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91.
Orlik S. N. Ostapyuk V. A. Alekseenko L. M. 《Theoretical and Experimental Chemistry》2002,38(3):195-198
The possibility of making products of partial oxidation, alcohols and acids in particular, by the reaction of C3-C4 alkanes with nitrogen monoxide over oxide and zeolite catalysts is demonstrated. The most effective catalysts are CeO2 and Fe-TsVK. The dependence of the rate and selectivity of the process on the reaction conditions has been established. 相似文献
92.
碱金属沸石上乙醇双分子缩合反应及其机理 总被引:1,自引:0,他引:1
首次发现在碱金属X沸石上乙醇能够发生以正丁醇为主产物的双分子缩合反应,在所研究的催化剂中,含Rb的LiX沸石表现出较高的反应活性和选择性。反应机理的研究表明,反应不经过aldol缩合步骤。在此基础上,对反应机理提出了新建议:在碱性沸石作用下,乙醇的β-位C-H键被活化,双分子脱水导致缩合。碳链的增长按此模式进行。 相似文献
93.
94.
95.
Summary The pozzolanic reactivity of thermally treated zeolites was studied on the basis of the Chapelle test combined with X-ray
diffraction (XRD) and Fourier Transform (FTIR) spectroscopy, as well as thermogravimetric analysis (TG/DTG) and differential
thermal analysis (DTA). The raw zeolite samples are from the Pentalofos area, Thrace, NE Greece. Their main mineral constituent
is 'heulandite type-II', an intermediate type of the heulandite-clinoptilolite isomorphous series. Calcination of the samples
was carried out up to 400, 500, 600, 700 and 1000°C for 15 h. The changes were recorded using the above methods. The deformation
of the zeolite crystal lattice starts at about 400°C and proceeds as the temperature of thermal treatment rises. The thermal
treatment of zeolite at 400°C improves its pozzolanic reactivity and accelerates the reaction with Ca(OH)2. 相似文献
96.
97.
Jie Bai Shenglin Liu Sujuan Xie Longya Xu Liwu Lin 《Reaction Kinetics and Catalysis Letters》2004,82(2):279-286
A comparison of methane dehydroaromatization (MDA) on 6Mo/MCM-22 and 6Mo/ZSM-5 was carried out using a gas mixture of 90%CH4, 2%CO2 and 8%Ar as the feed. The results indicate that the stability of 6Mo/MCM-22 is better than that of 6Mo/ZSM-5. A detailed
study reveals that the ability for coke accommodation and the retention of the shape selectivity for aromatics formation is
responsible for the stability of a MDA catalyst.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
98.
M. A. Grzegozek 《Chemistry of Heterocyclic Compounds》2002,38(6):692-694
The intermediate -adducts of chloromethyl phenyl sulfone with 3-nitro-, 5-nitro-, 6-nitro-, 7-nitro- and 8-nitroquinoline are detected by 1H NMR spectroscopy. 相似文献
99.
高硅沸石骨架结构及其稳定性的模拟计算(I)* 总被引:2,自引:0,他引:2
The lattice energy of a series of high-silica zeolites was determined using the lattice energy minimization method. The results were compared to the lattice energy of dense polymorphs of SiO2. All high-silica zeolites frameworks are only 30~67kJ•mol-1 less stable than α-quartz This may imply that there is little energy barrier to the formation of high-silica zeolites frame-works and explain the structural diversity observed for high-silica zeolites. The relationships of calculated lattice energies and framework Structures was disscussed. The results revealed a good linear relationship between framework density of these molecular sieves and all-silica framework lattice energies. 相似文献
100.