Ti/Zr复合纳滤膜的制备及其性能

通过聚合溶胶路线制备出稳定的Ti/Zr(摩尔比=1:1)复合溶胶。采用浸浆法,在平均孔径为5～6 nm的片状a-Al₂O₃/g-Al₂O₃载体上制备出完整无缺陷的Ti/Zr复合纳滤膜。详细考察了焙烧温度对Ti/Zr粉体的影响,并考察了Ti/Zr复合纳滤膜的性能。结果表明:在较高烧成温度下(500℃),Ti/Zr粉体依然呈无定形态且保持微孔结构。在400℃烧成温度下制备出孔径为1.49 nm的Ti/Zr复合纳滤膜,该膜的截留分子量(MWCO)为880,纯水通量为4.3 L·m^-2·h^-1·MPa^-1。在pH=6,压力0.8 MPa的条件下,该膜对0.005 mol·L^-1的MgCl₂、CaCl₂的截留率分别为85%和78%。     

用于燃烧前CO2捕集的微孔Nb2O5膜的制备及其水热稳定性能

以五正丁氧基铌为前驱体,通过溶胶-凝胶法制备出稳定的Nb₂O₅聚合溶胶,详细考察了溶胶制备过程参数(体系酸度、水解比、反应温度、反应时间和螯合剂用量)对溶胶尺寸、稳定性以及制备重复性的影响。采用平均粒径为4.8 nm的Nb₂O₅溶胶,通过浸浆法在平均孔径为3 nm的γ-Al₂O₃中孔膜上制备出Nb₂O₅微孔膜。利用TG、XRD、NH₃吸附-脱附、CO₂吸附、吡啶吸附傅里叶变换红外光谱(Py-IR)和单组分气体渗透实验等手段对Nb₂O₅粉体及微孔膜的性能进行了表征,结果表明:在200℃、0.3 MPa条件下,350℃烧成的微孔Nb₂O₅膜对H₂的渗透率和H₂/CO₂的理想分离因子分别为3.1×10^-9 mol·m^-2·s^-1·Pa^-1和21。此外,微孔Nb₂O₅膜经150 kPa的水蒸气处理8 h后,膜的渗透性能以及H₂/CO₂理想选择性基本保持不变。     

ZrO2-TiO2复合纳滤膜在模拟放射性废水中的应用

核工业、核研究及医疗等过程会产生大量的放射性废水,会对环境和生物体造成严重伤害,必须经过合适的处理后才能排放。采用高性能陶瓷纳滤膜处理模拟放射性废水,考察了跨膜压差、pH和离子浓度等操作参数对Co²⁺和Sr²⁺截留性能的影响,并对操作参数进行了优化。所用陶瓷纳滤膜材料为ZrO₂-TiO₂复合材料,截留分子量为500,纯水渗透率为270 L·m^-2·h^-1·MPa^-1。研究表明,陶瓷纳滤膜对Co²⁺和Sr²⁺两种离子的截留率随着跨膜压差的升高而增大,膜的渗透通量随着跨膜压差的增大呈线性增加。pH变化时,截留率在一定pH范围内先降低后升高,在等电点（pH=7）附近达到最小值;pH=3的情况下,两种离子的截留率均达到最高,Co²⁺和Sr²⁺的截留率均在99%以上,而纳滤膜渗透通量保持稳定。离子截留率和渗透通量均随进料浓度的增大而减小,在2000 min的连续循环操作过程中,陶瓷纳滤膜材料的渗透通量及其对Co²⁺和Sr²⁺的截留率均维持在较高水平。陶瓷纳滤膜在放射性废水处理方面展现出了良好的应用前景。     

sol-gel法制备CeO2-TiO2/凹凸棒石复合材料的催化性能

以凹凸棒石(ATP)为载体,Ce(NO₃)₃·6H₂O和Ti(OBu)₄为原料,冰醋酸为抑制剂,采用溶胶-凝胶法制备CeO₂-TiO₂/ATP纳米复合材料。利用TG-DSC、TEM、XRD和N₂吸附/脱附仪对复合材料进行表征,考察铈钛摩尔比对所制备样品催化降解罗丹明B溶液性能的影响。结果表明,当Ce/Ti≥5/5时,具有立方萤石结构的氧化物颗粒以固溶体形式均匀分布在ATP表面,颗粒尺寸约5~10 nm;随Ti⁴⁺的进一步增加,样品中的CeO₂结晶不完全;当Ce/Ti<3/7时,样品中出现锐钛矿型TiO₂的分离相。适量的Ti⁴⁺掺杂能促进CeO₂产生较多的结构缺陷,有利于增加晶格氧空位的浓度,提高样品的催化活性。对罗丹明B的催化降解实验表明,当Ce/Ti=5/5时,样品的催化性能较好,对罗丹明B溶液的化学需氧量(COD)去除率可达96%以上。     

Al2O3溶胶对铝基磷酸盐涂层组织及性能的影响

为提高铝基磷酸盐涂层的耐腐蚀性能和力学性能,通过在铝基磷酸盐涂料中添加 Al₂O₃溶胶,经空气喷涂与热固化得到 Al₂O₃颗粒增强铝基磷酸盐复合涂层,采用 X射线衍射仪（ XRD）、扫描电镜（ SEM）、胶粘拉脱法、维氏硬度、电化学腐蚀试验和模拟海水浸泡试验考察 Al₂O₃溶胶含量对复合涂层微观组织、力学性能和耐腐蚀性能的影响。结果表明： Al₂O₃溶胶在涂层 500 ℃热固化的物相演化为 Al₂O₃溶胶 -AlOOH-Al₂O₃,随 Al₂O₃溶胶含量从 0增加到（γ相）生成的 Al₂O₃颗粒在涂层呈弥散分布;4%,复合涂层的孔隙减少,致密性提高, Al₂O₃颗粒弥散强化作用得到发挥,涂层结合强度由 15 MPa提高为 25 MPa,硬度由 38 HV提高为 65 HV;添加 Al₂O₃溶胶制备得到的铝基磷酸盐复合涂层耐腐蚀性能明显提高,自腐蚀电流密度由 2. 38×10-7 A/cm2下降至 2. 79×10^-8 A/cm²,极化电阻由 1. 95×10⁴ Ω提升至 4. 73×10⁵ Ω。     

TiO2-SiO2∶Eu3+荧光粉的制备及发光性能的研究

采用溶胶凝胶法制备TiO₂-SiO₂∶Eu³⁺发光材料，通过XRD, FTIR,荧光光谱仪的测试表征材料的结构和发光性能。结果表明，通过溶胶凝胶法成功的制备了TiO₂-SiO₂复合氧化物荧光粉。FTIR证明1070cm^-1为Si-O-Si的反对称伸缩振动，795cm^-1为Si-O-Si的对称伸缩振动，937cm^-1为Ti-O-Si特征峰。荧光光谱表明以465nm为激发波长，Eu³⁺在612nm(⁵D₀→⁷F₂)红色发光最强。Ti/Si为1∶1时，Eu³⁺掺杂浓度为4mol%时发光强度最佳。     

用废弃煤矸石制备高比表面积的SiO2-Al2O3二元复合气凝胶

以兖州煤矸石为原料,经过低温焙烧、酸浸除杂、碱熔活化,采用溶胶-凝胶法和真空干燥法制备完整的块状SiO₂-Al₂O₃二元复合气凝胶。通过X射线衍射、扫描电镜、傅里叶变换红外光谱、氮气吸附等检测手段对原料、SiO₂-Al₂O₃气凝胶及其制备过程中得到的中间产物的物理、化学特性进行表征,研究SiO₂-Al₂O₃凝胶的形成机制。实验结果表明,煤矸石经过酸浸除去了大部分的铁、钾、碱土金属等杂质。在经过碱熔活化后,煤矸石主要组分石英和高岭石均转化为非晶态,反应活性提高。制备得到的SiO₂-Al₂O₃气凝胶是以Si-O-Si、Si-O-Al网络结构为骨架的非晶态纳米颗粒聚集体,其堆积密度0.37 g·cm^-3,比表面积483 m²·g^-1,比孔容1.87 cm³·g^-1,平均孔径10.29 nm,最可几孔径9.32 nm,具有较好的介孔特征。     

α-Al2O3小孔径超滤膜低温制备与性能研究

α-Al₂O₃以低廉的价格与优秀的性能成为制备陶瓷膜的经典材料,然而α-Al₂O₃需高温驱动相变,高温会导致晶粒的过度生长与孔隙的聚结,这不利于超滤膜的制备。为制备具有高选择性的α-Al₂O₃小孔径超滤膜,采用聚合溶胶路线,通过调节溶胶合成参数影响其热处理过程中的结构转化以促进α-Al₂O₃的低温制备。在950℃下煅烧的前驱体完全转变为α-Al₂O₃。通过考察涂膜时间提升膜面完整性并采用该热处理条件制备了具有超薄分离层的α-Al₂O₃超滤膜。该膜展现出良好的分离与渗透性能,并具有较好的重复性,截留相对分子质量约为75 kDa,渗透率约为250 L·m^-2·h^-1·bar^-1。     

超亲水SiO2修饰膜的构建及其油水乳液分离性能

采用硅溶胶和多巴胺作为修饰剂,通过一步反应在微孔聚丙烯膜(MPPM)表面构建了SiO₂修饰层。利用FTIR、ESEM和EDX对膜进行了表征,发现膜表面SiO₂颗粒分布非常均匀。水/油接触角及纯水通量实验结果表明,修饰膜具有超亲水性及水下超疏油性,透水能力强,水通量大[在0.1 MPa时,水通量高达(5100±500)L·m^-2·h^-1]。油水乳液分离结果表明,修饰膜能有效分离油水乳液,在0.05 MPa时,油水乳液水通量达2830 L·m^-2·h^-1,油截留率达99.8%以上,即使过膜压力增大到0.15 MPa,油截留率也能保持在99%以上,且膜表面的油污可用水清洗除去,展现出很好的应用前景。     

溶胶-凝胶法制备Y2O3稳定ZrO2陶瓷微弧氧化封孔层

为了提高铝合金微弧氧化后的表面耐腐蚀性能,采用溶胶-凝胶法配合深紫外光化学处理法在铝合金微弧氧化膜层表面制备Y₂O₃稳定ZrO₂陶瓷封孔膜。用扫描电镜、X射线衍射、浸泡试验和电化学测试等分析手段表征其成分、相结构和表面形貌,研究复合膜层的耐蚀性。结果表明：深紫外辐照能够在较低的温度下制备出结合力好且致密的ZrO₂溶胶凝胶封孔膜,复合膜层的主要相组成为ZrO₂,与没有封孔的微弧氧化膜层相比,腐蚀电流I₀提高4个数量级,腐蚀电位E_o明显向正向移动,移动幅度为0.283,表明封孔后的涂层耐蚀性显著提高。     

EXAFS study and photocatalytic properties of un-doped and iron-doped ZrO2-TiO2 (photo-) catalysts

The local zirconium and iron arrangements of the iron-doped ZrO₂-TiO₂ system, prepared by sol–gel impregnation method, were studied by EXAFS spectroscopy. Only a tetragonal ZrO₂ structure is located on TiO₂ surface. For the iron-doped ZrO₂-TiO₂ system, the presence of the Fe-O-Fe species as well as and Fe-O-Zr species located on the surface/pre-surface region are shown; it seems that iron is heterogeneously distributed, forming small iron oxide nanoclusters and Fe_x/ZrO₂ (tetragonal) spots at the catalyst surface. The photocatalytic activity of the un-doped and iron-doped binary system ZrO₂-TiO₂ was investigated in two kind of photoreactions: the salicylic acid photooxidation and the photocatalytic reduction of Cr(VI). Different photocatalytic behaviour has been found for the un-doped and iron-doped ZrO₂-TiO₂ systems which have been explained in terms of the EXAFS study.

This study represents an example of attempt to prepare a new potential photoactive mixed oxide system, containing two ions (Ti⁴⁺ and Zr⁴⁺) with good photocatalytic activity if it is compared with commercial TiO₂ (Degusssa P25) calcined at 600 °C.     

小球藻热解油在Ni-Cu/ZrO2催化剂上的加氢脱氧

在小型固定床反应器中以Ni-Cu/ZrO₂为催化剂,对小球藻热解油进行催化加氢脱氧,以改善生物油性能。利用XRD、H₂-TPR、TG、NH₃-TPD等技术对催化剂进行了结构表征。结果表明,Cu的加入有效促进了Ni-Cu/ZrO₂催化剂活性相的表面分散,提高了该催化剂对小球藻热解油加氢脱氧反应的催化活性。在2 MPa、350 ℃反应条件下,随Cu/Ni的增大,Ni-Cu/ZrO₂的催化活性先升高后降低,Cu/Ni质量比为0.40时的催化性能最好,连续运行3 h后所得精制生物油脱氧率达82.0%。Ni-Cu/ZrO₂催化剂在反应过程中,表面结焦少,活性粒子及催化剂性能稳定,连续运行24 h后所得精制生物油脱氧率依然维持在77.0%以上。小球藻热解油经催化加氢脱氧所得的精制生物油,低位热值由31.5 MJ·kg^-1提高至35.0 MJ·kg^-1,40℃运动黏度由20.5 mm²·s^-1降至9.5 mm²·s^-1,且油品中水分更易于脱除。精制生物油中高级脂肪酸的含量减少,油品稳定性大幅提高。     

ZrO2/聚甲基丙烯酸甲酯纳米复合物:制备及其在聚合物阵列中的分散（英文）

ZrO2/PMMA nanocomposite particles are synthesized through an in-situ free radical emulsion polymerization based on the silane coupling agent (Z-6030) modified ZrO2 nanoparticles, and the morphology, size and its distribution of nanocomposite particles are investigated. Scanning electron microscopy (SEM) images demonstrate that the methyl methacrylate (MMA) feeding rate has a significant effect on the particle size and morphology. When the MMA feeding rate decreases from 0.42ml·min-1 to 0.08ml·min-1 , large particles (about 200-550nm) will not form, and the size distribution become narrow (36-54nm). The average nanocomposite particles size increases from 34nm to 55nm, as the MMA/ZrO2 nanoparticles mass ratio increased from 4:1 to 16:1. Regular spherical ZrO2/PMMA nanocomposite particles are synthesized when the emulsifier OP-10 concentration is 2mg·ml-1. The nanocomposite particles could be mixed with VAc-VeoVa10 polymer matrix just by magnetic stirring to prepare the ZrO2 /PMMA/VAc-VeoVa10 hybrid coatings. SEM and atomic force microscopy (AFM) photos reveal that the distribution of the ZrO2 /PMMA nanocomposite particles in the VAc-VeoVa10 polymer matrix is homogenous and stable. Here, the grafted-PMMA polymer on ZrO2 nanoparticles plays as a bridge which effectively connects the ZrO2 nanoparticles and the VAc-VeoVa10 polymer matrix with improved comparability. In consequence, the hybrid coating with good dispersion stability is obtained.     

Active sites in Cu/ZnO/ZrO2 catalysts for methanol synthesis from CO/H2

Among various Cu/ZnO/ZrO₂ catalysts with the Cu/Zn ratio of 3/7, the one with 15 wt.% of ZrO₂ obtains the best activity for methanol synthesis by hydrogenation of CO. The TPR, TPO and XPS analyses reveal that a new copper oxide phase is formed in the calcined Cu/ZnO/ZrO₂ catalysts by the dissolution of zirconium ions in copper oxide. In addition, the Cu/ZnO/ZrO₂ catalyst with 15 wt.% of ZrO₂ turns out to contain the largest amount of the new copper oxide phase. When the Cu/ZnO/ZrO₂ catalysts is reduced, the Cu²⁺ species present in the ZrO₂ lattice is transformed to Cu⁺ species. This leads to the speculation that the addition of ZrO₂ to Cu/ZnO catalysts gives rise to the formation of Cu⁺ species, which is related to the methanol synthesis activity of Cu/ZnO/ZrO₂ catalyst in addition to Cu metal particles. Consequently, the ratio of Cu⁺/Cu⁰ is an important factor for the specific activity of Cu/ZnO/ZrO₂ catalyst for methanol synthesis.     

Fabrication of Poly（y-glutamic acid）-coated Fe3O4 Magnetic Nanoparticles and Their Application in Heavy Metal Removal

In this study, poly（y-glutamic acid）-coated Fe3O4 magnetic nanoparticles （y-PGA/Fe304 MNPs） were successfully fabricated using the co-precipitation method. Fe3O4 MNPs were also prepared for comparison. The av erage size and specific surface area results reveal that 7-PGA/Fe304 MNPs （52.4 nm, 88.41 m2.g-1） have smaller particle size and larger specific surface area_ than Fe3O4 MNPs （62.0 nm, 76.83 mLg-1）. The y-PGA/Fe3O4 MNPs     

Processing and mechanical properties of ZrO2–TiB2 composites

In this paper, a strategy is described to develop high toughness yttria-stabilised tetragonal zirconia polycrystalline (Y-TZP) composites reinforced with hard TiB₂ particles. The experimental results revealed that fully dense Y-TZP composites with 30 vol.% TiB₂ can be obtained with a moderate hardness of 13 GPa, a high strength up to 1280 MPa and an excellent indentation toughness up to 10 MPa m^1/2 by hot pressing in vacuum at 1450 °C. The toughness of the composites can be tailored between 4 and 10 MPa m^1/2 by varying the yttria stabiliser content of the ZrO₂ matrix between 3 and 2 mol%. An optimum composite toughness was achieved for a ZrO₂ matrix with an overall yttria content of 2.5 mol%, obtained by mixing pure monoclinic and 3 mol% Y₂O₃ co-precipitated ZrO₂ starting powders. An important observation is that the thermal residual tensile stress in the ZrO₂ matrix due to the TiB₂ addition, needs to be taken into account when optimising the transformability of the ZrO₂ matrix in order to develop high toughness Y-TZP composites.     

无机杂化海藻酸钠渗透汽化膜的制备与分离性能对比

为提高海藻酸钠（SA）膜的渗透汽化分离性能,分别采用纳米氧化铝、纳米氧化锆和纳米氧化钛对SA膜进行改性,对比分析了3种不同杂化膜渗透汽化分离性能的差异,并将分离性能较好的杂化膜应用到乙酸与乙醇酯化反应脱水的体系中。系统考察了无机纳米粒子含量对SA膜渗透汽化分离性能的影响,对杂化膜进行了接触角、傅里叶红外（FTIR）、扫描电子显微镜（SEM）、热重/差示扫描量热（TG/DSC）、X射线衍射（XRD）和拉伸强度等表征与分析。结果表明,无机纳米粒子能提高SA膜的热稳定性、机械强度和渗透通量,当无机纳米粒子与SA质量比为0.3时,掺杂TiO₂、ZrO₂和Al₂O₃的杂化膜二碘甲烷的接触角依次升高,同时渗透通量也依次升高。SA-0.3Al₂O₃杂化膜亲水性较好,然而SA-0.3ZrO₂杂化膜分离性能最优,50℃下分离水含量10%的乙醇-水溶液,膜渗透通量达到336 g·m^-2·h^-1,渗透侧水含量99.97%,分离因子29990。酯化反应脱水实验表明,在80℃时,酯化反应脱水实验乙酸转化率均高于无脱水实验乙酸转化率,平衡转化率不断被打破,反应12 h后,转化率由平衡时的79.3%提高到93.9%。