铁镧交联蒙脱土的合成及催化氧化性能

以临安钠基蒙脱土为原料,制备了铁交联和铁镧复合交联蒙脱土催化剂,利用物理吸附(BET)、扫描电镜(SEM)和X-射线衍射(XRD)对催化剂进行表征,并以铁镧复合交联蒙脱土(Fe/La-PILC)为催化剂,质量分数为30%的过氧化氢水溶液为氧化剂,考察反应时间、催化剂用量和过氧化氢用量对苯甲醇催化氧化制苯甲醛的影响.结果表明:铁镧复合交联蒙脱土形成了比较均一的中孔骨架结构;当苯甲醇与过氧化氢物质的量之比为1:2,Fe/La(200)-PILC(Fe与La物质的量之比为200)质量分数为4%,反应5 h时,苯甲醇转化率和苯甲醛选择性分别为62.1%和86.4%.研究铁镧交联蒙脱土催化剂的催化氧化机理,发现Fe/La-PILC催化氧化苯甲醇的活性氧来自于Fe/La-PILC所吸附的氧.     

新型蒙脱土催化材料的制备与应用

蒙脱土催化材料是一种新的用途广泛的新型催化材料。本文分别介绍了无机交联蒙脱土催化剂、蒙脱土负载试剂酸催化剂、蒙脱土中孔异构催化材料等的制备、结构及催化应用研究。     

蒙脱土改性催化材料的研究进展

改性蒙脱土是一种用途广泛的催化新材料。分别介绍了酸化蒙脱土酸催化剂、交联蒙脱土催化剂、蒙脱土中孔异构催化材料等的制备、结构及催化应用研究。     

微波法制备铁铜铝交联蒙脱土催化剂的表征及稳定性评价

采用微波法和传统法制备铁铜铝交联蒙脱土(Fe-Cu-Al-MMT)催化剂。通过XRD、BET、SEM、ICP等手段对催化剂进行表征,并考察催化剂的稳定性。结果表明,微波法制备的Fe-Cu-Al-MMT催化剂层间距d 001为1.806 nm,比表面积为175.1 m^(2)·g^(-1);相比于传统法制备的铁铜铝交联蒙脱土催化剂层间距和比表面积略有增加,而催化剂的稳定性增加明显。     

铝层柱蒙脱土的制备研究

采用铝交联剂交联蒙脱土,制备了不同Al/MMT配比的铝层柱蒙脱土,并采用XRD、吡啶吸附红外进行了表征,研究了铝层柱蒙脱土的水热稳定性及其表面酸性.研究表明,在500℃下焙烧8～12 h,有效改善了Al-MMT蒙脱土的水热稳定性,铝层柱蒙脱土酸类型和酸强度可以通过改变铝与蒙脱土的配比来实现.     

Cu_2O/蒙脱土复合催化剂的制备及其光催化性能

本文以化学沉淀法制备了Cu_2O/蒙脱土复合光催化剂,以亚甲基蓝的光催化降解为探针反应测试了Cu_2O/蒙脱土复合催化剂的光催化活性,并研究了Cu_2O的负载量、复合催化剂用量、溶液pH值和亚甲基蓝初始浓度等对Cu_2O/蒙脱土复合催化剂光催化活性的影响。研究结果表明pH=11、50%Cu_2O/蒙脱土复合催化剂投加量为0.2g/L、亚甲基蓝溶液浓度为10mg/L时,可见光照射120min后,降解效率可达到91%。     

交联蒙脱土催化剂底面间距的测定

通过X射线衍射测定了一系列羟基混合金属柱交联蒙脱土的底面间距,并考察了制备条件、焙烧温度等对交联蒙脱土底面间距的影响。结果发现蒙脱土经交联之后底面间距有较大的增加;采用共混法、焙烧温度在500℃时制得的催化剂具有较大的底面间距;另外,羟基混合金属柱中各种金属离子的比例对交联蒙脱土的底面间距有较大的影响。     

表面活性剂改性的铝交联蒙脱土的表征及催化性能

以聚乙烯醇为支撑前体，合成了一类新型的表面活剂改性的铝交联蒙脱土。通过ＸＲＤ，低温Ｎ２脱吸附分析，骨架振动红外光谱等手段的表征及对催化转化柴油为汽油的测试，表明热稳定性与催化活性传统的铝交联蒙脱土都有显著提高。     

反相悬浮法制备粘土复合高吸水性树脂

以丙烯酸和蒙脱土为主要原料,采用反相悬浮法合成了聚丙烯酸钠/蒙脱土复合高吸水性树脂,研究了交联剂用量、蒙脱土用量等因素对树脂吸液性能的影响,确定了最佳实验条件,在此条件下制备的复合树脂对去离子水和0.9%NaC l水溶液的吸水率分别为800g/g和92g/g,适量蒙脱土的加入可提高吸水性树脂的保水性能,FTIR初步表明蒙脱土与聚丙烯酸钠之间发生了交联反应。     

蒙脱土担载钴配合物催化剂制备及性能研究

制备了系列蒙脱土担载钴(Ⅱ)(Co(Ⅱ))配合物催化剂,并对其结构进行了X射线衍射和透射电镜等表征,初步研究了蒙脱土担载钴(Ⅱ)配合物催化剂对烯烃的催化氧化性能.结果表明:配体进入了蒙脱土的片层间与Co(Ⅱ)配位,形成蒙脱土担载的铜配合物复合催化材料;在催化剂催化H2O2氧化苯乙烯的反应中,对苯甲醛和环氧苯乙烷的选择性高达94.7%,转化率达到38.4%;在环己烯的氧化反应中,对环氧环己烷、环己醇、环己烯醇和环己烯酮的选择性共达到98.5%,转化率达到33.2%.     

新型无机铝离子/蒙脱石复合材料催化合成DOP的研究

研究了新型无机铝离子 /蒙脱石复合材料催化剂的制备方法 ,最佳合成条件为 0 2mol/L三氯化铝水溶液与 0 1mol/L氢氧化钠水溶液的体积比为 1∶5 ;保温时间 48h ;保温温度 95℃ ;搅拌时间为 4d ,在此最佳合成条件下制得的催化剂用于合成DOP的酯化率可达 92 %。并对催化剂进行了X射线能谱表征。     

载体SIAL对丙烷氨氧化催化剂的影响

详细研究了丙烷氨氧化催化剂载体SIAL的组成及其相对合且对反应结果的影响。实验发现：载体中Al2O3与SiO2的重量比存在一个最佳值，当Al2O3／SiO2在2．0～2．5时，丙烯腈的收率取得最大值；随着催化剂中载体相对含量的增大，其反应效果得到明显的改观：丙烷的转化率随载体含量的增加而增大，而丙烯腈的选择性在载体／活性组分（重量比）在三1．5附近达到最大，此时COx的选择性最小，当该比例在1．5～2．5时丙烯腈的收率达到最大值。     

TRANSIENT RESPONSE ANALYSIS IN THE DETERMINATION OF ADSORPTION RATE COEFFICIENTS FOR PROPYLENE AND NITRIC OXIDE ON NiO/Al203 AEROGEL CATALYSTS

Nickel oxide on alumina aerogel catalysts are known to be active and selective for the formation of acrylonitrile from nitric oxide and propylene. During an effort to investigate the mechanism of this reaction some transient feed experiments were carried out. The results obtained from these transient experiments were used to calculate the adsorption coefficients of propylene and nitric oxide on a NiO/Al₂O₃ aerogel catalysts with 1:1 Ni to Al atomic ratio. Adsorption coefficients of nitric oxide and propylene was determined by independently flowing the respective gases over the catalyst in a stream of helium at 410° C. Adsorption coefficient of nitric oxide on the catalyst at an oxidized state has been found to be less than that of propylene. When the two reactant gases flowed across the catalyst together the rate of adsorption of nitric oxide increased as the catalyst was reduced by propylene adsorption. The increased rate of adsorption of nitric oxide does not, however, influence the overall rate of formation of acrylonitrile.     

TRANSIENT RESPONSE ANALYSIS IN THE DETERMINATION OF ADSORPTION RATE COEFFICIENTS FOR PROPYLENE AND NITRIC OXIDE ON NiO/Al203 AEROGEL CATALYSTS

Nickel oxide on alumina aerogel catalysts are known to be active and selective for the formation of acrylonitrile from nitric oxide and propylene. During an effort to investigate the mechanism of this reaction some transient feed experiments were carried out. The results obtained from these transient experiments were used to calculate the adsorption coefficients of propylene and nitric oxide on a NiO/Al₂O₃ aerogel catalysts with 1:1 Ni to Al atomic ratio. Adsorption coefficients of nitric oxide and propylene was determined by independently flowing the respective gases over the catalyst in a stream of helium at 410° C. Adsorption coefficient of nitric oxide on the catalyst at an oxidized state has been found to be less than that of propylene. When the two reactant gases flowed across the catalyst together the rate of adsorption of nitric oxide increased as the catalyst was reduced by propylene adsorption. The increased rate of adsorption of nitric oxide does not, however, influence the overall rate of formation of acrylonitrile.     

Fe-Al催化剂催化丙烯腈与甲基丙烯酸丁酯聚合

以Fe(acac)3-Al(i-Bu)3(acac表示乙酰丙酮)催化体系催化丙烯腈(AN)与甲基丙烯酸丁酯(BMA)聚合,考察了聚合规律,用红外光谱和差热分析研究了共聚物结构,凝胶渗透色谱研究了共聚物分子量及其分布。动力学实验表明聚合对单体浓度呈一级反应,表观活化能为46.1 kJ/mol。     

Effect of hydroxy-aluminium species on the sorption and interlayering of albumin onto montmorillonite

Proteins interact with soluble OH–Al species or Al precipitation products forming organo-mineral complexes with different chemical and physico-chemical properties. We studied the effect of pH, cation saturating the clays, presence of OH–Al species and order of component (OH–Al species, albumin and montmorillonite) addition on the amounts of proteinic molecules adsorbed on montmorillonite and the possible interlayering of OH–Al–protein complexes. Albumin molecules were very well intercalated into the interlayers of Na-montmorillonites, but very poor or no intercalation was observed for Mg-saturated montmorillonite and for an Al(OH)_x-montmorillonite (chlorite-like) complex.We have found that the amount of albumin sorbed on the external and interlamellar spaces of montmorillonite in the presence of OH–Al species was influenced by the sequence of addition of albumin (Alb), OH–Al species (Al) and montmorillonite (Mt). Complexes were prepared by mixing: (i) Al+Mt before Alb; (ii) Al+Alb before Mt; and (iii) Alb+Mt before Al. When albumin was added to montmorillonite before OH–Al species (Alb+Mt before Al complexes) proteinic molecules were able to penetrate more easily into the interlayers of montmorillonite. On the contrary, when OH–Al species were initially added to the clay (Al+Mt before Alb complexes), they were previously interlayered and consequently prevented the intercalation of the proteinic molecules. Finally, when OH–Al species and proteins were added to the clay as a mixture (Al+Alb before Mt complexes), large OH–Al–protein polymers formed, which were only partially intercalated into the interlamellar spaces of the clay. In all the complexes, the amounts of proteinic molecules sorbed usually increased by increasing the pH.     

A Study on Physical Properties of Melt Blended Acrylonitrile Butadiene Styrene/Ethylene Vinyl Acetate Modified with Linear Low Density Polyethylene and Montmorillonite

In this study, acrylonitrile butadiene styrene/ethylene vinyl acetate-based melt blends were prepared using linear low-density polyethylene as modifier. Commercially available sodium montmorillonite clay was organically modified and incorporated in blends. Fourier transformed infrared was used to confirm the structure of the blend and composites. Morphology of acrylonitrile butadiene styrene / ethylene vinyl acetate blend showed two-phase structure that formed a well-aligned pattern with fine nanoclay distribution. Addition of organo-modified clay depicted increase in tensile strength (43%) and modulus (89%) in damage-free range. XRD results of sodium montmorillonite, organically modified Na-montmorillonite, and PNCs were compared to investigate the degree of dispersion in matrix.     

蒙脱土负载三氯化铁氧化苯偶姻制备苯偶酰

以酸处理蒙脱土K10为载体,采用浸渍法制备出环境友好的蒙脱土负载FeCl3催化氧化剂,利用红外光谱对其进行了表征。研究了FeCl3的负载量和活化温度对氧化反应的影响。并分别以蒙脱土K10,SiO2,Al2O3为载体制成三氯化铁负载试剂氧化剂,比较了不同载体对催化氧化反应活性的影响。结果表明,蒙脱土K10为本反应的良好载体。以蒙脱土K10负载三氯化铁为催化剂,氧化苯偶姻制备苯偶酰,具有操作简便、反应产物易于分离、氧化剂选择性高等优点。当氧化剂与苯偶姻摩尔配比为1∶1时,在回流温度下氧化反应4 h,苯偶酰的产率为91.8%,其结构经熔点测定和红外光谱表征。     

HMT催化乙烯聚合制备纳米复合材料

在蒙脱石有机化过程中,采用无水乙醇取代去离子水作为溶剂,使蒙脱石有机化时残留的无水乙醇对MgCl2进行改性,生成活性更高的促进剂烷氧基镁,然后与液态TiCl4反应进行载钛,制备了一种新型蒙脱石负载型催化剂(HMT)。采用该高活性催化剂,以“原位配位聚合法”制备出性能优异的聚乙烯,蒙脱石纳米复合材料。HMT活性为MT催化剂的3～4倍,其制备方法简单易行,省略了乙醇脱出步骤、烷基铝处理有机蒙脱石的工序．减少了干燥过程,降低了催化剂的制备成本。     

Catalytic activity of polymer–montmorillonite composites in chemical reactions

Polymer–clay composite material has been prepared by intercalation of polymeric ammonium salt onto the montmorillonite (Na–MMT) followed by grafted polymerization of hydroxyethyl methacrylate onto amine‐terminated poly(butadiene‐co‐acrylonitrile)–montmorillonite (ATBN–MMT) intercalate. The hydroxyl groups were modified to chloromethyl groups followed by conversion to onium salts, which are suitable as phase transfer catalysis. The catalytic activities of the supported catalysts were investigated in nucleophilic reactions of thiocyanate and cyanate ions with alkyl and aryl halides. The rates of the reactions have been investigated under different factors such as the nature and structure of the support, the amount of catalyst, the solvent, and the temperature. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1121–1129, 2006