISTRIBUTION OF AROMATIC POLYAMIDE RO MEMBRANES

Poly-m-phenylene-iso(x)-co-tere(100-xc)-phthalamide copolymers with different x values were synthesized and viscoelastic properties of the polymer solution were studied in the presence of lithium chloride nonsolvent additive in order to determine the size of the polymer aggregate in the solution. Reverse osmosis membranes were also prepared using the polymers synthesized above. The membrane performance was then tested for the separation of sodium chloride solute and reference organic solutes, in order to obtain the average pore size and the pore size distribution of the membrane. The data for the pore size were further used to calculate the length of the polymer segment in the noncrystalline region. An interesting correlation was found between the above length and the isophythaloyl content, x, of the copolymer.     

粒子烧结法制备氧化铝微滤膜

本文用粒子烧法法，制备出平均孔径０．１－０．２μｍ的管状氧化铝微滤膜，实验研究了烧结温度对膜孔径和孔径分布，孔隙率的影响，以及浸浆时间与膜厚度的关系。结果表明：提高烧地温度，平均孔径和最大孔径减小，孔隙率降低；膜厚度随着浸浆时间的平方根呈线性增加，通过多次覆盖可以有效地减少膜的缺陷。     

HYDRODEMETALLATION CATALYST PELLETS WITH NONUNIFORM RADIAL PORE SIZE DISTRIBUTION

Hydrodemetallation catalysts typically become inactive by pore mouth plugging, leaving a portion of the catalyst in the interior unutilized. By designing the pore size distribution so as to accommodate larger amount of metal deposit, improved performance can be attained. In this work the effect of nonuniform radial pore size distribution on catalyst performance is explored theoretically. Under the constraints of fixed total internal surface area and local void fraction, it is shown that catalysts with linear radial pore size distribution have larger metal deposit capacity. Furthermore, plugging of the pore mouth is delayed and therefore catalyst lifetime also increases.     

炭化条件对分子筛型活性炭孔结构的影响

以木屑及宁夏太西煤混合物为原料,以木焦油为粘结剂,经压力成型,制备柱状分子筛型活性炭,考察了炭化条件对活性炭孔径分布及其性能的影响。结果表明,炭化温度是影响分子筛型活性炭性能的关键因素,制备的活性炭具有均匀的孔径分布, <0 9nm(9 A)的孔占活性炭总孔容的 80%以上。