无机盐水解法制备介孔NiAl2O4纳米粉简

介孔NiAl2 O4材料是常用的电极材料和催化材料,目前常用溶胶-凝胶法制备。本文在不添加任何模板剂和有机溶剂的情况下,通过摩尔比为1！2的硝酸镍和硝酸铝水溶液与碳酸铵水溶液水解的方法制备NiAl2 O4介孔材料。利用热重-差热分析、X射线衍射、扫描电镜观察、透射电镜观察及N2吸附-脱附等测试手段表征。通过800℃焙烧,制备了NiAl2 O4介孔材料,晶粒大小约30 nm,比表面积为105．3 m2/g,平均孔径为7．2 nm,孔容为0．19 cm3/g,孔径分布比较狭窄、规整。     

绿豆环氧水解酶在硅基介孔材料上的固载及催化性能

从绿豆中提取粗酶并优化,活性测定反应条件,结果表明,在40 ℃、pH=7的条件下,酶反应活性最高。将来源于绿豆的环氧水解酶固载于多种硅基介孔材料上,考察了多种因素对固定化酶活性的影响。研究发现,以大孔径、表面疏水性的材料作为载体,采用共价方法固载酶,可以得到较高的酶固载率,同时固载酶表现出较高的催化反应活性,并且可以循环使用多次。     

Synthesis of MgO-Modified mesoporous silica and its adsorption performance toward CO2

The mesoporous silica modifed with magnesium ox- ide （MgO） was syntbesized by one step method and impregnating method, respectively. The samples were characterized by small angle X-Ray diffraction （XRD）, N2 adsorption-desorption and transmission electron microscopy （TEM）, and the carbon dioxide adsorption capacity was analyzed by thermal gravimetric analysis （TGA）. Compared with the original mesoporous silica （20.7 mg/g）, the CO2 adsorption capacity of MgO-modified mesoporous silica processed by one step method increases to 32.9 mg/g. Although its surface area greatly decreases compared with that of the original mesoporous silica, the MgO-modified mesoporous silica prepared by impregnating reaches an adsorptive value of 31.1 mg/g because the number of basic sites increases on the surface of the mesoporous silica.     

HMS表面氨基改性及孔口修饰对固载Salen-Mn的影响

采用常规法、微波法、超声波三种方法将Salen-Mn配合物固载到表面含-NH2的介孔HMS载体上,并在此基础上对HMS的孔口进行改性.用FT-IR,TG-DSC表征催化剂,并用化学络合滴定法测定了Mn的质量摩尔浓度.以E-二苯乙烯环氧化反应考察催化剂的性能.结果表明,含表面-NH2的HMS对Salen-Mn有一定的固载效果,而对载体孔口改性可进一步提高环氧化物的选择性并减少Mn的流失.     

Surface PEGylation of hollow mesoporous silica nanoparticles via aminated intermediate

A hybrid of organic/inorganic system, hollow mesoporous silica nanoparticles functionalized with poly(ethylene glycol), was synthesized in the presence of coupling agent and aminated ends. Doxorubicin (DOX) was used as a model drug to evaluate the effect of PEGylation on the loading capacity and release pattern of the system. Characterization with transmission electron microscopy (TEM) and scanning electron microscopy (SEM), X-ray diffraction (XRD), nitrogen adsorption-desorption, thermogravimetric analysis (TGA) and Fourier transformed infrared (FTIR) confirmed the PEG conjugation, as well as the amorphous mesoporous nature of the synthesized particles. Due to the capping effect of PEG molecules over the pores in the silica structure, the synthesized system was able to retain higher amount of cargo and establish a controlled manner when releasing.     

介孔二氧化锰制备及其催化臭氧氧化草酸研究

采用纳米刻蚀法制备了介孔二氧化锰臭氧催化剂,并考察了其催化臭氧氧化降解草酸的性能.该催化剂高比表面积(142m~2·g~(-1))的有序纳米棒有利于催化剂活性位点的暴露和物质的吸附,从而增强了催化剂的催化活性.羟基自由基是催化臭氧氧化过程中产生的主要活性氧物种,该催化剂的羟基自由基产率是非介孔二氧化锰的2倍;朗缪尔吸附模型表明该催化剂对草酸的吸附能力是非介孔二氧化锰的9.42倍;该催化剂催化降解草酸的准一级反应动力学常数是非介孔二氧化锰的3倍.     

新型介孔钒氧化物催化剂上丙烷高选择性氧化脱氢制丙烯研究

采用醇溶液浸渍法制备了介孔SBA-15、介孔MCM-41及无定形SiO2三种不同氧化硅载体担载的系列钒氧化物催化剂．活性测试结果表明,SBA-15为载体的钒氧化物催化剂具有优良的丙烷氧化脱氢反应性能．BET、SEM/TEM、UV-Vis DRS,TPR,UV Raman和程序升温吡啶-FTIR结果表明：介孔SBA-15载体较大的比表面积及孔径、对钒氧物种较高的分散能力以及催化剂表面仅存在少量的弱酸性位等特点有利于丙烷的活化及产物丙烯的脱附,使得催化剂在丙烷氧化脱氢反应中显示出高活性和高选择性．     

On-line catalytic upgrading of biomass fast pyrolysis products

Pyrolysis-gas chromatography/mass spectrometry （Py-GC/MS） was employed to achieve fast pyrolysis of biomass and on-line analysis of the pyrolysis vapors. Four biomass materials （poplar wood, fir wood, cotton straw and rice husk） were pyrolyzed to reveal the difference among their products. Moreover, catalytic cracking of the pyrolysis vapors from cotton straw was performed by using five catalysts, including two microporous zeolites （HZSM-5 and HY） and three mesoporous catalysts （ZrO2＆TiO2, SBA-15 and AI/SBA-15）. The results showed that the distribution of the pyrolytic products from the four materials differed a little from each other, while catalytic cracking could significantly alter the pyrolytic products. Those important primary pyrolytic products such as levoglucosan, hydroxyacetaldehyde and 1-hydroxy-2-propanone were decreased greatly after catalysis. The two microporous zeolites were ef- fective to generate high yields of hydrocarbons, while the three mesoporous materials favored the formation of furan, furfural and other furan compounds, as well as acetic acid.     

介孔TiO2的水热法合成及其光催化活性研究

以非离子型表面活性剂Triton X-100为模板剂,用水热法制备了介孔TiO2,探究了不同反应条件对样品光催化活性的影响,对制得的样品进行了XRD、SEM、N2吸附-解吸及差热-热重等表征.结果表明,所得样品为窄孔道分布,最可几孔径为3.4 nm,当水热温度为120℃,焙烧温度为400℃,Ti(SO4)2∶OP∶C2H5OH为4∶1∶40(摩尔比)时,所制得样品的可见光催化活性最好.     

水杨醛类Schiff碱配合物在介孔分子筛MCM-41上的组装与表征

目的 研究γ-氨丙基修饰、Schiff类金属配合物修饰对MCM-41六方孔道结构的影响.方法 用元素分析,IR,UV-Vis等方法对所得配合物进行了表征.以十六烷基三甲基溴化铵为表面活性荆,Na_2SiO_3·9H_2O为硅源,用水热合成法在碱性条件下合成了介孔分子筛MCM-41,采用嫁接法使γ-氨丙基三乙氧基硅烷与介孔分子筛MCM-41在无水乙醇中回流12 h,反应得到γ-氨丙基功能化的MCM-41,使该产物与所合成Mn(Ⅲ),Fe(Ⅲ)配合物进行化学组装.结果 合成了4个Schiff配体N,N-双(5-氯水杨醛)缩乙二胺,N,N-双(5-溴水杨醛)缩乙二胺,N,N-双(5-硝基水杨醛)缩乙二胺,N,N-双(5-氯水杨醛)缩邻苯二胺,5个Mn(Ⅲ),Fe(Ⅲ)的过渡金属配合物.用IR,XRD等谱学技术对组装产物进行了初步的表征.组装产物的IR光谱呈现出金属配合物的schiff碱配体相应基团的特征吸收且特征峰位移不明显,配合物成功固载到MCM-41上.XRD谱表明所有组装产物仍保持六方孔道结构.结论 γ-氨丙基修饰、Schiff类金属配合物修饰对MCM-41六方孔道结构没有影响.