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高岭土制备4A型沸石的研究 总被引:2,自引:0,他引:2
以广东省茂名高岭土为原料,经过煅烧活化、成胶反应、晶化、过滤等工序,制备出高品质的4A沸石。为了缩短4A沸石的生产时间,还进行了高岭土煅烧活化,制得的偏高岭土加碱直接高温高压反应制备4A沸石实验,结果表明此新工艺产品性能优良,钙镁离子交换性能高,生产周期短。此外,论文还考察了超声波对传统工艺制4A沸石的影响。 相似文献
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高炉渣是高炉炼铁过程中的副产品,是一种复杂的硅酸盐,高炉渣酸浸后的滤渣是硅凝胶,可以作为硅源,从而合成沸石。以高炉渣为前驱体,采用碱熔融-水热法合成不同形貌沸石,通过X射线衍射分析、扫描电子显微镜等表征手段探讨了最佳合成条件及反应机理。结果表明,体系中硅铝比为影响沸石结构种类的关键因素,n(Si)/n(Al)=0.4~1.2范围内,能够合成A型沸石;n(Si)/n(Al)=1.6~2.0范围内,能够合成八面沸石;n(Si)/n(Al)=1.4处为A型与八面沸石共存体系;八面沸石的形成需经过溶解—成核—结晶等几个过程,属于双相转化反应机理;合理控制晶化温度可将八面沸石转变为P型沸石。 相似文献
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以无水氯化铝和异丙醚为原料,采用非水解溶胶-凝胶法制备出氧化铝凝胶。其经800℃煅烧才析出少量γ-Al2O3晶体,γ-Al2O3向α-Al2O3晶型转变在1200℃附近,经900℃煅烧后比表面积仍高达145m2/g,具有介孔结构。以该高活性氧化铝凝胶作为铝源,采用碳热还原氮化工艺合成氮化铝粉体。结果表明,氧化铝凝胶经300℃预煅烧,按n(C)/n(Al)=7.8与碳黑混合,在流量80mL/min高纯N2中,于1450℃还原氮化2h便可合成出平均粒径在400nm的高纯六方相AlN粉体。 相似文献
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以Y(NO3)3.6H2O、Al(NO3)3.9H2O和柠檬酸为原料,采用凝胶燃烧法合成单相钇铝石榴石(Y3Al5O12,YAG)纳米粉体。采用红外光谱、差热分析、X射线衍射、扫描电镜等测试手段对前躯体干凝胶和YAG粉体进行表征,探讨溶胶-凝胶的均质化转变以及YAG相的结晶温度等。结果表明:柠檬酸与Y3+和Al3+以单齿方式进行络合,实现了溶胶-凝胶的均质化转变;前躯体粉末于750℃低温下开始直接由无定形态转变为立方晶系YAG相,没有YAlO3和Y4Al2O9等杂相存在;900℃煅烧2 h得到颗粒呈类球形状,粒径为50 nm左右的YAG粉体。 相似文献
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采取铝热原位合成的方法,以钛白粉和铝粉为原料原位合成制备TiAl/Al2O3复合材料。通过XRD分析了不同温度下反应过程及烧结样品的物相形成规律。分析结果表明:在750℃条件下反应时,原料中心部分变成了黑色,反应生成了钛的低价氧化物。随着温度的升高逐渐形成了部分TiAl金属间化合物和Al2O3。当温度达到1250℃时,反应比较充分,主要生成了TiAl金属间化合物和Al2O3,原位合成了TiAl/Al2O3复合材料。 相似文献
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碳酸铝铵热分解制备α-Al2O3超细粉 总被引:33,自引:0,他引:33
研究了以硫酸铝铵和碳酸氢铵为原料合成碳酸铝铵的工艺条件.在实验条件范围内,将硫酸铝铵溶液以低于1.2L.h-1的速度加入到碳酸氢铵溶液中,可合成碳酸铝铵;在其它操作条件下,获得的产物为γ-AlOOHγ-AlOOH升温过程中的物相变化次序为:γ-AlOOH→γ-Al2O3→δ-Al2O3→θ-Al2O3→α-Al2O3;而碳酸铝铵的相变次序为:碳酸铝铵→无定型Al2O3→θ-Al2O3→α-Al2O3碳酸铝铵转变为θ-Al2O3和α-Al2O3的温度均比γ-AlOOH低约100℃γ-AlOOH在1200℃煅烧1h方可完全转变为α-Al2O3,其颗粒尺寸为150um;粉体经1450℃、2h烧结相对密度为84.46%;而碳酸铝铵在1100℃煅烧1h就可完全转变为α-Al2O3,其颗粒尺寸为70um,粉体在相同的烧结条件下相对密度可达97.80% 相似文献
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Multiwall carbon nanotubes (MWCNTs) were functionalized with a photosensitizer, rosebengal (RB), and folicacid (FA), an anti-cancer
drug simultaneously and individually, which was characterized with various analytical instruments like Fourier Transform Iinfrared
(FTIR) spectroscopy, UV–Vis spectroscopy, Thermogravimetric analysis (TGA), Photoluminescence (PL) spectroscopy, X-ray photoelectron
spectroscopy (XPS), and Transmission electron microscopy (TEM). FTIR spectra confirmed the chemical modification of MWCNT.
The chemical functionalization of MWCNT with RB was further supported by UV–Vis and PL spectra. 相似文献
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Durga Bhakta Pokharel Liping Wu Junhua Dong Xin Wei Ini-Ibehe Nabuk Etim Dhruba Babu Subedi Aniefiok Joseph Umoh Wei Ke 《材料科学技术学报》2021,66(7):202-212
The effect of addingd-fructose to simulated body fluid(SBF) on the corrosion behavior of AZ31 magnesium(Mg) alloy at 37.C and at a pH of 7.4 was studied by potentiodynamic polarization(PDP), electrochemical impedance spectroscopy(EIS), potentiostatic polarization and hydrogen(H2) collecting techniques,Raman spectroscopy technique, scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS), X-ray diffraction(XRD), X-ray photoelectron spectroscopy analysis(XPS) and Fourier transformed infrared(FTIR). The results demonstrated that the addition of fructose enhanced the deposition of phosphates forming thick and compact corrosion products, which inhibited the transmission of aggressive ions into the Mg substrate. As a result, both the anodic dissolution of Mg and negative difference effect(NDE) were suppressed. Thus, the corrosion resistance of AZ31 Mgalloy in SBF was significantly improved. 相似文献
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Hung-Hsia Chen R. Anbarasan Long-Sheng Kuo Ping-Hei Chen 《Journal of Materials Science》2011,46(6):1796-1805
ε-Caprolactone (CL) was subjected to ring opening polymerization (ROP) under inert (nitrogen) atmosphere at 413 K for 1 h
in the presence of stannous octoate (SO) as a catalyst and Eosin Y, a xanthenes type dye as a novel chemical initiator. The
ROP was carried out at two different experimental conditions, namely at various concentrations of initiator and monomer, to
get more scientific information from the resultant product. Thus, obtained Eosin Y conjugated poly(ε-caprolactone) (PCL) was
characterized by different analytical tools like FTIR spectroscopy, NMR spectroscopy, gel permeation chromatography (GPC),
UV–Visible spectroscopy, photoluminescence (PL) spectroscopy, X-ray photoelectron spectroscopy (XPS), and differential scanning
calorimetry (DSC). Finally, the morphology of the Eosin Y conjugated PCL was studied by scanning electron microscopy (SEM).
The binding constant (K) was determined from both UV–Visible spectroscopy and PL spectroscopy, and the static quenching mechanism was proposed. The
number of binding site (n) was also determined from PL spectroscopy and the results were compared with the FTIR-RI method. 相似文献
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Liu Z Zhang X Yang X Ma Y Huang Y Wang B Chen Y Sheng J 《Journal of nanoscience and nanotechnology》2010,10(9):5570-5575
In this paper, a novel molecular wire comprising an isolated straight polystyrene (PS) chain encapsulated by a single-walled carbon nantube (SWNT) was prepared. The interaction of the PS chain with the SWNTs was systematically characterized using transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and Raman spectroscopy. 相似文献
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1,8,15,22-Tetra-aminophthalocyanine/graphite (ZnTAPc/Gr) composites were prepared by chemical grafting method. The property of styrene oxidation in the presence of tert-butyl hydroperoxide (TBHP) as an oxidant was studied. The prepared catalysts were characterized by UV-Vis spectroscopy (UV-Vis), X-ray diffraction (XRD), infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), Raman spectroscopy, UV-vis diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The obtained ZnTAPc/Gr composites were employed as catalyst for styrene oxidation in presence of tert-butyl hydroperoxide (TBHP) as oxidant. The results showed that styrene was oxidized efficiently in the ZnTAPc/Gr-TBHP system. The enhancement of the catalytic activity of ZnTAPc/Gr composites was investigated in terms of different oxidation conditions. It was found that the optimum oxidation condition was 0.04 g catalyst, 10 h reaction time and reaction temperature of 100°C. Under this condition, the conversion and the selectivity of styrene oxide was up to 73% and 84%. 相似文献
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在303~393 K温度范围内,采用变温傅里叶变换衰减全反射红外光谱技术(ATR-FTIR)研究了二甲基硅油的一维红外光谱、二阶导数红外光谱、四阶导数红外光谱和去卷积红外光谱。实验发现,在1800~600 cm~(-1)范围内,二甲基硅油主要存在CH_3伸缩振动模式(νCH_3)、CH_3变形振动模式(δCH_3)、CH_3摇摆振动模式(ρCH_3)、Si-O伸缩振动模式(νSi-O)和Si-C伸缩振动式(νSi-C)等5种红外吸收模式,其中782 cm~(-1)和789 cm~(-1)处的红外吸收峰归属于二甲基硅油νSi-C。以二甲基硅油νSi-C为研究对象,进一步开展相关二维红外光谱的研究。结果发现,随着测定温度的升高,二甲基硅油νSi-C红外吸收强度的变化快慢顺序为:789 cm~(-1)782 cm~(-1)。本项研究拓展了ATR-FTIR技术在二甲基硅油热变性方面的研究范围。 相似文献
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高度支化水性聚氨酯的合成及性能 总被引:2,自引:0,他引:2
以甲苯-2,4-二异氰酸酯(TDI)、聚碳酸酯二醇(PCDL)、二羟甲基丙酸(DMPA)和聚醚胺(ATA)为原料,采用A2+B3法合成了具有高度支化结构的水性聚氨酯(HBAPU)乳液。用红外光谱(FT-IR)对产物结构进行表征;用光子相关光谱(PCS)研究了乳液的稳定性能,NCO/OH=1.3,w(DMPA)=6%时可以得到稳定的HBAPU乳液;采用旋转黏度计、差式扫描量热仪(DSC)、热失重分析仪(TG)、电子拉力机对产物的流变行为和各种性能进行了测试。结果表明,相对于线性水性聚氨酯(LAPU),HBAPU产物具有较低的黏度、良好的热稳定性、较高的Tg和拉伸强度。 相似文献
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[Bis(salicylidene)nickel(II)] was used as a precursor to prepare nickel sulfides nanoparticles of average size 20 nm by a chemical process in oleylamine. The products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectroscopy (UV-vis) and photoluminescence (PL) spectroscopy. Magnetization measurement indicates that both of the α-NiS and Ni3S4 nanoparticles show pramagnetism due to the size effect. 相似文献
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Composite Bi@Bi2O3 microspheres have been synthesized via a microwave-assisted solvothermal route. The Bi@Bi2O3 microspheres had a narrow size distribution in the range 1.2–2.8 mm. Glucose was selected as the reductant, BiCl3 as the bismuth source, and ethylene glycol (EG) as the solvent in the synthesis system. The as-synthesized sample was characterized
by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM),
transmission electron microscopy (TEM), particle diameter distribution, energy dispersive X-ray spectroscopy (EDS), ultraviolet-visible
(UV-vis) spectroscopy, and photoluminescence (PL) spectroscopy. The photocatalytic activities of the Bi@Bi2O3 microspheres were evaluated by the photodegradation of rhodamine B (RhB) and methyl orange (MO) dyes under UV light irradiation.
The degradation reached ∼96.6% for RhB and 100% for MO after 4 h reaction in the presence of the as-synthesized Bi@Bi2O3 microspheres. 相似文献
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硅氧树脂 Si-O 键伸缩振动模式ATR红外光谱研究 总被引:1,自引:0,他引:1
在303~393 K 温度范围内,采用变温傅里叶变换衰减全反射红外光谱(ATR-FTIR)技术分别测定硅氧树脂的一维红外光谱、二阶导数红外光谱和四阶导数红外光谱。研究发现,在1800~600 cm-1范围内,聚硅氧树脂主要存在着 CH 3伸缩振动模式(νCH3)、CH 3变形振动模式(δCH3)、CH 3摇摆振动模式(ρCH3)、Si-O 伸缩振动模式(νSi-O )和 Si-C 伸缩振动模式(νSi-C )。在1100~1000 cm-1范围内,以νSi-O 为研究对象,研究了温度对硅氧树脂分子结构的影响。实验发现,随着测定温度的升高,硅氧树脂νSi-O 的主要红外吸收频率出现了明显的红移现象。进一步研究了硅氧树脂νSi-O 的二维红外光谱,考查温度对于νSi-O 红外吸收强度的影响。研究发现,随着测定温度的升高,硅氧树脂νSi-O 红外吸收强度的变化快慢顺序为:1024 cm-1>1096 cm-1>1010 cm-1>1076 cm-1>1083 cm-1>1064 cm-1。本研究拓展了 ATR-FTIR 技术在硅氧树脂材料热变性方面的研究范围。 相似文献