高温气体净化用陶瓷纤维过滤材料的制备及性能

本文采用真空旋转抽滤成型工艺,以莫来石纤维为主要原料制备了高温气体净化 用陶瓷纤维过滤材料,研究了纤维浆料搅拌时间和烧结温度对纤维膜材料性能的影响,评价其 过滤及热震性能。实验结果表明：当纤维膜浆料搅拌 2 h 时,在 1000?C 下烧结可以制备出过抗 压强度为 4.75 MPa、透气阻力 95 Pa、气孔率为 85%、平均孔径为 70 ?m、显微结构均匀的纤维 膜材料,其除尘效率可达 99.99%,且具有良好的热震性能。     

拟薄水铝石为粘结剂成型氧化铝陶瓷的研究

探讨了利用拟薄水铝石作为粘结剂,胶凝固化后成型氧化铝陶瓷.选用柠檬酸铵为分散剂,取9wt%的拟薄水铝石,可获得固相含量为50%、粘度为960mPa·s的浆料.以硝酸为固化剂在一定的温度及时间内胶凝固化并干燥,可以得到抗弯强度为3.916MPa的生坯.并研究了拟薄水铝石对浆料粘度、生坯抗弯强度以及烧结体密度的影响.     

碳化硅质高温陶瓷膜的低温烧成

本文以碳化硅骨料、章村土系结合剂和核桃壳粉为原料,通过等静压成型工艺和 低温烧结制备了碳化硅质高温陶瓷膜材料。研究了成型压力对坯体强度以及成型压力和烧成温 度对膜材料强度、孔径、气孔率和透气阻力的影响。结果发现,当成型压力为 70 MPa、烧成温 度为 1250~1270?C 时,制品综合性能较优。     

硅酸铝陶瓷纤维过滤管的制备与表征

本文研究制备陶瓷纤维过滤管所用硅酸铝纤维、硅溶胶和水之间的最佳配比及最佳成型工艺参数。并对陶瓷纤维过滤管的气孔率、孔径以及抗弯强度进行测试,运用SEM对试样进行微观分析。研究确定的最佳配比是硅溶胶含量为68wt%,硅酸铝纤维含量为12wt%,水含量为20wt%,真空抽滤成型时最佳抽滤压力为0.08MPa,最佳抽滤时间为5min。     

非烧结陶瓷纤维多孔过滤材料的制备与性能

采用真空抽滤成型和非烧结低温固化工艺,以硅酸铝陶瓷纤维、硅溶胶、羧甲基纤维素为主要原料,制备了陶瓷纤维多孔过滤材料。研究了原料配比和工艺参数对材料性能的影响。结果表明：最佳配方比例为陶瓷纤维2.5wt%,硅溶胶50wt%,水 47wt%,羧甲基纤维素0.5wt%,在抽滤时间为5 min,固化温度为150℃的条件下﹐可获得非烧结陶瓷纤维多孔过滤材料,其气孔率、抗折强度和压降分别为80.22%、1.83 MPa和 130 Pa。该制备方法为工业化生产高温烟气过滤材料提供了新的选择。     

溶胶-凝胶法制备ZrB2-SiC复合材料的研究

采用溶胶-凝胶法制备ZrB<,2>-SiC复合材料,主要分析pH值、分散剂、固相含量、有机单体含量对ZrB<,2>-SiC浆料粘度的影响.实验结果表明,当pH值为10.3,分散剂含量为0.92 wt%,有机单体含量为3.2 wt%时,就可以制得固相含量为45 vol%,粘度为608 mPa·s的ZrB<,2>-SiC浆料.     

泡沫凝胶注模成型工艺在多孔氧化铝陶瓷制备中的应用研究

本文介绍了泡沫凝胶注模成型工艺,研究了分散剂、固相含量等工艺参数对浆料粘度的影响,研究得出浆料中固相含量为55%时,以PMAANa为分散剂,可获得100 mPa·S低粘度高固相的陶瓷浓悬浮液;同时还研究了引发剂对凝胶固化反应的影响,实验结果表明引发剂在0.3~0.4%时聚合时间较适宜;重点探讨了发泡剂、固相含量、引发剂等对多孔氧化铝陶瓷性能的影响。     

CaO-B2O3-SiO2玻璃陶瓷系生料带流延工艺研究

采用正交实验研究固含量、粘结剂和增塑剂对CBS(CaO-B2O3-SiO2)玻璃体系浆料粘度、生坯性能影响.利用STATISTICA 6.0分析表明:固含量、PVB和DBP的交互作用分别对浆料粘度和生料带的可揭膜程度影响最大,单因素及其交互作用对生坯密度均无显著影响.固含量50wt%.相对CBS玻璃粉料添加2wt%蓖麻油,7.5wt%PVB、4.5wt?P时,制备的浆料粘度为2.1 Pa.s.较适合流延,生坯体积密度达到1.6g.cm-3,且生料带较易从流延机上剥离.875℃低温烧结试样,在100Hz微波频率下测试,介电常数为6.56,介电损耗1.57×10-3.     

ZrO_2表面改性及凝胶注模研究

凝胶注模成型工艺能够制备出高强度,高致密性,且形状复杂的氧化锆陶瓷。粉体团聚对凝胶注模成型工艺存在不良影响,粉体团聚导致陶瓷内部产生缺陷,导致致密性、均匀性变差,力学性能降低。本文通过对氧化锆粉体表面改性,改善粉体团聚,将改性粉体用于凝胶注模成型,制备出低粘度浆料。通过SEM、粘度仪、显微镜等仪器,对强度、粘度及粉体分散情况进行表征。结论 :当钛酸酯偶联剂加入量为0.4 wt%时,粉体团聚情况以及粘度达到最佳,当固相含量为50%时,粘度达到557.6 mPa·s,抗弯强度达到710.08 MPa,洛氏硬度达到92 HRB;断面观察,改性后陶瓷内部颗粒间结合较为紧密,结构均匀。     

PVB对Ca-Ba-Mg-Al-B-Si-O玻璃/Al_2O_3材料性能的影响

以Ca-Ba-Mg-Al-B-Si-O玻璃和Al_2O_3为原料,加入流延剂后流延成型生瓷带,采用低温烧结法制备了玻璃/Al_2O_3系介电陶瓷材料。设计添加PVB粘结剂与KH-570型硅烷偶联剂协同优化流延工艺,重点研究了PVB粘结剂对浆料特性、生瓷带性能以及生坯烧结性能的影响。随着PVB相对分子量降低,浆料固含量增加,生瓷带体积密度增加,拉伸强度与断裂伸长率逐渐降低。PVB粘结剂中的PVB、PVA、PVAc基团在溶剂中溶解,产生一定粘度,使玻璃/Al_2O_3浆料具备合适流延的粘度。添加PVB-5s的玻璃/Al_2O_3浆料的固含量为67 wt%,相应生瓷带体积密度为1.92 g·cm~(-3),拉伸强度为1.42MPa,生瓷带表面光滑致密,生坯于850℃烧结良好,烧结体微观结构致密,介电性能优良,因此该体系材料比较适合用作低温共烧陶瓷材料。     

A STUDY ON THE PREPARATION OF NON-SUPPORTED γ-ALUMINA MEM BRANES BY SOL-GEL METHOD

A series of nonsupported γ-alumina membranes were prepared by using sol-gel method. The influences of preparation parameters including acid/alkoxide ratio, water/alkoxide ratio, alcohol/alkoxide ratio, hydrolysis temperature, and calcination condition were investigated. From the experimental results, it indicated that the acid/alkoxide ratio and calcination temperature play important roles on controlling the microstructural properties of the membrane. The y-alumina membranes can be obtained under various hydrolysis temperatures even below 80°C, and the minimum pore size occurred at about 60°C of hydrolysis. With the same amounts of acid, both the particle size of the sol and pore size of the membrane obtained by the PMU route were slightly smaller than that by the DCS route. The relationship among preparation conditions, properties of boehmite sols and mircostructure of membranes were also discussed.     

陶瓷分离膜的制备工艺进展及市场应用

本文简要叙述了陶瓷发离膜制备工艺进展,目前发展现状及陶瓷分离在微滤、超滤及气体分离等领域中的市场应用,展望了今后陶瓷分离膜制备技术及市场应用发展趋势。     

多孔陶瓷过滤材料

介绍了多孔陶瓷和陶瓷分离膜的特点、分类、物理性能、工艺影响因素及过滤性能和应用情况。     

Process Design for the Production of Prebiotic Oligosaccharides in an Enzyme Membrane Bioreactor: Interaction between Enzymatic Reaction and Membrane Filtration

Appropriately designed and operated enzyme membrane bioreactors (EMBRs) can fully utilize the activity of free, soluble enzymes while maximizing enzyme reusability and simultaneously removing the enzyme-free product in situ. A filtration model system was applied to determine critical EMBR design factors suitable for continuous enzymatic production of prebiotic fructo-oligosaccharides. The filtration flux and separation efficiency were investigated in terms of the membrane cutoff rating. In addition, the influence of operational conditions on enzyme activity was also determined.     

分离用金属陶瓷复合膜及研究进展

金属陶瓷复合膜是由金属膜及表面陶瓷活性膜层复合而成,综述金属膜制备方法及金属膜表面溶胶凝胶法制备陶瓷活性层膜制备技术,为金属陶瓷复合膜制备提供理论意义。论述国内外金属陶瓷复合膜研究进展,对金属陶瓷复合膜制备工艺技术及应用范围展望。     

The effects of diatomite addition on the pore characteristics of a pyrophyllite support layer

Recently, porous ceramic membranes have become a subject of special interest due to their outstanding thermal and chemical stability. To alleviate the manufacturing cost issues of these porous ceramic membranes, recent research has been focused on the utilization of low cost natural materials. Therefore, in this paper, we report the results of our efforts to determine whether we could utilize diatomite as a pore former and whether we could prepare a pyrophyllite–diatomite composite support layer that could effectively control the largest pore size and permeability. The pore characteristics of the specimens were studied by scanning electron micrography, mercury porosimetry, and capillary flow porosimetry.     

连续发酵生产酒精的陶瓷膜分离反应器的研制

一、前言为了提高酒精生产能力,人们开发出各种各样的新型反应器。其中,有膜分离技术与反应器相结合的产物——中空纤维膜反应器,因其具有较大的过滤面积,细胞浓度高,生产能力强,很有生命力。但其机械强度不好、细胞分布不均匀,经常发生泄漏等缺点。本文用高温烧结的陶瓷管代替中空纤维,研制成新型的陶瓷膜分离反应器。二、反应器的研制     

Membrane Fouling in the Reclamation of Secondary Effluent with an Ozone-Membrane Hybrid System

Abstract

The current research is a pilot scale study on membrane fouling in an ozone-ceramic membrane hybrid system, aiming at the reclamation of secondary effluent which contains abundant organic substances and bacteria. Compared with the microfiltration process with 30 mg O₃/L feed, the microfiltration without ozone sustained for a longer period of time and produced greater filtrate volume, while all other conditions were kept constant. The results of size exclusive chromatography (SEC) show that the number of large molecules increases after ozonation; this part of organic molecules may contribute more to 0.1 µm membrane fouling. Other evidence proves that ozone brings about the lysis of bacteria. This may account for the increase in the number of large organic molecules after ozonation.     

CO2 capture based on Al2O3 ceramic membrane with hydrophobic modification

In this paper, Al₂O₃ ceramic membrane is modified to hydrophobicity by grafting 1 H,1 H,2 H,2 H-perfluorodecyltriethoxysilane. And its properties are characterized in detail. CO₂ capture performance of ceramic membrane is investigated by experiments. Results show that wetting resistance after modification is significantly improved, and contact angle increases from the initial 49.8–130.9°. However, hydrophobic modification has no significant effect on the crystalline phase, surface morphology and pore size distribution of the ceramic membrane. With ethanolamine (MEA) as absorbent, CO₂ mass transfer rate and capture efficiency using modified hydrophobic ceramic membrane are 46.6 × 10⁻³ mol/(m²·s) and 98.0%, showing significantly increase compared to the original membrane. After 72 h immersion in MEA solution, quality of ceramic membrane does not change significantly. And there is almost no change in average pore size. We believe this study will provide a reference for the industrial application for CO₂ capture by gas-liquid membrane contactor with ceramic membrane.