固体废弃物助烧的多孔SiC陶瓷膜支撑体研究进展

反应烧结可以有效降低多孔SiC陶瓷膜支撑体的烧结温度并调控其性能。本文概述了多孔SiC陶瓷膜支撑体的反应烧结原理、烧结助剂的种类及其作用机理，讨论了固体废弃物的种类及其作为烧结助剂在多孔陶瓷制备的应用，最终综述了固体废弃物助烧的多孔SiC陶瓷膜支撑体的研究进展，并对当前存在的问题及未来发展方向进行了总结与展望，为降低多孔SiC陶瓷膜支撑体的烧结温度和成本以及固体废弃物资源化利用提供参考。     

造孔剂对粉煤灰基多孔陶瓷膜支撑体的性能影响

以粉煤灰为主要原料,竹炭为造孔剂,采用干压成型法制备多孔陶瓷膜支撑体。详细研究了造孔剂添加量及烧成制度对多孔陶瓷膜支撑体的性能影响。采用场发射扫描电子显微镜、压汞仪、万能材料试验机和水通量测试装置等对多孔陶瓷膜支撑性能进行表征。当造孔剂添加量为12wt.%,烧成温度为1250℃,保温时间为20 min时,可以制备出抗折强度为25.03 MPa,平均孔径为1.25μm,水通量为3104.71 L/h.m~2.bar的多孔陶瓷膜支撑体。     

挤出法制备陶瓷膜支撑体工艺过程及影响因素研究进展

陶瓷膜因具有优良的耐高温、化学稳定性好、过滤精度高、抗化学侵蚀性及机械强度高等优点,被广泛应用于石油化工、食品、医药等行业。陶瓷膜支撑体作为陶瓷膜的核心部分,其性能对后期膜层的质量及整体应用性能起着至关重要的作用。本文综合评述了多孔陶瓷膜支撑体主要制备方法及特点,重点论述了挤出成形过程中挤出工艺、原料、添加剂、烧结等因素对多孔陶瓷膜支撑体结构及性能影响机制,并提出了需要进一步解决的问题和今后发展的方向。     

多孔氧化铝陶瓷膜支撑体在HNO3溶液中的静态腐蚀

研究了在温度为45~90℃、浓度为1~10 mol/L的HNO3溶液中,高铝多孔陶瓷膜支撑体的微观结构变化、质量损失率与时间的关系以及支撑体机械强度随其质量损失率的变化关系。结果表明,多孔氧化铝支撑体在酸性溶液中的腐蚀主要发生在支撑体颗粒之间的烧结颈部。建立了多孔支撑体的质量损失率与腐蚀时间的定量数学关系,并结合支撑体机械强度与其质量损失率的关系,对多孔支撑体在不同温度和浓度HNO3溶液中的使用寿命进行了预测。研究表明,多孔陶瓷膜支撑体具有优异的耐酸性能。     

多孔陶瓷膜支撑体在HNO_3溶液中的腐蚀性能研究

为了考察陶瓷膜在苛刻体系中的应用性能,研究了管式多孔陶瓷膜支撑体(质量分数99%Al2O3)在硝酸溶液(温度20—90℃,浓度1—10 mol/L)中的微观结构演变、质量损失率、腐蚀掉的元素成分随时间的关系,以及支撑体的孔结构、纯水通量和机械强度随其质量损失率的变化关系。结果表明主要在支撑体颗粒间的烧结颈部发生了选择性的腐蚀,在腐蚀初期其质量损失主要是由于烧结颈部中Na,Ca,Al等元素的溶解。支撑体的耐腐蚀性能与其烧结颈部的杂质含量密切相关。多孔支撑体的机械强度随支撑体在HNO3溶液中的质量损失率增大而逐渐降低。所用的多孔陶瓷膜支撑体具有优异的耐腐蚀性能。该研究为进一步提高支撑体的耐腐蚀性能及预测陶瓷膜在酸性环境中的使用性能奠定了基础。     

活性污泥对管式多孔α-Al_2O_3陶瓷膜支撑体性能影响的初步研究

以剩余活性污泥作为支撑体的成孔剂,采用滚压成型及熔膜芯法制备管状多孔α-Al2O3陶瓷膜支撑体,研究了粘结剂羧甲基纤维素(CMC)和活性污泥的加入量对氧化铝陶瓷膜支撑体品质的影响。结果表明,随着成孔剂和粘结剂的增多,支撑体孔隙率和渗透通量呈增大趋势,孔隙率最大可达43.07%,纯水通量在0.4~1.0 MPa压力下变化范围为12 786.67~37 617.84 L/(m2·h·MPa)。     

活性污泥对管式多孔α-Al_2O_3陶瓷膜支撑体性能影响的初步研究

以剩余活性污泥作为支撑体的成孔剂,采用滚压成型及熔膜芯法制备管状多孔α-Al2O3陶瓷膜支撑体,研究了粘结剂羧甲基纤维素（CMC）和活性污泥的加入量对氧化铝陶瓷膜支撑体品质的影响。结果表明,随着成孔剂和粘结剂的增多,支撑体孔隙率和渗透通量呈增大趋势,孔隙率最大可达43.07%,纯水通量在0.4~1.0 MPa压力下变化范围为12 786.67~37 617.84 L/（m2·h·MPa）。     

高岭土为助烧剂制备多孔陶瓷膜支撑体

陶瓷膜分离技术广泛应用于石油化工,食品加工,生物医学,催化过滤等领域。目前,陶瓷膜的多孔支撑体主要以氧化铝为原料。为保持较小的渗透阻力,通常使用大粒径氧化铝的,其煅烧时需要很高的温度,能耗很高,导致多孔支撑体的成本很高。为降低其制备成本,本文采用以刚玉粉(W40,平均粒径为40μm)为主要原料,以高岭土,滑石等为塑性剂和助烧剂,研究了助烧剂含量、烧结温度对多孔陶瓷支撑体的抗折强度,孔隙率以及平均孔径的影响。实验结果表明:高岭土含量的增加会导致多孔陶瓷的孔径降低和抗折强度降低;加少量的烧滑石能明显降低多孔陶瓷的烧结温度;90wt%W40粉,2wt%烧滑石,8wt%高岭土,经1510℃煅烧2h后得到的多孔陶瓷的抗折强度为153.6MPa,孔隙率为29%,平均孔径为6.6μm。所得多孔陶瓷适于用作多孔陶瓷膜支撑体。     

多通道陶瓷膜支撑体烧成制度的探讨

研究了陶瓷膜支撑体烧结温度与孔隙率/收缩率的关系，利用热重/差热分析，确定了陶瓷膜支撑体的烧结温度曲线。结果表明，在1450℃下保温2小时制备的多通道陶瓷膜支撑体无开裂，机械性能完全可满足使用要求，所制备的支撑体可以作为载体进一步开发微滤膜或超滤膜。     

泥料含水量对粉煤灰陶瓷膜支撑体性能的影响

泥料含水量是陶瓷生产中的重要参数,会影响陶瓷的收缩率、抗弯强度等性能。以电厂粉煤灰为主要原材料、糊精为造孔剂、羧甲基纤维素为黏结剂,采用挤出成型法制备了管状多孔陶瓷膜支撑体。通过控制陶瓷泥料用水量和烧结保温时间制备了不同支撑体,并对支撑体进行性能表征,考察了泥料含水量和烧结保温时间对支撑体微观结构、收缩率、孔隙率、孔径以及机械强度等性能的影响。结果表明：在水/固质量比质量为0.19时,1 150℃保温烧结2 h获得孔隙率40.5%、抗弯强度23.6 MPa、平均孔径0.41μm的支撑体。制备的支撑体应用于脱硫废水微滤处理,固体悬浮物截留率99.98%。为制备低成本粉煤灰陶瓷膜支撑体提供研究基础,有利于膜法水处理的扩大化应用。     

多孔陶瓷膜制备技术研究进展

多孔陶瓷膜具有化学稳定性好、机械强度大、耐酸碱、耐高温等优点,在石油和化学工业等苛刻环境中有着广泛的应用,多孔陶瓷膜的制备技术是推动多孔陶瓷膜产业发展的核心部分。多孔陶瓷膜制备技术的核心和关键是以提高陶瓷膜整体性能为导向,通过对陶瓷膜微结构的调控,实现陶瓷膜制备技术的突破。针对近十年来陶瓷膜领域的研究,概述了当前陶瓷膜领域在制备具有高渗透性、高渗透选择性的陶瓷膜以及陶瓷膜低成本化方面的研究进展,并对未来陶瓷膜领域的发展趋势及瓶颈性问题进行了讨论。     

陶瓷分离膜支撑体制备技术研究进展

介绍了几种无机陶瓷支撑体的制备方法,评述了这些方法的优缺点.探讨了制备过程中的几个主要因素对支撑体的孔径大小及其分布、空隙率、机械强度等重要参数的影响.并指出目前无机陶瓷支撑体的研究过程中存在的主要问题及今后的研究方向.     

氧化铝多孔支撑体的制备工艺

叙述了用挤出成型法制备无机膜支撑体的工艺,研究了原料粒径、成孔剂用量和烧结温度对所制得多孔氧化铝支撑体性能的影响。研究结果表明,用粒径小于10μm的-αA l2O3粉体,以7%碳粉为成孔剂,烧结温度为1300℃,可以成功制得孔径分布较窄、平均孔径为2.1μm、孔隙率为48.9%的多通道无机膜支撑体。     

陶瓷分离膜支撑体材料制备技术研究

对陶瓷分离膜支撑体材料的国内外研究和发展状况作了综合评述,介绍了几种陶瓷支撑体的制备方法,并评述了这些方法的优缺点.初步探讨了制备过程中的主要影响因素.     

Design and preparation of high permeability porous mullite support for membranes by in-situ reaction

The natural mineral kaolin combined with alumina additives Al(OH)₃,α-Al₂O₃ and AlF₃ was used to prepare porous mullite ceramic membrane supports using an in-situ reaction. The effects of composition and sintering temperature on the sintering behavior, pore structure, permeability and microstructure of the resulting porous mullite supports were extensively investigated. The experimental results showed that excess SiO₂ in kaolin can be consumed by adding alumina precursors, which resulted in a stiff skeleton of interlinked needle-like mullite crystals in-situ during the sintering. The needle-like mullite crystals touched each other and formed a short network, which acted as a porous skeletal network structure. This network resulted in a highly permeable porous structure. The resulting support is suitable for the preparation of asymmetric ceramic membranes. The densification and pore structure of the support can be effectively adjusted by control of the quantity of alumina precursors in the composition and the sintering temperature. Sintering the subject mullite compositions at 1500 °C for two hours resulted in support structures with an average porosity of 45.9%, an average pore size of 1.3 µm and a penetrating porosity of 35.9%.     

Review of perovskite ceramic synthesis and membrane preparation methods

In the 25 years since the first report of mixed ionic and electronic conducting ceramics, perovskite membranes underwent both research and development phases, with the latest works entering pilot trials for oxygen separation from air. During this time a number of perovskite synthesis methods were investigated from the original solid state chemistry through the more advanced and well established sol–gel route via the Pechinni method. The advances in synthesis methods were possible due to the desirable full incorporation of cations into the A and B-sites of perovskites with a general ABO₃ structure. In terms of membrane manufacturing, perovskite hollow fibres attracted a major research effort due to small membrane thickness and high fluxes. This led to a number of investigations by doping with other cations or by surface modification, all aiming at increasing oxygen fluxes. Recently, advanced ceramic processing by tape casting has led to the preparation of very thin dense films either on porous supports or as monoliths containing internal porous regions. All these developments in perovskite synthesis and membrane preparation methods, together with other types of methods requiring special equipment are addressed in this review, including an analysis of the state of the art. Finally, future challenges are discussed in terms of competing technologies and potential industrial design directions of perovskite membranes for oxygen separation from air.     

多孔陶瓷分离膜支撑体的制备研究

采用氧化铝为主要原料制备出多孔陶瓷分离膜支撑体,对原料粉体做了TG/DSC曲线分析,研究了支撑体的烧结温度对收缩率的影响及烧结温度、保温时间和原料粉体粒径对孔结构、孔径的影响,造孔剂用量对孔隙率的影响。结果表明：在烧结温度为1200℃,保温时间4h,控制造孔剂用量大于20%时,制备出孔径分布均匀,孔隙率大于50%,符合透水要求的多孔陶瓷分离膜支撑体。     

新型中空纤维陶瓷膜的制备方法

新型中空纤维陶瓷膜由于具有装填密度大、单位体积膜有效分离面积大、膜壁薄、渗透通量高和节省原料、易于实现分离设备小型化等独特优点而受到广泛关注,在用于多孔和致密陶瓷分离膜、固体氧化物燃料电池、微通道反应器、催化剂载体等方面都有着潜在的应用前景。本文在概括中空纤维陶瓷膜特点的基础上,综述了中空纤维陶瓷膜的制备方法及研究进展,着重分析比较了不同制备方法的优缺点。将相转化法应用于中空纤维陶瓷膜的制备,可实现通过一步成型制造具有自支撑非对称结构的复合陶瓷膜,有利于提高膜的渗透通量,简化膜制备工艺和显著降低制造成本。     

多孔陶瓷膜反应器用于非均相超细纳米催化的研究进展(英文)

Heterogeneous catalysts with ultrafine or nano particle size have currently attracted considerable attentions in the chemical and petrochemical production processes, but their large-scale applications remain challenging because of difficulties associated with their efficient separation from the reaction slurry. A porous ceramic membrane reactor has emerged as a promising method to solve the problem concerning catalysts separation in situ from the reaction mixture and make the production process continuous in heterogeneous catalysis. This article presents a review of the present progress on porous ceramic membrane reactors for heterogeneous catalysis, which covers classification of configurations of porous ceramic membrane reactor, major considerations and some important industrial applications. A special emphasis is paid to major considerations in term of application-oriented ceramic membrane design, optimization of ceramic membrane reactor performance and membrane fouling mechanism. Finally, brief concluding remarks on porous ceramic membrane reactors are given and possible future research interests are also outlined.     

Synthesis and Characterization of Suspension-Derived, Porous Ion-Conducting Ceramic Membranes

Porous, oxygen-ion-conducting ceramic membranes can have applications as supports for fuel cells, sensors, and thin membrane films, or as filters for membrane filtration. This paper reports on the preparation of unsupported and supported yttria-stabilized zirconia (YSZ) and yttria-doped bismuth oxide (BY) membranes with submicrometer pore sizes. Fluorite-structured BY powder that has been synthesized using the citrate method and commercial YSZ powder have been used to prepare stable aqueous suspensions. Unsupported and supported YSZ and BY membranes have been prepared from the stable suspensions of YSZ and BY. The supported BY membranes are crack free but contain small defects. Defect-free YSZ membranes that are supported on porous alumina have been prepared under controlled conditions. The average pore size is 100 nm, with a porosity of 57%, for an unsupported YSZ membrane (measured by mercury porosimetry), and 114 nm for a supported membrane (as estimated via helium permeation). The ionic conductivity of the YSZ membranes is 0.00044–0.01 S/cm in the temperature range of 600°–900°C, which is lower than that of dense YSZ disks.