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使用不同方法合成了MCM-41,制备出具有不同骨架结构和内部孔道结构的介孔分子筛。通过XRD、高倍投射电镜、低温氮吸附/脱附等方法对样品进行了表征分析。用PEI对MCM-41分子筛进行改性,然后使用热重方法测定了其对CO2的吸附量。结果表明,使用硅酸钠和硫酸为原料制备的样品具有较大的比表面积和孔容,在该样品上负载50%PEI吸附量达到了269.3 mg/g,是同等条件下单纯PEI吸附量的3.4倍。说明将PEI负载在具有大比表面积和孔容的MCM-41介孔分子筛上,可以使PEI得到充分分散,并充分利用PEI分子上的氨基。 相似文献
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以煅烧的分子筛SBA-15为主体材料,二溴对氯偶氮胂(dibromochloro-arsenazo,DBC-ASA)作客体材料,以水为介质,用液相移植法制备了(SBA-15)-(DBC-ASA)主客体复合材料.用粉末X射线衍射、Fourier变换红外光谱、固体扩散漫反射吸收光谱及发光研究表征了所制得的复合材料(SBA-15)-(DBC-ASA)的性质.X射线衍射结果表明:(SBA-15)-(DBC-ASA)主客体复合材料分子筛骨架存在且有序度高.红外光谱分析表明:较低量的DBC-ASA引入SBA-15分子筛中,分子筛骨架结构仍然存在,但引入量较大时,分子筛的骨架有序度明显降低.固体扩散漫反射吸收光谱研究表明:DBC-ASA处于分子筛SBA-15孔道内,分子筛孔道对DBC-ASA具有立体限域效应.发光光谱分析表明:所制得的样品的非辐射过程强,导致电子-光子作用极强,产生电荷迁移和跃迁,发生Stokes位移,光谱谱带变宽. 相似文献
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文章以FeCl3为氧化剂,采用原位化学聚合的方法制备了聚噻吩/MCM-41新型复合材料,并对其结构和性能进行了表征。结果表明:小角X射线衍射和氮气吸附与脱附说明复合材料具有规则的介孔结构并且孔径明显小于分子筛MCM-41的孔径,红外光谱分析进一步证明PT进入了MCM-41的介孔孔道内,热重分析表明,聚噻吩进入孔道之后热稳定性得到了提高。 相似文献
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采用液体-固体-溶液界面相转移和相分离法(LSS)制备单分散CdS量子点(CdS-QDs);通过自由基本体聚合合成单分散CdS量子点/聚苯乙烯(CdS/PSt)纳米复合材料,采用HRTEM、XRD、FTIR、PL对CdS纳米晶、CdS/PSt复合材料的微观结构、形貌、化学组成、光学性能进行了表征。结果表明:CdS纳米晶为单分散,粒径约为4nm;所制备的CdS/PSt纳米复合材料具有优越的荧光性能及荧光稳定性,其聚合物中的CdS纳米晶仍然保持很好的量子尺寸效应和良好的分散性。 相似文献
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表面活性剂采用十六烷基三甲基溴化铵为活性成分,硅源采用正硅酸乙酯,利用低温水热法合成了MCM-4l介孔分子筛,采用动态吸附法将阿司匹林药物吸附到分子筛MCM-41的孔道中,吸附前后的介孔分子筛分别利用傅里叶红外光谱(IR)、紫外光谱(UV)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)等对吸附前后的分子筛进行了表征;借助紫外-可见吸收光谱(UV)研究了分子筛的最大吸附量、吸附时间、体外释放等。结果显示,所合成的分子筛MCM-41有序的介孔材料;MCM-4l用于药物阿司匹林的载体最大载药量为:45mg·g-1(m(药物)/m(载体))和良好的缓释效果。 相似文献
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Somayyeh Kalami Hamid Reza Aghabozorg Behdad Ghaderi Ashtiani 《Journal of Porous Materials》2013,20(4):821-826
In the present study, preparation, characterization and catalytic activity of encapsulated copper (II) complexes within MCM-41 were investigated. The mesoporous molecular sieve MCM-41 was synthesized and grafted with 3-(trimethoxysilyl)-1-propanethiol to give a thiol modified material (MCM-41-S). The prepared material successively was reacted with acrylic acid and acrylonitrile to give AA-MCM-41 and AN-MCM-41, respectively. Using hexamethyldisilazane and copper (II) chloride, copper (II) complexes in the cavities of MCM-41 (Cu-AA-MCM-41 and Cu-AN-MCM-41) were prepared. The presence of copper (II) complex on the surfaces of host matrix and the structure of prepared catalyst is investigated by FT-IR, inductively coupled plasma-optical emission spectroscopy (ICP-OES), powder X-ray diffraction (XRD) and BET nitrogen adsorption–desorption methods. The catalytic activities of the catalysts were studied in epoxidation of olefins. The results showed that activities of the prepared catalysts (Cu-AA-MCM-41 and Cu-AN-MCM-41) and their selectivity to corresponding epoxides were more than those of MCM-41. In addition, the synthesized heterogeneous catalysts were truly reusable. 相似文献
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以丝光沸石分子筛为硅铝源,通过碱液处理和表面活性剂的自组装作用,水热条件下合成了MOR/MCM-41复合分子筛。通过XRD、SEM、TEM、N2吸附/脱附和水热稳定性处理等手段对合成的复合材料进行了表征。结果表明,复合材料不仅保留了原丝光沸石晶体的规则形貌,同时兼具微孔分子筛MOR和介孔分子筛MCM-41的特征,且介孔(20~30 nm)在微孔分子筛中较均匀地分布。水热处理测试结果表明,MOR/MCM-41复合分子筛具有较高的水热稳定性,水热处理100 h后介孔结构依然存在。 相似文献
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A novel solid support adsorbent for CO2 capture was developed by loading pentaethylenehexamine (PEHA) on commercial y available mesoporous molecular sieve MCM-41 using wet impregnation method. MCM-41 sam-ples before and after PEHA loading were characterized by X-ray powder diffraction, N2 adsorption/desorption, thermal gravimetric analysis and scanning electron microscope to investigate the textural and thermo-physical properties. CO2 adsorption performance was evaluated in a fixed bed adsorption system. Results indicated that the structure of MCM-41 was preserved after loading PEHA. Surface area and total pore volume of PEHA loaded MCM-41 decreased with the increase of loading. The working adsorption capacity of CO2 could be significantly improved at 60%of PEHA loading and 75 °C. The effect of the height of adsorbent bed was investigated and the best working adsorption capacity for MCM-41-PEHA-60 reached 165 mg·(g adsorbent)?1 at 75 °C. Adsorption/desorption circle showed that the CO2 working adsorption capacity of MCM-41-PEHA kept stable. ? 2014 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. Al rights reserved. 相似文献
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以氢氧化钠溶液处理微孔沸石ZSM-5来提供硅铝源,合成了ZSM-5/MCM-41复合结构型分子筛。采用XRD、N2吸附脱附、TEM等方法对其进行了表征,考察了其水热稳定性。实验结果表明,碱处理合成的ZSM-5/MCM-41同时具有微孔孔道和介孔孔道结构,并具有优于介孔MCM-41分子筛的水热稳定性。以ZSM-5/MCM-41为载体负载三氧化钨后应用于噻吩/正辛烷模拟油体系,双氧水为氧化剂,催化氧化脱硫,WO3-ZSM-5/MCM-41(三氧化钨质量分数为10%)表现出良好的催化性能,脱硫率可达到93.6%。 相似文献
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按n(SiO2)∶n(Na2O)∶n(Al2O3)∶n(H2O)=1∶1.5∶0.5∶100加料,在90℃下水热晶化3 h合成NaA微孔分子筛,再按n(SiO2)∶n(NaOH)∶n(CTAB)∶n(H2O)=1∶0.3∶0.3∶90依次添加到NaA微孔分子筛中,于110℃下水热晶化24 h合成NaA/MCM-41微介复合分子筛,并采用XRD、SEM(EDS)和TEM等方法对其进行了表征。吸附阳离子红X-5GN模拟染料废水结果表明,在50 mLρ(阳离子红X-5GN)=20 mg/L的水溶液中,NaA/MCM-41微介复合分子筛的投加量为0.6 g/L、pH=6、振荡时间为60 min时,脱色率可达到96.4%,比NaA分子筛和MCM-41介孔分子筛独自吸附脱色效果要好。 相似文献
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本文以十六烷基三甲基溴化铵(CTAB)为模板剂、正硅酸乙酯(TEOS)为无机硅源以及1,3,5-三甲苯(TMB)为加长剂合成了有序介孔分子筛(MCM-41)。选择Eu(DBM)3phen为客体,纳米级介孔分子筛为主体,在氯仿中进行分子组装,制备具有强发光性能的超分子纳米复合材料Eu(DBM)3phen/APTES-MCM-41。采用XRD、HRTEM和荧光光谱分析等对产物的结构与性能进行了分析。结果表明,Eu(DBM)3phen组装进APTES-MCM-41孔道之后,发光纯度提高。其原因为APTES-MCM-41表面的-NH2基团强烈影响了Eu3 离子周围的配位场。由于配位场的微扰作用,Eu(DBM)3phen配合物的对称性强烈下降,导致发光纯度提高。结果同时表明,Eu(DBM)3phen/APTES-MCM-41随着Eu3 离子组装量的增加而发光强度提高。 相似文献
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以正硅酸乙酯为硅源、十六烷基三甲基溴化铵为模板,在氟化物存在的条件下,通过水热法在不同晶化温度和时间下进行复合分子筛Y/MCM-48的合成。利用X射线粉末衍射、Fourier变换红外光谱、N2吸附–脱附、扫描电子显微镜和透射电子显微镜对合成的样品进行表征,同时考察了样品的稳定性及不同晶化时间和温度下样品的晶相。结果表明:在120℃水热晶化36h合成的Y/MCM-48具有良好有序的MCM-48介孔相以及NaY微孔相的双重孔结构,其比表面积高达864 m2/g,平均孔径为2.4 nm。样品经800℃焙烧4 h、100℃水热处理48 h后,复合分子筛的双重孔结构仍然存在。 相似文献
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Copper incorporated MCM-48 molecular sieve adsorbents with different Cu content have been hydrothermally synthesized. The samples have been characterized by various physicochemical methods, including X-ray diffraction (XRD), nitrogen adsorption (N2) and X-ray photoelectron spectroscopy (XPS). The results reveal that Cu-MCM-48 with mass fraction of copper up to 10 % can still retain the uniform mesoporous framework of MCM-48. The copper in the framework of MCM-48 was easily auto-reduced to Cu(I) in N2 at high temperature, which did not alter the mesoporous structure of MCM-48. The adsorption equilibrium isotherms of ethylene and ethane on these molecular sieve adsorbents have been measured at 30℃. At 100 kPa, the adsorption capacities of ethylene on 5Cu-MCM-48 and 10Cu-MCM-48 are higher than those on MCM-48. The 10Cu-MCM-48 molecular sieve adsorbent has a higher selective adsorption ratio of ethylene to ethane, the separation factor is 3.8, and the amount of ethylene adsorbed is 11.1 ml·g ^-1. 相似文献