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层柱粘土材料制备与应用研究 总被引：9，自引：1，他引：9
简述了层柱粘土矿物材料研究与应用的现状和进展。利用粘土矿物蒙脱石作母体，通过大体积的铝、锆、硅等交联剂插层可制成层柱多孔材料，在酸催化、氧化还原催化中均有十分广阔的应用前景。研究表明，改进制备工艺后可提高层柱蒙脱石的热稳定性、比表面积和催化活性；通过酸或表面活性剂等预处理，再进行粘土的支撑，可以调节和控制层柱粘土的结构与性能；采用有机改性和模板导向等技术，可获得孔径介于大微孔和中孔之间的新型层柱粘土矿物材料，并应用于大分子催化反应与吸附，为粘土矿物材料合成和应用开辟了新方向。 相似文献
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由共聚法制得的铁铝复合交联剂交换钠基蒙脱石层间的水合钠离子,再经SO42-改性处理制备了铁铝复合层柱粘土固体超强酸催化剂.利用xRD、FT-IR和BET法对催化剂的结构进行了表征.以乙酸正丁酯的合成反应为探针反应对催化剂的活性进行了测试.通过正交实验确定了铁铝复合交联粘土SO42-改性最佳工艺条件.研究了催化剂对探针反应的选择性及重复使用情况.结果表明:在由实验确定的最佳改性工艺条件下,乙酸的转化率达92.2%,反应中无副产物产生,催化剂具有较好的重复使用性能. 相似文献
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以钠基蒙脱石为原料,采用共聚法合成镍铝柱化剂,利用离子交换法制备镍铝基柱撑蒙脱石。通过研究不同镍铝物质的量比例和不同NaOH的量对柱撑蒙脱石制备的影响,并对其孔道结构进行探讨。XRD结果表明,当镍铝物质的量比为1∶6、加入75mlNaOH时,可得到(001)面网层间距达1.8940nm的镍铝基柱撑蒙脱石。FT-IR显示,镍铝基聚合羟基阳离子进入蒙脱石层间,柱撑蒙脱石的基本结构并未发生改变。对柱撑前后蒙脱石的比表面积和孔径结构进行分析,发现镍铝基柱撑蒙脱石比表面积为169.68m2/g,平均孔径为4.120nm,说明镍铝基柱撑蒙脱石具有较大的比表面积,较小且均匀的孔径分布,是一种合适的催化和吸附材料。 相似文献
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柱撑粘土的晶体结构模型 总被引：5，自引：1，他引：5
根据X射线衍射、电子探针等实验数据综合分析和理论计算，讨论了柱撑基团[Al13O4(OH)24(OH2)12]^7 和[Ti20O32(OH)12(OH2)18]^4 在粘土矿物结构单元层层间的分布，铝基和钛基的笼状离子作用范围分别相当于粘土矿物的10个和6个晶胞。羧基铝柱撑蒙脱石层间孔道高度为0.9-1.2nm，直径为1.5nm；理论孔道率为84％，有效孔道率为56％。钛基柱撑蒙脱石的层间孔道高度为1.34-1.60nm，直径为1.0nm，理论也道率为75％，有效孔道率为50％。根据柱撑离子基团的两种类型，可把柱撑粘土分为Keggin型柱撑粘土和Dawson型柱撑粘土。 相似文献
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膨润土是一种以蒙脱石为主要成分的粘土类矿物。确定膨润土的属型,实质上是依据蒙脱石晶层间吸附阳离子的种类及其丰度。 (一) 蒙脱石吸附阳离子的主要原因 1.蒙脱石是属于一种2:1层状结构,即由二个硅氧四面体片夹一个铝氧八面体片构成的层状体。蒙脱石因四面体中Al~(3+)置换Si~(4+)和八面体中Mg~(2+)置换Al~(3+),使蒙脱石晶层间产生永久性负电荷,为了保持晶格电荷平衡,因而晶层间具有吸附阳离子和交换性阳离子的性能。 相似文献
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以钠化累托石为原料进行改性制备羟基锆交联累托石，并探讨以羟基锆交联累托石制备吸附有机废水的最佳条件。试验得到的最佳条件为：交联剂浓度为0．20mol／L，85℃下回流12h，累托石悬浮液浓度为60，投料比为4mmol／g时，在65℃下交联反应2．5h。在此条件下制备的羟基锆交联累托石的比表面积为9．250m^2／g，对COD的吸附容量可达119mg／L。 相似文献
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膨润土是以蒙脱石为主要成分(一般大于50%)的粘土矿物.蒙脱石属二八面体含水的层状铝硅酸盐类矿物.由于蒙脱石结构单元层中的硅和铝离子,分别被铝和镁离子置换因而层间出现电荷有吸附阳离子的作用.根据层间阳离子的不同,可分为钠基膨润土、钙基膨润土、镁基膨润土以及钙 相似文献
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利用低角度X射线衍射、红外光谱、喇曼光谱及孔结构分析,研究了用铁盐水解法制备的铁层柱蒙脱石的结构与性质。所制得的铁层柱蒙脱石以介孔型层离结构为主,微孔型柱撑结构为辅。前者为蒙脱石片层与铁离子水解产生的聚合羟基铁簇合物堆垛而成的卡房状结构,与d值为6.4±1.0nm的X射线衍射宽峰相对应;微孔型柱撑结构则与d值约1.5nm的(001)衍射峰相对应。所合成的系列铁层柱蒙脱石中最大的比表面积和孔容分别为215.7m2/g和0.291mL/g。500℃热处理后,仍保存铁层柱蒙脱石的介孔结构。铁层柱蒙脱石富含阴离子(NO3-),并作为平衡铁水解聚合物正电荷的反离子而稳定存在,可为磷钨酸离子[PW12O40]3-所交换。铁层柱蒙脱石的新型结构和特殊性质在催化剂、载体与吸附剂等领域具新的应用前景。 相似文献
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为探讨直接/间接作用模式下土壤常驻菌对蒙脱石层间距、层电荷及层间介质的影响,从绵阳地区紫色土壤中分离选取1株短小芽孢杆菌,利用透析袋,建立土壤菌与蒙脱石"接触"与"非接触"体系进行相互作用实验。作用5 d后的结果表明,蒙脱石样品层间距变小,样品M-1和M-2的d001值从1.486 nm分别减小到1.246 nm和1.257 nm,单位半晶胞层电荷数减少,且ξMMTξM-2ξM-1,FTIR分析显示作用后蒙脱石样品出现来自蛋白质酰胺Ⅱ带及蛋白质分子甲基的新特征峰,层间水分子3434 cm-1、1637 cm-1处的峰发生偏移,此外阳离子交换容量也发生明显改变。土壤菌的生物作用能改变蒙脱石的层间距、层电荷及层间介质,使其结构和性质发生改变。对比2种作用方式与作用后蒙脱石层间域特性的改变分析可知,接触作用对蒙脱石层间域特性的改变效果强于非接触作用。 相似文献
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Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
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Gilles Serge Odin 《Comptes Rendus Geoscience》2002,334(6):409-414
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414. 相似文献
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The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引：4，自引：0，他引：4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
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Emmanuel Skourtsos Daniel Vachard Alexandra Zambetakis-Lekkas Rossana Martini Louisette Zaninetti 《Comptes Rendus Geoscience》2002,334(12):925-931
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931. 相似文献
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正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.) 相似文献
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正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.) 相似文献
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正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.) 相似文献
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正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus., 相似文献
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正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an 相似文献
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正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of 相似文献