Zeolites最新文献_第7页

Synthesis and characterisation of transition-metal-substituted gallium phosphates with the laumontite structure 具有湖沸石结构的过渡金属取代磷酸镓的合成与表征

Zeolites Pub Date : 1997-11-01 DOI: 10.1016/S0144-2449(97)00099-7

Andrew D. Bond, Ann M. Chippindale , Andrew R. Cowley, Jennifer E. Readman, Anthony V. Powell

引用次数: 25

Location of Brønsted sites in mordenite 丝光沸石中Brønsted遗址的位置

Zeolites Pub Date : 1997-11-01 DOI: 10.1016/S0144-2449(97)00114-0

Alberto Alberti

引用次数: 79

Diffuse reflectance i.r. spectroscopic study on hydroxyl groups of H-ZSM-5s having different sizes and properties h - zsm -5不同尺寸和性质羟基的漫反射红外光谱研究

Zeolites Pub Date : 1997-11-01 DOI: 10.1016/S0144-2449(97)00112-7

Shu-Bin Pu, Tomoyuki Inui

引用次数: 19

Solid-state ion exchange in zeolites: Part 8. Interaction of lanthanum(III) chloride with zeolites under anhydrous conditions 沸石中的固态离子交换:第8部分。无水条件下氯化镧与沸石的相互作用

Zeolites Pub Date : 1997-11-01 DOI: 10.1016/S0144-2449(97)00118-8

Bogdan Sulikowski , Josef Find, Hellmut G. Karge, Daniel Herein

引用次数: 24

Synthesis, characterization, and catalytic properties of a novel Germano-aluminophosphate molecular sieve with AEL structure: GeAPO-11 具有AEL结构的新型锗-磷酸铝分子筛:GeAPO-11的合成、表征及催化性能

Zeolites Pub Date : 1997-11-01 DOI: 10.1016/S0144-2449(97)00082-1

P. Mériaudeau, Vu A. Tuan, Le N. Hung, G. Szabo

引用次数: 3

States of aluminum in zeolite β and influence of acidic or basic medium 铝在β沸石中的状态及酸性或碱性介质的影响

Zeolites Pub Date : 1997-11-01 DOI: 10.1016/S0144-2449(97)00103-6

Chun Yang, Qinhua Xuaf

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引用次数: 71

Mutinaite, a new zeolite from Antarctica: The natural counterpart of ZSM-5 Mutinaite，一种来自南极洲的新型沸石:ZSM-5的天然对应物

Zeolites Pub Date : 1997-11-01 DOI: 10.1016/S0144-2449(97)00100-0

Ermanno Galli, Giovanna Vezzalini, Simona Quartieri, Alberto Alberti, Marco Franzini

{"title":"Mutinaite, a new zeolite from Antarctica: The natural counterpart of ZSM-5","authors":"Ermanno Galli, Giovanna Vezzalini, Simona Quartieri, Alberto Alberti, Marco Franzini","doi":"10.1016/S0144-2449(97)00100-0","DOIUrl":"10.1016/S0144-2449(97)00100-0","url":null,"abstract":"<div>Mutinaite is the third new zeolite from Ferrar dolerites at Mt. Adamson (Northern Victoria Land, Antarctica). The mineral occurs as subspherical aggregates of tiny radiating lath-like fibres or as aggregates of transparent, colourless to pale-milky, tiny tabular crystals; it has vitreous luster, white streak and good 100 cleavage. Mutinaite is brittle with dmeas = 2.14(3) and dcalc = 2.17 g/cm3. Optically, it is biaxial negative with α = 1.485(2), β = 1.487(2) and γ = 1.488(2). The orientation is X = b, Y = a, Z = c. Mutinaite is orthorhombic with a = 20.223(7), b = 20.052(8), c = 13.491 (5)Å, space group Pnma. The strongest powder X-ray diffraction lines are (d(Å), I, hkl): 11.20, 84, 101, 011; 9.98, 35, 200,020; 3.85, 100, 501, 051; 3.75, 98, 303; 3.67, 27, 133; 3.00, 32, 503. The framework topology is that of the synthetic zeolite ZSM-5. The chemical formula is: (Na2.76K0.11Mg0.21Ca3.78)Σ = 6.86(Al11.20Si84.91)Σ=96.11O192 · 60H2O. The Si/Al ratio, equal to 7.6, is the highest found in a natural zeolite. Thermal stability and rehydration capacity are very high. The name is from Mutina, the ancient Latin name of the city of Modena.</div>","PeriodicalId":23983,"journal":{"name":"Zeolites","volume":"19 5","pages":"Pages 318-322"},"PeriodicalIF":0.0,"publicationDate":"1997-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0144-2449(97)00100-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88403322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 35

Alkylation of toluene on HSAPO-5 with various Si concentrations 甲苯在不同硅浓度的HSAPO-5上的烷基化反应

Zeolites Pub Date : 1997-11-01 DOI: 10.1016/S0144-2449(97)00116-4

T. Masukawa, T. Komatsu, T. Yashima

{"title":"Alkylation of toluene on HSAPO-5 with various Si concentrations","authors":"T. Masukawa, T. Komatsu, T. Yashima","doi":"10.1016/S0144-2449(97)00116-4","DOIUrl":"10.1016/S0144-2449(97)00116-4","url":null,"abstract":"<div>HSAPO-5 with various Si concentrations was used as a catalyst for the alkylation of toluene with methanol to investigate weak acid sites. On HSAPO-5 with Si/(Al + P + Si) ≦ 0.026, the conversion of toluene increased with time on stream for a certain period, whereas the conversion decreased monotonously on HSAPO-5 with higher Si concentrations. Pretreatment with methanol on HSAPO-5 with Si/(Al + P + Si) = 0.018 increased the initial conversion of toluene. From the measurement of the amount of coke deposited on HSAPO-5, it is suggested that during the initial stage of the reaction coke is mainly produced by the reaction of methanol by itself at the acid sites on the external surface of HSAPO-5 with low Si concentrations. A small amount of coke thus formed would gradually retard the further self-conversion of methanol into coke. Therefore, the fraction of methanol used for the alkylation could increase, resulting in the increase in toluene conversion. It is suggested that the acid sites on the external surface are stronger than those formed by the substitution of Si for P but are weaker than those formed in aluminosilicate regions existing in HSAPO-5 with high Si concentrations.</div>","PeriodicalId":23983,"journal":{"name":"Zeolites","volume":"19 5","pages":"Pages 429-433"},"PeriodicalIF":0.0,"publicationDate":"1997-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0144-2449(97)00116-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76089309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Coordination state of gallium in MFI structures prepared by direct synthesis and by postsynthetic modification of boralites 硼钛矿直接合成及合成后修饰制备的MFI结构中镓的配位态

Zeolites Pub Date : 1997-11-01 DOI: 10.1016/S0144-2449(97)00089-4

Richard Klik, Vladimír Bosáček, Ludmila Kubelková, Dieter Freude, Dieter Michel

引用次数: 10

Zeolite cycle sequences 沸石循环序列

Zeolites Pub Date : 1997-11-01 DOI: 10.1016/S0144-2449(97)00122-X

G. Thimm, W.E. Klee

引用次数: 9