Alkylation of aniline withn-propyl alcohol over zeolites

The alkylation of aniline withn-propyl alcohol over ZSM-5 and Y zeolites has been studied. Ce-exchanged Y zeolites proved to be the most active for the alkylation of aniline byn-propyl alcohol. The reaction of N-propylaniline over zeolites has been investigated. N-alkylaniline decomposed over zeolites to aniline and alkene, which in turn rearrange to C-alkylanilines.n-Propyl derivatives were formed through an SN₂ type mechanism, while isopropyl derivatives were formed by an SN₁ type mechanism.     

Surface chemical modification of zeolites and their catalytic performance for naphthalene alkylation

Acid-catalyzed naphthalene alkylation products, such as 2,6-dialkylnaphthalenes (2,6-DAN), are industrially important compounds used to make monomers for advanced polymer materials [1]. Zeolite molecular sieves can be extensively used in many catalytic applications, specifically in naphthalene alkylations due to their high activity and stability as well as their high selectivity. The initial studies have mainly focused on gas phase alkylation of naphthalene with methanol, and only obtained th…     

HY沸石上2,6-二叔丁基萘的择形合成

 研究了脱铝HY沸石（n（Si）／n（Al）＝3．8）上萘（naph）的\r\n选择性叔丁基化反应．结果表明，八面沸石对该反应过程有较好的择形\r\n催化作用，两种异构化产物（2，6－二叔丁基萘和2，7－二叔丁基萘）\r\n之间存在着热力学平衡，即两种异构化产物可在酸性中心位上相互转化\r\n．在以叔丁醇为烷基化试剂，WHSV＝2h－1，n（t－BuOH）／n（naph）\r\n＝3，反应温度为120℃的反应条件下，萘的转化率可达98．43％，β－\r\n位选择性可高达100％，二叔丁基萘收率可达74．34％，2，6－二叔丁\r\n基萘／2，7－二叔丁基萘质量比为6．24．     

沸石分子筛催化剂上萘的择形异丙基化反应性能

 研究了HY,Hβ,HM和HZSM－5沸石分子筛对萘择形异丙基化反应的催化性能．结果发现,这些沸石分子筛的活性顺序为HY＞Hβ＞HM＞HZSM－5,对2,6－二异丙基萘的选择性顺序为HM＞Hβ＞HY．除沸石分子筛的酸量与酸分布外,其孔道结构与大小是影响萘异丙基化反应的主要因素．脱铝能选择性地降低沸石外表面的酸性,且对沸石的催化性能有较大影响．常压水蒸气脱铝结合强酸再处理有利于催化剂催化性能的提高．提高反应温度有利于萘的转化,但温度过高会引发许多副反应,适宜的反应温度约为523K．反应时间对产物分布的影响不明显．异丙醇／萘摩尔比应小于2．     

萘与丙烯在脱铝丝光沸石上的烷基化反应

Shape selective alkylation of polynuclear aromatics has begun to receive increasing attention. 2,6 dialkylnaphthalenes are important raw materials for manufacturing high quality polyester fibers and plastics. Understanding of the reaction and the catalysis for conversion of polycyclic aromatic hydrocarbons is needed both from fundamental and practical view points. In this paper, alkylation of naphthalene with propene over a series of dealuminated mordenite with different Si/Al ratios was carried out in an autoclave with an electromagnetical stirrer. Textural property of the dealuminated mordenite was determined by nitrogen adsorption. The amount of the acid sites was measured by NH 3 TPD. The catalytic activity of HM and β shape selectivity for products increased with increasing the Si/Al ratio in HM. Moreover, the selectivity for alkylation with propene was also increased by dealumination treatment. The increase of the catalytic activity was attributed to the formation of mesopores, which significantly promoted the diffusion of reactants and products in mordenite. It was suggested that the increase of β selectivity resulted from the elimination of acid sites from the external surface, and the selectivity for alkylation with propene was improved owing to the creation of the interconnection between 12 ring and 8 rimg channels by dealumination.     

在H型分子筛上萘与正己醇的烷基化反应

制备了H型分子筛HY,Hβ和HM,通过XRD,NH₃-TPD和Py-IR对其进行了表征,考察了其对萘与正己醇的烷基化反应的催化性质.结果表明,HY可作为己基化反应的催化剂,较高的反应温度和较长的反应时间对β-己基萘的生成有利.     

Photocatalytic isomerization of norbornadiene over Y zeolites

K, Zn, Cs and La ion-exchanged Y zeolites were prepared and used as photocatalysts for the isomerization of norbornadiene. The prepared catalysts were characterized by EDS, XRD, ²⁷Al- and ²⁹Si-NMR, UV-vis and IR. The La-exchanged sample showed the highest degree of exchange, but accompanied with some dealumination. La-exchange generated both B-acid and L-acid sites, whereas other metals produced only L-acid sites. For the photocatalytic isomerization reaction, the activity order was LaY > CsY > ZnY > KY. The heavy atom effect and B-acidity are expected to play important roles in the reaction.     

煤焦油萘择形异丙基化产物组成的气相色谱/质谱分析

 采用毛细管气相色谱 /质谱 (CGC/MS)联用技术 ,经计算机质谱库检索并结合人工谱图解析 ,研究了在不同沸石分子筛催化剂上煤焦油萘择形异丙基化产物的组成。研究结果表明 ,煤焦油萘异丙基化产物主要由一取代萘、二取代萘以及少量三取代萘组成 ;除 HZSM-5活性较低以外 ,其它催化剂均有较高的反应活性 ,其中 HY和 Hβ反应活性最高 ,萘转化率分别达 75 .1 5 %和 5 5 .96% ,但β位产物的选择性较差 ;ZM类催化剂既有一定的活性 ,又有较高的β选择性 ,是萘择形异丙基化反应理想的备选催化剂。     

Alkylation of Phenol with Methanol over Basic X Zeolites

Alkylationofphenolprovidesmanyindustrialintermediatessuchasagrochemicalsandpolymers.Thealkylationofphenolwithmethanolproceedsviaoxygen(O)-alkylationproducinganisole(An)aswellasmethylanisoleisomers(InAn)andring(C)-alkylationproducingmainlycresols(m.p.o-Cr)aswellasxylenols(Xy).Vapor-phasealkylationofphenolwithmethanolhasbeenexaminedovervarioussolidcatalysts'-'.Thecatalyticpropertiesandtheproductselectivityarestfonglyaffectedbythestructureofcatalystinadditiontoacidic-basiccharacter.Strongacidc…     

Catalyst activity comparison of alcohols over zeolites

Alcohol transformation to transportation fuel-range hydrocarbon over HZSM-5 (SiO₂/Al₂O₃ = 30) catalyst was studied at 360 °C and 300 psig. Product distributions and catalyst life were compared between methanol, ethanol, 1-propanol and 1-butanol as a feed. The catalyst life for 1-propanol and 1-butanol was more than double compared with that for methanol and ethanol. For all the alcohols studied, the product distributions (classified to paraffin, olefin, naphthene, aromatic and naphthalene compounds) varied with time on stream (TOS). At 24 h TOS, liquid product from 1-propanol and 1-butanol transformation primarily contains higher olefin compounds. The alcohol transformation process to higher hydrocarbon involves a complex set of reaction pathways such as dehydration, oligomerization, dehydrocyclization and hydrogenation. Compared with ethylene generated from methanol and ethanol, oligomerization of propylene and butylene has a lower activation energy and can readily take place on weaker acidic sites. On the other hand, dehydrocyclization of the oligomerized products of propylene and butylene to form the cyclic compounds requires the sites with stronger acid strength. Combination of the above mentioned reasons are the primary reasons for olefin rich product generated in the later stage of the time on stream and for the extended catalyst life time for 1-propanol and 1-butanol compared with methanol and ethanol conversion over HZSM-5.     

Kinetic evaluation of hydrogenation of sucrose over ruthenium containing Y zeolites

Hydrogenation of sucrose over Ru/NaY, Ru/USY and Ru/CaY catalysts was carried out in a slurry reactor at 135°C and 12 atm. The catalysts were prepared by ion exchange followed by calcination and reduction. These were characterised as AA, TPR, DTA/TGA, H₂/Chemisorption, CO-FTIR, XRD and t-plot. To describe kinetic product distribution, the 4^th order Runge-Kutta method was used for determining the kinetic parameters.     

纳米HZSM-5催化剂催化烃类转化反应

制备了纳米(20~50 nm)HZSM-5催化剂, 用XRF, TEM和NH3-TPD等手段对催化剂进行了表征. 以正辛烷及苯和正辛烷混合物的转化为模型反应, 研究了单烃和混合烃在纳米HZSM-5催化剂上的转化行为, 考察了反应条件对产物分布的影响. 结果表明, 纳米HZSM-5沸石催化剂具有很强的烃类转化能力, 烃类通过芳构化、 异构化和烷基化等反应转化为高辛烷值的异构烷烃和芳烃, 产物中异构烷烃(C4~C6)和芳烃的质量分数超过90%. 直链烷烃转化为芳烃以生成苯环为主, 混合烃转化为芳烃以苯和小分子烃的烷基化为主. 控制反应条件可抑制苯和C+9芳烃的生成. 产物分析结果表明, 烃类在纳米HZSM-5催化剂上的裂解、芳构化和异构化等遵循正碳离子机理.     

Highly efficient and green synthesis of diacylphloroglucinol over treated natural zeolite mordenite and the optimization using response surface method (RSM)

Herein, we report a greener and highly efficient route for the Friedel-Craft acylation of phloroglucinol over Indonesian treated natural zeolite mordenite (nHZMOR) catalyst to provide value-added diacylphloroglucinol derivatives under solvent-free conditions. The nHZMOR showed a high catalytic performance in Friedel-Craft acylation of a phloroglucinol reaction, and diacylphloroglucinol derivatives were obtained in excellent yields. The advantages of the use of this catalyst are solvent-free, shorter reaction time, high yields, and its recyclable ability. Easy catalyst separation was demonstrated through filtration and reused several times without noticeably decreasing its catalytic activity; however, with regeneration treatment, its catalytic performance can be improved. The effect of catalyst loading, reaction temperature, solvent effect and reaction time has been extensively studied. In addition, the chemical process was enhanced by the use of coupling automated synthesis equipment with the Response Surface Method (RSM) to optimize the Friedel-Craft acylation reaction. Also, a reasonable reaction mechanism had presented.     

Liquid-phase degradation of HDPE over alkali-treated MFI zeolites with mesopores

The catalytic activities of MFI zeolites treated with NaOH solutions of various concentrations were investigated in the liquid-phase degradation of HDPE. The changes in the crystallinity, pore structure and acidity of MFI zeolites according to the alkali treatment were also examined. The parent MFI zeolite composed of large particles showed very poor activity, but the treatment with moderate NaOH solutions of 0.4-0.7 N enhanced considerably the catalytic activity of MFI zeolite by enlarging its external surface area due to the formation of mesopores. The activity of MFI zeolite was improved by about 20 times treated with 0.5 N NaOH solution. The formation of mesopores also contributed to the enhancement of the yield of liquid products by suppressing further cracking due to the rapid diffusion of products. The treatment with strong NaOH solution, however, lowered the catalytic activity because the treatment caused the loss of both crystalline structure and strong acid sites.     

晶种数量对MOR分子筛上烷基转移反应的影响及反应机理研究

以丝光沸石(MOR)分子筛为催化剂,甲苯与三甲苯烷基转移反应为探针反应,系统考察了晶种数量变化对分子筛物化性能和催化性能的影响。研究表明,合成过程中晶种添加量的不同会显著影响催化剂的酸性、比表面积和孔体积,进而影响其催化剂活性和稳定性。当晶种添加量为8%时,MOR分子筛具有最多的B酸含量、最大的比表面积和孔体积,同时对应的催化剂活性和稳定性也最好。本研究还对甲苯和三甲苯烷基转移反应机理进行了深入研究,结果表明,发生在MOR分子筛上的烷基转移反应通过双分子中间体机理进行,并应用实验手段捕捉到了中间体的存在,证实了双分子中间体机理的合理性,同时推导出可能的反应机理路线图。     

沸石配位阳离子对Pd/H-ZSM-5催化剂加氢性能的影响

选用商业多级孔NH4-ZSM-5和H-ZSM-5(NH4-ZSM-5在550℃空气气氛中焙烧6 h)沸石为载体,H2PdC14为金属前驱物,采用常规浸渍法制备了Pd/H-ZSM-5负载催化剂.利用X射线衍射、扫描电子显微镜、N2吸附-脱附、紫外可见光谱、X射线光电子能谱、氨气-程序升温脱附和透射电子显微镜等手段对所制备...     

钝化萘衍生物的磺化反应研究

研究了带吸电子取代基的一系列钝化萘衍生物与SO~3进行的磺化反应, 用^1H NMR分析反应混合物的组成.1-萘磺酸以71:20:9的比例产生1,5-, 1,6-和1,7-萘二磺酸, 进一步磺化得到1,3,5-, 1,3,6-萘三磺酸和1,3,5,7-萘四磺酸. 1-萘甲醛的单硫化得到比例为55:9:6:30的5-, 6-,7-和8-磺酸取代物. 1-苯甲酮萘则以83:11:6的比例得到5-,6-,和7-磺酸取代物. 1-硝基萘仅得到5位磺化产物. 1-萘甲酸和1-萘甲酸甲酯得到5位和8位取代产物. 所有的2位取代萘衍生物均先得到5和8位取代产物. 提出了生成SO~3络合物及迫位磺化的历程.     

Selective catalytic reduction of nitric oxide with ammonia over Fe-Cu modified highly silicated zeolites

In the present study, the solid-state ion exchange method (SSIE) was applied to introduce iron and copper into highly silicate zeolites: beta (BEA, Si/Al = 12.5), ferrierite (FER, Si/Al = 10) and mordenite (MOR, Si/Al = 10). The activity of the prepared samples in the selective catalytic reduction of NO with ammonia (NH₃-SCR) was measured. The highest performance was recorded for Cu-Fe-BEA followed by Cu-Fe-MOR while Cu-Fe-FER showed a low catalytic activity over the entire reaction temperature range. It is shown in this study that the zeolite framework is one of the parameters controlling the amount, environment and distribution of metal species formed during the ion exchange process in Cu-Fe-zeolite catalysts.     

USY分子筛催化FCC汽油的烷基化脱硫反应研究

以USY分子筛催化FCC汽油中噻吩类硫化物与烯烃的烷基化反应,采用DL-2B-EE微库仑仪测定反应前后硫分布的变化,考察了USY分子筛的制备条件和烷基化反应温度对其催化性能的影响.实验结果表明,水蒸汽处理温度350℃、水蒸汽处理时间5h,反应温度120℃时,USY分子筛催化剂的比表面积为613m2/g,催化活性最佳,使得FCC汽油中<100℃馏分的硫含量减少至16.92mg/L.水蒸汽流速对USY分子筛催化烷基化反应影响不大.不同处理方法所得USY分子筛的吡啶吸附红外光谱结果表明,具有较多的酸中心的USY分子筛更有利于催化FCC汽油的烷基化脱硫反应.     

萘相吸光光度法研究

本文以萘作为固体萃取剂，以镍－丁二酮肟显色体系为例进行实验，探索出一种新的固相吸光光度法－萘相吸光光度法。镍在０－１００μｇ／５０ｍＬ范围内符合比耳定律，方法应用于水样中痕量镍的分析，结果良好。此种新的分析方法分离富集和显色测定两步相结合。灵敏度高，选择性好，快速简便，是一种很有发展前途的痕量元素分析方法。