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中孔分子筛SO42-/Zr-MCM-41催化裂解聚丙烯反应研究  [PDF]
刘福胜,雷火星,解从霞,于世涛,谢芳菲,葛晓萍
分子催化 , 2007,
Abstract: 采用水热合成法制备了不同硅锆比的中孔分子筛Zr-MCM-41,用强酸性基团SO42-对其进行修饰,制得SO42-/Zr-MCM-41中孔分子筛.采用XRD、FT-IR、NH3-TPD及氮气吸附脱附等技术对其结构和酸强度进行表征.通过改变硅锆比、负载不同的酸性基团对Zr-MCM-41的酸性进行调变,并将其用于催化聚丙烯(PP)的裂解反应,结果表明S i/Zr=40的SO42-/Zr-MCM-41具有较好的催化裂解活性.另外,与热裂解以及HZSM-5和Zr-MCM-41为催化剂时PP的裂解反应结果进行了比较,结果证明SO42-/Zr-MCM-41不仅具有较高的裂解转化率,而且具有较高的液体产物收率,适宜于空间位阻较大的PP的催化裂解反应.
Immobilization of Lipase from Candida rugosa on Mesoporous MCM 41  [PDF]
Roberto Rodrigues de Souza, Renata D. M. Ferreira
Journal of Biosciences and Medicines (JBM) , 2014, DOI: 10.4236/jbm.2014.24011
Abstract:

The use of enzymatic route for production of biofuels is growing up due the mild reaction conditions that this method provides, as well as reducing SOx emission. To reduce costs, it’s necessary to immobilize the enzyme, making possible to use it continuously as biocatalyst. The aim of this work was to measure the influence of the mass of support and pH used for immobilization of commercial lipase from Candida rugosa acquired by Sigma laboratory. The immobilization method chosen was adsorption on mesoporous and hydrophobic support MCM 41, this has been treated with nitric acid 10% v/v to remove any organic residue. Then, 20 ml of enzymatic solution in phosphate buffer (pH 6.0, 7.0 and 8.0; 50 mM) and 1 g/L was placed under constant stirring with 0.30 and 0.45 g of support. Aliquots were taken from the reaction medium and analyzed by spectrophotometry at 10 minutes intervals. A volume of 0.2 ml of supernatant was put with 1.8 ml of substrate p-NFL at 0.18 g/L, and the absorbance at 410 nm was analyzed. In four cases there was a sharp reduction of supernatant’s activity at first 10 minutes, that ratifies the big affinity of the enzyme for the support and the negative influence of pH about the activity. Using the calibration curve, it was possible to calculate the final activity of each immobilization batch. This work suggests the occurrence of diffusional effects, which means that the enzyme mobility was restricted due the excessive amount of support, and then, it lost a part of accessibility to substrate, reflecting in not expressive activity values, and changing the state of ionization of the components of the system.

MoO3在介孔分子筛MCM―41上分散状况的研究  [PDF]
郭锐,马骏
分子催化 , 2001,
Abstract: 采用XPS和XRD方法,测定了MoO3在未经改性的MCM-41及用Al2O3和TiO2改性后的MCM-41上的单层分散阈值,发现,MoO3在用Al2O3和TiO2改性后的MCM-41上的单层分散阈值比未经改性的MCM-41上的要提高三分之二。另外,借助MoO3/MCM-41、MoO3/Al2O3-MCM-41、MoO3/TiO2-MCM-41系列样品的比表面积和孔分布测定,研究了MoO3在未经改性的MCM-41及用Al2O3和TiO2改性后的MCM-41上的分散状况。
Synthesis of MCM–41 mesoporous molecular sieves containing heteroatoms and their catalytic activity

ZHOU Huafeng YANG Yongjin,ZHANG Jinsong,

材料研究学报 , 2009,
Abstract: MCM–41 mesoporous molecular sieves containing heteroatoms (Zn, Ni, Fe, Al, Cu, Ce) (T–MCM–41) were synthesized by direct hydrothermal process and were applied in the synthesis of dioctyl phthalate (DOP) in this paper. The effects of different heteroatoms incorporation on structure, specific surface area and pore volume, aciditity and catalytic activity of T–MCM–41 were investigated. The results show that T–MCM–41 which still remains the well–ordered hexagonal mesostructure of MCM–41 has high surface area (550–900 m2/g), large pore diameter (~3 nm). Meanwhile, it has high catalytic activity and selectivity in DOP synthesis because heteroatoms incorporation can produce acid centers. When T–MCM– 41 (T=Zn, Fe, Al, Cu) is used as the catalyst, the conversion of phthalic anhydride (PA) reaches above 95.5% and DOP selectivity reaches above 96.5% in 5 h. Moreover, T–MCM–41 has good stability and Al–MCM–41 holds good catalytic activity after being reused five times.
Physicochemical Properties of CuO2 (acac)2 Supported on Functionalized MCM41 Containing Thiourea Ligand  [PDF]
Amirah Ahmad,Hamizah Md. Rasid,Karimah Kassim
International Journal of Chemical Engineering and Applications , 2013, DOI: 10.7763/ijcea.2013.v4.249
Abstract: A new material is prepared by encapsulating functionalized-MCM41 with 2-hydroxy-2-mercaptopyrimidine (2-thiouracil) and copper acetate monohydrate. The functionalized-MCM41 was first synthesized by using Ludox as silica source and cetyltrimethylammonium bromide (CTABr) as template and was modified via co-condensation method using 3-aminopropyltriethoxysilane (APTES). The surface and textural of synthesized material have been characterized by using X-ray diffraction (XRD), N2 adsorption isotherms, BET surface area measurement, FT-IR, elemental analyzer and scanning electron microscopy (SEM). The low-angle XRD results indicated that the CuO2(acac)-Thio-APS-MCM41has similar XRD pattern as the mesoporous MCM41 although the intensity decreases. For high-angle XRD, the results show the presence of monoclinic CuO at 2θ = 35.3 and 38.6° while N2 adsorption and BET results were revealed that the CuO2(acac)-Thio-APS-MCM41 possessed a good mesoporous structural ordering and uniform mesoporosity. FTIR spectra confirmed that the organosilane group still retained in the pore channel of the CuO2(acac)-Thio-APS-MCM41 even after modification and the band of C=S and Cu=O also appeared in CuO2(acac)-Thio-APS-MCM41 spectra with the presence of thiourea ligand and copper. Hence, the characterization results were revealed that the synthesized material has an ordered hexagonal structure, a narrow pore size distribution, a high surface area and thiourea complex were successfully grafted onto the pores of functionalized-MCM41.
温和条件下Nb―MCM―41光催化氧化甲烷的研究  [PDF]
辛靖,陈希慧
分子催化 , 2001,
Abstract: 以含水的Nb-MCM-41中孔分子筛为催化剂,在温和条件下光催化氧化甲烷的反应结果表明,硅基Nb-MCM-41的反应活性高于Nb2O5,且有一定量甲醇和微量的甲醛生成。
MCM-48负载SO42-/ZrO2定位催化硝化合成3,4-二甲基硝基苯  [PDF]
奚立民,于红艳
化工进展 , 2010,
Abstract: 采用液相沉积法制备了由MCM–48介孔分子筛负载SO42-/ZrO2的催化剂,探讨了催化剂表面的成酸过程和催化定位硝化反应机理,并以邻二甲苯和硝酸定位硝化反应为探针反应,考察了催化剂的性能;用酸碱滴定、TEM、N2吸附-脱附和Hammett指示法表征了固体超强酸。结果表明,固体超强酸保持了MCM-48的介孔结构,BET表面积高达208m2/g,表面含有质子酸和路易斯酸中心,且具有强酸性(H0<-13.75);得到适宜的工艺条件催化剂培烧温度500℃,反应温度60℃,n(硝酸)/n(邻二甲苯)=2.5,m(邻二甲苯)/m(催化剂)=25,反应时间3h,产物收率为91.8%,含量达到82.1%。
MD模拟研究含金属离子的MCM41对水的吸附  [PDF]
梁世强,徐靖中
工程热物理学报 , 2004,
Abstract: 本文采用MD模拟研究了分别含有Al3+,Cu2+和La3+等金属离子的中孔分子筛MCM41在较大温度范围内对水的吸附情况,通过考察水分子在孔内的局部平均密度分布,发现含有Al3+和La3+的MCM41对水有较好的吸附性能,表现在吸附量提高和脱附温度降低。我们认为其吸附性能提高的主要原因在于引入金属离子导致了壁面极性增加,增加了吸附表面的活性点,改变了壁面分子结构等几个方面。
Modeling of liquid hydrocarbon fuel production from palm oil via catalytic cracking using MCM -41 as catalyst  [PDF]
Ivan Yared,Hengky Kurniawan,Nico Wibisono,Yohanes Sudaryanto
Journal of Engineering and Applied Sciences , 2008,
Abstract: The objective of this study was to determine the reaction kinetics of the catalytic cracking of palm oil over MCM -41 as a catalyst at the higher C/O ratio and WHSV. The kinetic values obtained from this study can be used further for industrial purpose. In this study, palm oil was cracked using MCM -41 as a catalyst in a fixed bed micro-reactor. The experiment was conducted at the atmospheric pressure, with reaction temperature of 623.15 K, 673.15, and 723.15 K, Weight Hourly Space Velocity (WHSV) of 15, 17.5, 20, 22.5, 25, 27.5, and 30 h-1, and C/O (catalyst/oil) ratio of 1:32.5. The kinetic model used in this study was the three-lump model developed by Weekman, which involves parallel cracking of palm oil to Organic Liquid Product ( OLP ) and gas plus coke, with consecutive cracking of the OLP to gas plus coke. The model can represent the experimental data fairly well. From the study, the rate constant values k1, k2, k3 for reaction temperature of 623.15 K were found to be 9.499, 1.8967 and 0.15565 h-1, respectively. For reaction temperature of 673.15 K, the rate constant values were 20.0674, 3.9725 and 0.6330 h-1. For reaction temperature of 723.15 K, the rate constant values were 28.5494, 5.1498 and 0.6768 h-1. Using the Arrhenius equation, the activation energy is 41.5000, 37.7800 and 12.7437 kJ/mol for E1, E2, and E3, respectively. The pre-exponential factor k10, k20, and k30 obtained using the same equations were 30091.6, 2971.14 and 5.82 h-1, respectively.
不同孔径介孔分子筛MCM–41的合成及载药释药性能(英文)  [PDF]
曹渊,白英豪,夏之宁
硅酸盐学报 , 2009,
Abstract: 通过添加辅助剂1,3,5-三甲基苯合成不同孔径的介孔分子筛(mesoporousmolecularsieves,MCM-41)。将利尿性氢氯噻嗪引入到MCM-41的孔道内,采用低温N2吸附-脱附、X射线衍射、Fourier红外光谱仪、热重分析等表征MCM-41材料,并测定了氢氯噻嗪在模拟体液中的释放率。结果表明合成的MCM-41具有均一的介孔结构,孔径在4.0~5.6nm,氢氯噻嗪在MCM-41-B(具有最大的孔径)中的释放速率较快,10h释放了79%,其他材料的需20h,而且氢氯噻嗪的释放速率随着孔径的增加而减小,表明已制得了氢氯噻嗪的缓释体系,并且可以通过控制孔径来调节氢氯噻嗪的释放速率。
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