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1.
李贤森  项寿鹤 《催化学报》2000,21(5):475-478
探索了如何在过滤陶瓷片上制备Silicalite-l和β沸石分子筛复合膜,对它们分离水中微量苯酚和苯的性能进行了考察,并用XRD,SEM和UV等测试方法对其物理化学性能和结构进行了表征,结果表明:Silicalite-l分子筛膜,两者的平均脱除率分别为69.9%和51.5%,通过对Silicalite-l沸石分子筛复合膜进行二次合成及高温水蒸气处理,可在很大程度上改善其了性能。  相似文献   

2.
氯丙烯在不同催化剂表面上吸附的TPD结果表明:在TS-1上有三重脱附峰,而在TiO2/Silicalite上仅有单峰。H_2O_2或分子O_2在催化剂表面吸附后,在脱附物种中可用质谱检测到原子O(16)物种;说明H_O_2或分子O_2在样品表面存在解离吸附;并发现解离分子O_2的活性很低。TS-1能同时吸附氯丙烯和H_2O_2,而在SiO_2/Silicalite表面的吸附却与吸附顺序有关。环氧化活性顺序如下:TS-1(TPAOH)>TS-1(TPABr+NaOH)>TiO_2/Silicalite。TS-1沸石的高氧化活性可能与H_2O_2吸附后表面原子O(16)的形成有关。  相似文献   

3.
Fe—Silicalite—2催化剂表面CO2加氢反应性能的研究   总被引:3,自引:0,他引:3  
研究了Fe/Silicalite-2催化剂CO2加氢低碳烯烃反应性能,利用CO2-TPD,CO2/H2-TPSR和CO/H2-TPSR表征手段,考察了铁含量及MnO助剂对Fe/Silicalite-2催化剂CO2吸附脱附及加氢反应性能的影响,表明随铁含量增加可提高催化剂对CO2的吸附能力,有利于提高CO2加氢反应的转化率。  相似文献   

4.
酸处理Silicalite—Ⅰ沸石填充硅橡胶渗透蒸发分离膜   总被引:1,自引:1,他引:0  
研究酸处理Slilicalite-Ⅰ沸石对有机溶剂、水的吸附、脱附性质,酸处理Silicalite-Ⅰ填充硅橡胶对低浓度有机溶剂水溶液的渗透蒸发分离性能以及填充膜的力学性能。实验结果表明,在硅橡胶胶膜中填充酸处理Silicalite-Ⅰ沸石能改善膜对有机溶剂-水混合物的分离性能,且分离性能的改善与沸石在膜中的填充量以及硅橡胶的品种有关。另外,沸石的填充也有利于改善膜的力学性能。  相似文献   

5.
氯丙烯在不同催化剂表面上吸附的TPD结果表明在TS-1上有三重附峰,而在TiO2/Silicalite上仅有单峰,H2O2或分子O2在催化剂表面吸附后,在脱附物种中可用质谱检测到原子O(16)物种;说明H2O2或分子O2在样品表面存在解离吸附;并发现解离子分子O2的活性很低,TS-1能同时吸附内烯和H2O2,而在SiO2/Silicalite表面的吸附却与吸附顺序有关,环氧化活性顺序如下:TS-1  相似文献   

6.
研究了粒径为15μm和5μm的水热处理Silicalite-Ⅰ填充PDMS膜以及酸处理Silicalite-Ⅰ填充不同品种硅橡胶膜对低浓度乙醇-水混合物的渗透蒸发分离性能的影响。结果表明,沸石粒径的减小,不利于乙醇-水分离系数的提高;不同品种硅橡胶的沸石填充膜对乙醇-水的渗透蒸发分离性能与硅橡胶本身的性质有关。  相似文献   

7.
Silicalite-Ⅰ沸石经过酸处理或水热处理可完善其晶体结构,提高对乙醇的吸附选择性,由此提高对乙醇-水混合物的分离系数。特别是先经过酸处理再经过水热处理的Silicalite-Ⅰ沸石填充聚二甲基硅氧烷橡胶膜(PDMS橡胶膜),乙醇-水的分离系数可达30左右。  相似文献   

8.
无定型二氧化硅在硅沸石表面上的固相转化龙英才(复旦大学化学系,上海,200433)关键词硅沸石,固相转化,无定型二氧化硅硅沸石(Silicalite-1)的晶体结构与ZSM-5相同,由于其疏水/亲有机物的独特吸附特性作为一种新型沸石吸附剂有广泛的应用...  相似文献   

9.
研究水热处理Silicalite—Ⅰ沸石对乙醇和水的吸附、脱附性质以及其填充PDMS膜对乙醇、水的渗透蒸发通量和对低浓度有机溶剂一水混合物的渗透蒸发分离性能。实验结果表明,Silicalite—Ⅰ沸石经水热处理,其水吸附量大为减少,因此其填充PDMS膜对有机溶剂-水混合物,主要是醇-水混合物的分离系数有显著提高。  相似文献   

10.
研究酸处理Silicalite—I沸石对有机溶剂、水的吸附、脱附性质,酸处理Silicalite—I填充硅橡胶膜对低浓度有机溶剂水溶液的渗透蒸发分离性能以及填充膜的力学性能。实验结果表明,在硅橡胶膜中填充酸处理Silicalite—I沸石能改善膜对有机溶剂-水混合物的分离性能,且分离性能的改善与沸石在膜中的填充量以及硅橡胶的品种有关。另外,沸石的填充也有利于改善膜的力学性能。  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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