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1.
Yang  Min  Xu  Bo-qing  Liang  Juan  Sheng  Shi-shan 《催化学报》1995,(3)
氧化物-NaZSM-5催化剂的研究 Ⅰ.ZnO-NaZSM-5催化剂的表征杨民,徐柏庆,梁娟,盛世善(中国科学院大连化学物理研究所,大连116023;大连理工大学化工学院化学系,大连116012)关键词ZSM-5沸石,氧化锌,分散,强相互作用,表征在...  相似文献   

2.
杂原子Pb同晶取代Si-ZSM-12中的部分Si及其鉴定赵修松,王清遐,李宏愿(中国科学院大连化学物理研究所,大连116023)关键词Ph-ZSM-12,合成,表征ZSM-12属丝光沸石类,具有一维线性非交叉孔道(0.57×0.61nm)[1,2],...  相似文献   

3.
合成C_2含氧化物的Rh-Mn-Li/SiO_2催化剂的优化研究   总被引:1,自引:0,他引:1  
合成C_2含氧化物的Rh-Mn-Li/SiO_2催化剂的优化研究罗洪原,谢水波,林励吾,梁东白(中国科学院大连化学物理研究所,大连116023)关键词合成气,C_2含氧化物,铑催化剂,锰,锂CO加氢合成C_2含氧化合物由于具有较高的收率、较好的产品价格及...  相似文献   

4.
担载型Fe_2O_3/ACDM催化剂用于甲醇转化反应的研究夏清华,陈国权,王清遐,王公慰(中国科学院大连化学物理研究所大连116012)关键词ZSM-5沸石,铁浸渍改性,甲醇转化,低碳烯烃,酸性在煤基甲醇制低碳烯烃的MTO过程的研究中,通常是对ZSM...  相似文献   

5.
分子筛催化剂的失活与积炭   总被引:9,自引:0,他引:9  
分子筛催化剂的失活与积炭刘中民,陈国权,王清遐,梁娟,蔡光宇(中国科学院大连化学物理研究所,大连116023)关键词分子筛,结炭,催化剂失活,甲醇转化,HZSM-5结炭是酸性分子筛催化剂失活的主要因素.本文通过具有碳链增长、环化、烷基化等多种反应途径...  相似文献   

6.
催化新材料γ-Mo_2N的合成张耀军,魏昭彬,李新生,辛勤(中国科学院大连化学物理研究所催化基础国家重点实验室大连116023)高比表面氮化钼是一种有应用潜力的催化新材料,对于烃类脱氢、氢解、异构化及加氢脱氮、加氢脱硫等反应具有优良的催化性能 ̄[1-...  相似文献   

7.
Cu(Ⅱ)与L-氨基酸和5'-嘌呤核苷酸配合物的SOD活性   总被引:1,自引:0,他引:1  
Cu(Ⅱ)与L-氨基酸和5'-嘌呤核苷酸配合物的SOD活性邵昌平,赵丽华,刘宇新,郭和夫(中国科学院大连化学物理研究所,大连116023)关键词Cu(Ⅱ)-氨基酸配合物,Cu(Ⅱ)-氨基酸-核苷酸配合物,SOD活性.1.前言在已发现的三种超氧化物歧化...  相似文献   

8.
乙醇对合成醇用Cu-Co-Fe催化剂的修饰效应   总被引:2,自引:0,他引:2  
徐杰  王向宇  杜宝石  辛勤  李灿 《催化学报》1998,19(3):264-267
乙醇对合成醇用Cu┐Co┐Fe催化剂的修饰效应徐杰王向宇杜宝石(郑州大学化学系,郑州450052)辛勤李灿(中国科学院大连化学物理研究所,大连116023)关键词铜,钴,铁,合成醇,乙醇,修饰作用分类号O643/O647自70年代以来,已对多种CO加...  相似文献   

9.
α-β不饱和醛中C=C和C=O键选择加氢的研究进展   总被引:3,自引:0,他引:3  
杨树武  徐江  辛勤 《分子催化》1998,12(2):152-160
α-β不饱和醛中C=C和C=O键选择加氢的研究进展杨树武徐江辛勤1)(中国科学院大连化学物理研究所催化基础国家重点实验室大连116023)关键词α-β不饱和醛选择加氢贵金属催化剂分类号O643.32随着催化学科的发展,控制反应的选择性变得越来越重要,...  相似文献   

10.
Co-B非晶态合金超细微粒催化剂的研究   总被引:1,自引:0,他引:1  
Co-B非晶态合金超细微粒催化剂的研究姚凯文,范以宁,陈懿,李新生(南京大学化学系,南京210093;中国科学院大连化学物理研究所催化基础国家重点实验室,大连116023)关键词非晶态,超细微粒,钴基合金,硼合金,一氧化碳,加氢非晶态合金超细微粒兼有...  相似文献   

11.
《Supramolecular Science》1998,5(5-6):553-558
Effect of trivalent elements on the thermal and hydrothermal stability of MCM-41 mesoporous molecular sieve materials has been investigated. Al(III) decreases the thermal and hydrothermal stability of MCM-41 materials, whereas La(III) and Fe(III), especially Fe(III), can improve the thermal and hydrothermal stability. Benzene adsorption and IR spectra suggested that thick channel wall and the fewer structural defect sites in MCM-41 would enhance the thermal and hydrothermal stability of MCM-41.  相似文献   

12.
In this study, nanoscale MCM-41 molecular sieve was prepared under a basic condition by a hydrothermal method using cetyltrimethylammonium bromide as a template and tetraethyl orthosilicate as a silica source. Methylated nanoscale MCM-41 molecular sieve was prepared from the nanoscale MCM-41 by post-synthesis method using trimethylchlorosilane (TMCS) as coupling agent. The product was characterized by means of element analysis, powder X-ray diffraction, Fourier transform infrared (FT-IR) spectroscopy, low-temperature nitrogen adsorption-desorption technique at 77 K, scanning electron microscopic (SEM), thermogravimetry-differential thermal analysis (TG-DTA). Powder XRD showed that the framework of the molecular sieve was well retained and the degree of ordering of the methylated MCM-41 decreases. IR spectra and the low-temperature nitrogen adsorption-desorption technique suggested that methyl was successfully grafted to the inner surface of the methylated MCM-41 and the mesoporous channels of the methylated MCM-41 were still maintained. Scanning electron microscopic results showed that the average size of the methylated MCM-41 prepared was 112 nm. Differential thermal analysis showed that the prepared material has preferable thermal stability and the methylated MCM-41 can be stable at 903 °C.  相似文献   

13.
An enzyme, horseradish peroxidase (HRP), was adsorbed in the manner of single immersion method on the silica mesoporous materials, FSM-16, MCM-41 and SBA-15 with various pore diameters from 27 to 92 and their enzymatic activity in an organic solvent and the thermal stability were studied. FSM-16 and MCM-41 showed larger amount of adsorption of HRP than SBA-15 or silica gel,when the pore sizes were larger than the spherical molecular diameter of HRP (ca 64×37). The increased enzyme adsorption capacity may be due to the surface characteristics of FSM-16 and MCM-41, which would be consistent with the observed larger adsorption capacity of cationic pigment compared with anionic pigment for these materials. The immobilized HRP on FSM-16 and MCM-41 with pore diameter above 50 showed the highest enzymatic activity in an organic toluene and thermal stability in aqueous solution at the temperature of 70℃. The immobilized enzymes on the other mesoporous materials including large or small pore sized FSM-16 showed lower enzymatic activity in an organic solvent and the thermal stability. Both surface character and size matching between pore sizes and the molecular diameters of HRP were important in achieving high enzymatic activity in organic solvent and high thermal stability.  相似文献   

14.
以碱处理的ZSM-5浆液为硅铝源,通过水热自组装过程合成了介孔-微孔复合孔道结构的分子筛,并采用XRD、BET、HRTEM、Py-IR和水热处理等手段对合成分子筛进行了表征。结果表明,碱处理ZSM-5时的苛刻程度是影响复合分子筛合成的重要因素,适宜的碱处理条件为NaOH浓度1 mol/L、80℃时处理1 h。表征结果表明,复合分子筛具有规整互通的微孔-介孔梯级复合孔道结构,孔容、比表面积和平均孔径分别为0.63 mL/g,684 m2/g和3.76 nm,属典型的MCM-41结构;与MCM-41相比,复合分子筛的B酸(尤其是强B酸)酸量明显增强,水热稳定性显著提高。  相似文献   

15.
 利用直接合成法和后接枝法将含有磺酸基团的硅烷偶联剂引入MCM-41介孔分子筛中, 合成了酸性介孔有机-无机杂化材料. 利用XRD和TEM等方法对其结构进行了表征. 结果表明,利用直接合成法和后接枝法合成的杂化材料仍保持规整的介孔孔道,该材料作为酸催化剂在苯甲醛与乙二醇的缩醛反应中显示了较好的催化活性.  相似文献   

16.
以十六烷基三甲基溴化铵为模板剂,硅酸钠为硅源,铝酸钠为铝源,在水热条件下成功地合成出了MCM-41中孔硅酸盐材料。采用XRD、低温N2吸附脱附等测试手段对合成的MCM-41样品进行了表征。通过优化合成条件,合成出孔径3.2 nm、比表面904m2/g和孔壁厚约1.46 nm的MCM-41分子筛。催化活性测定采用微反应活性实验来评价其活性和选择性。  相似文献   

17.
Rapid synthesis of highly ordered Si-MCM-41   总被引:2,自引:0,他引:2  
A very short-time synthesis of highly ordered MCM-41 molecular sieve was formulated by using cetyltrimethylammonium bromide (CTAB) as the template and silica gel from SiliCycle as the silica source. The physical properties of MCM-41 samples were characterized by X-ray diffraction (XRD), nitrogen physisorption, and transmission electron microscopy (TEM). The MCM-41 sample prepared in this study exhibited well defined long-range order and good hydrothermal stability. It was demonstrated that reducing the time of self-assembly step to 2 h during the synthesis had no unfavorable effect on the quality of MCM-41 materials.  相似文献   

18.
丝光沸石前驱体组装MCM-41介孔分子筛   总被引:1,自引:2,他引:1  
MCM-41分子筛是具有单一孔径的长程有序介孔材料,由于孔壁是无定形结构,与微孔沸石晶体相比,水热稳定性较差,这使其在石油炼制和精细化工中的应用受到很大的限制.根据实验发现,如果将一些沸石的前驱结构单元体--即在形成完整的沸石结构前所形成的初级或次级结构单元引入介孔材料,使其转化为介孔孔壁,将会增加介孔材料的短程有序化程度,提高水热稳定性.  相似文献   

19.
以十六烷基三甲基溴化铵为模板剂,以具有Y沸石次级结构单元的水凝胶为前驱体,在pH=10左右的条件下合成了与MCM-41相类似的介孔分子筛。同时利用各种表征手段对合成的样品进行了一系列的表征。结果表明,所合成的样品具有六方规整结构和较厚的孔壁,并具有较强酸强度和水热稳定性。同时,考察了其负载Pd-Pt活性组分后的萘加氢反应活性和抗硫性,并与常规法合成的具有相同硅铝比的MCM-41载体进行了比较。  相似文献   

20.
Surface modification offers a great opportunity to adjust both the pore diameter and surface properties of MCM-41 type organic–inorganic hybrid materials which result in materials of improved hydrothermal and mechanical stability. Therefore, MCM-41 silica, surface modified with organic ligands, are promising systems with engineered properties and attractive for advanced applications. In the present study, after optimization of the reaction conditions highly ordered MCM-41 silica spheres with uniform mesopores were prepared by the pseudomorphic transformation route. The effect of functionality and alkyl chain length of the alkyl ligands during surface modification was probed by using butyl and octylsilanes with two different functionalities. Due to steric hindrance, the longer chains are assumed to bind only on the outer silica surface and near the entrance of the pores, while the shorter chains are also able to bind to the interior mesopore walls. The resulting materials were comprehensively characterized before and after surface modification using nitrogen sorption techniques, XRD, SEM, solid-state NMR spectroscopy and FTIR spectroscopy. From chromatographic test measurements it was found that the separation power primarily depends on surface coverage and alkyl chain length. On the basis of the present data, surface modified mesoporous silica of MCM-41 type are very promising candidates for future chromatographic applications.  相似文献   

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