HMCM-22分子筛催化1,3-苯并二噁茂烷类化合物合成的研究

研究了HMCM-22分子筛催化邻苯二酚与环己酮、丁酮、丙酮、丙醛、丁醛、异丁醛、戊醛、异戊醛、正己醛、正辛醛、苯甲醛、二苯甲酮等十余种醛(酮)的缩合反应.考察了反应时间、酚与醛(酮)的配比、HMCM-22分子筛用量等因素对酚与醛(酮)反应的影响.结果表明,当酚与醛(酮)摩尔比为1∶1.4,催化剂用量为3.5 g/1mol醛(酮),反应5 h,选择性一般在97%以上,转化率也一般在70%以上,表明HMCM-22分子筛对邻苯二酚与醛(酮)的反应有较好的催化性能.     

HAIMCM-41介孔分子筛催化1，3-苯并二嗯茂烷合成的研究

研究了HAlMCM-41分子筛催化邻苯二酚与环己酮、丁酮、丙酮、丙醛、丁醛、异丁醛、戊醛、正己醛、正辛醛、苯甲醛、二苯甲酮等十余种醛(酮)的缩合反应.考察了反应时间、酚与醛(酮)的配比、HA1MCM-41分子筛用量、硅铝比、催化剂重用次数等因素对邻苯二酚与醛(酮)反应的影响.结果表明,当邻苯二酚与醛(酮)物质的量比为1:1.4,催化剂用量为3.5g/mol邻苯二酚,反应4h,分子筛n(SiO_2)/n(Al_2O_3)为15时,选择性一般在99.4%以上,转化率也一般在85.6%以上,因此,HAlMCM-41分子筛对邻苯二酚与醛(酮)的反应有较好的催化性能.     

HAlMCM-41介孔分子筛催化1,3-苯并二噁茂烷合成的研究

研究了HAlMCM-41分子筛催化邻苯二酚与环己酮、丁酮、丙酮、丙醛、丁醛、异丁醛、戊醛、正己醛、正辛醛、苯甲醛、二苯甲酮等十余种醛(酮)的缩合反应. 考察了反应时间、酚与醛(酮)的配比、HAlMCM-41分子筛用量、硅铝比、催化剂重用次数等因素对邻苯二酚与醛(酮)反应的影响. 结果表明, 当邻苯二酚与醛(酮)物质的量比为1∶1.4, 催化剂用量为3.5 g/mol邻苯二酚, 反应4 h, 分子筛n(SiO₂)/n(Al₂O₃)为15时, 选择性一般在99.4%以上, 转化率也一般在85.6%以上, 因此, HAlMCM-41分子筛对邻苯二酚与醛(酮)的反应有较好的催化性能.     

HY分子筛催化1,3-苯并二噁茂烷类化合物合成的研究

研究了HY分子筛催化邻苯二酚与环己酮、丁酮、丙酮、丙醛、丁醛、异丁醛、戊醛、异戊醛、正己醛、正辛醛、苯甲醛、二苯甲酮等十余种醛(酮)的缩合反应。考察了反应时间、酚与醛(酮)的配比、HY分子筛用量等因素对酚与醛(酮)反应的影响。实验发现,当邻苯二酚与醛(酮)摩尔比为1∶1.0、催化剂用量为每mol邻苯二酚2.5g、反应4h,选择性一般在97%以上,醛(酮)的转化率一般在57%以上,表明HY分子筛对邻苯二酚与醛(酮)的反应有较好的催化性能。     

HY分子筛催化1,3-苯并二(噁)茂烷类化合物合成的研究

研究了HY分子筛催化邻苯二酚与环己酮、丁酮、丙酮、丙醛、丁醛、异丁醛、戊醛、异戊醛、正己醛、正辛醛、苯甲醛、二苯甲酮等十余种醛（酮）的缩合反应.考察了反应时间、酚与醛（酮）的配比、HY分子筛用量等因素对酚与醛（酮）反应的影响.实验发现,当邻苯二酚与醛（酮）摩尔比为1：1.0、催化剂用量为每mol邻苯二酚2.5g、反应4h,选择性一般在97%以上,醛（酮）的转化率一般在57%以上,表明HY分子筛对邻苯二酚与醛（酮）的反应有较好的催化性能.     

Hydrogenolysis of glycerol over HY zeolite supported Ru catalysts

An enhanced active and selective catalyst consisting of ruthenium supported on dealuminated HY zeolite has been prepared by a wet impregnation method. It was found that BET surface area of Ru/HY catalysts significantly increases after HCl treatment. This treatment also increases the concentration of strong acid sites in the catalyst. The hydrogenolysis of glycerol over 5 wt% Ru/HY catalyst was investigated at 190-220 ℃, an initial H2pressure of 3-6 MPa, and in 20 wt% glycerol aqueous solution. The results indicate that HCl treated Ru/HY catalyst shows higher activity compared with the untreated Ru/HY catalyst, and that the glycerol hydrogenolysis efficiency is influenced by the porosity and acidity of the support. A selectivity to 1,2-PDO of 81.3% at a glycerol conversion of 60.1% under 3 MPa H2pressure and 220 ℃ for 10 h was achieved over the modified Ru/HY catalyst with a 1.0 mol/L HCl treatment. It has also been shown that a longer reaction time, a higher temperature and a higher H2pressure have the positive effects on the glycerol hydrogenolysis efficiency of the enhanced Ru/HY.     

甲基噻吩在HY分子筛上的吸附、脱附及转化行为

由NH₄Y分子筛制备了HY分子筛,运用N₂吸附、NH₃-TPD和Py-FTIR等手段表征HY分子筛的物化性能;采用智能重量分析仪(IGA)方法研究了甲基噻吩(2-甲基噻吩、3-甲基噻吩)在HY分子筛上的吸附-脱附行为;采用程序升温脱附-质谱(TPD-MS)联用手段研究了甲基噻吩在HY分子筛上的转化行为。结果表明,在200 ℃下 2-甲基噻吩和3-甲基噻吩在HY分子筛中的强B酸上发生强化学吸附作用,与B酸结合后生成了甲基噻吩的碳正离子结构进而发生了歧化反应、脱烷基反应以及裂化反应;与2-甲基噻吩不同的是,3-甲基噻吩与HY通过一定的氢转移反应生成了3-甲基四氢噻吩,且200 ℃吸附条件下3-甲基噻吩比2-甲基噻吩更容易发生裂化反应。     

Reactivities of tetraalkyltin complexes toward Pt/HY zeolite

Tetraalkyltin complexes, SnR₄ (R = Me, Et, Pr, Bu) could react with Pt/HY at 193, 243, 273 and 333 K, respectively. The reactions occurred on the surface of the zeolite and the organotin grafted zeolites were characterized in detail. The framework and the microporous structure of the grafted Pt/HY zeolites were retained. However, the modified zeolites showed better size selectivity in the absorption of hydrocarbons.     

CO2 poisoning effect on HY zeolite dehydration catalyst

The poisoning effect of CO₂ on a HY catalyst for the dehydration of 2-(2-hydroxyethyl)-pyridine (HEP) to 2-vinylpyridine (VP) has been investigated by FT-IR analysis in the presence and absence of pyridine. CO₂ was found to adsorb on sites not occupied by pyridine,i.e. on weak basic sites accompanying the strongly acidic sites, characteristic of Y zeolites in the protonated form. When the basic sites are occupied by preadsorbed CO₂, HEP dehydration cannot take place any more through the minor mechanism, involving a couple of acid-base sites, and the reaction proceeds only through the major mechanism, involving a carbocation intermediate, on Br?nsted acid sites only.     

Silicalite-1修饰的HY型分子筛及其对纤维素水解的催化性能

采用silicalite-1对HY型分子筛进行修饰,得到具有核壳结构的复合分子筛HY/silicalite-1。通过X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、N2的吸附-脱附及吡啶吸附红外(Py-FTIR)等手段对不同晶化时间合成的HY/silicalite-1复合分子筛进行了表征,研究了复合分子筛对纤维素水解的催化性能。结果表明,晶化时间直接影响复合分子筛的晶体生长规律和两组分的相对含量,最佳晶化时间为16-24 h,所得到的复合分子筛外貌呈核壳结构,silicalite-1附晶生长在HY型分子筛的表面;随着晶化时间的延长,复合分子筛的表面由胶浊状变为光滑,最终变为鳞片状;其B酸量先减少后增加,而L酸量则先增加后减少。其中,晶化时间为24 h的HY/silicalite-1复合分子筛B酸量最大,L酸量最小,对纤维素水解反应具有良好的催化性能,葡萄糖收率由HY型分子筛催化获得的28.0%大幅提高至45.8%。     

甲醇在HY分子筛上合成异构烃的研究

在以分子筛为催化剂的甲醇转化研究领域中,最为成功的是甲醇在ZSM-5分子筛上转化制汽油的研究。由于在孔道结构以及酸性质上,ZSM-5型分子筛有着不同于HM、HY等其他分子筛的特点,使得它在甲醇转化制汽油的反应中有着其他分子筛不可比拟的优势。     

Smooth photocatalytic preparation of 2-substituted 1,3-benzodioxoles

A mild and general method for the synthesis of potentially bioactive 2‐substituted‐1,3‐benzodioxoles is presented. This is based on the photocatalyzed activation of methylene hydrogen atoms in the presence of tetrabutylammonium decatungstate (TBADT). The method gave yields ranging from 46–77 % with no interference by benzene ring substituents, such as OR, COOMe, Me, or CHO. The OH group interfered, but protection regenerated the reactivity. 5‐Chloro‐1,3‐benzodioxole was converted into a safrole derivative through a one‐pot process involving two consecutive irradiations, at 366 nm for the photocatalyzed alkylation at position 2 and at 310 nm for the alkylation at position 5.     

烷基锡化合物在HY沸石超笼表面的接枝反应研究

在高真空系统中研究了HY沸石分子筛与SnMe₄、SnEt₄、SnPr₄和SnBu₄的反应，用元素分析、ICP、GC、XRD、FTIR、TG、DRS、TPR、BET及烷烃和芳烃的脉冲吸附等方法表征了产物的组成、结构和性质。结果表明，HY沸石分子筛超笼羟基与SnMe₄、SnEt₄、SnPr₄和SnBu₄的反应温度分别为：183K、243K、273K和333K，生成组成为(≡Si-O)SnR₃的表面单接枝物种。表面接枝烷基锡碎片后，HY沸石的孔口尺寸变小，吸附行为发生显著变化。     

Microwave synthesis,characterization and catalytic properties of titanium-incorporated ZSM-5 zeolite

Titanium-incorporated ZSM-5 zeolites (Si/Al = 50–200 and Si/Ti = 70) were successfully synthesized in a one-step sol-gel process under microwave irradiation. The characteristics of Ti-ZSM-5 zeolites were investigated using X-ray power diffraction, UV/Vis-DRS, FT-IR spectroscopy and solid-state ²⁷Al-NMR to monitor the physico-chemical properties. Simultaneously, the acidic properties were characterized by the NH₃-TPD profile. The characterization results revealed that the Ti⁴⁺ and Al³⁺ ions were well incorporated into the framework of Ti-ZSM-5 zeolite. The prepared zeolite was moderately active but selective in the dehydration of methanol to dimethyl ether.     

壳聚糖硫酸盐催化合成柠檬酸三丁酯

柠檬酸三丁酯(简称TBC)是一种无毒高效的优质增塑剂,它具有相容性好、增塑效率高、无毒、挥发性小且耐寒性、耐光性、耐水性好等优点,已被美国食品与药品管理局(FDA)认为是最安全的增塑剂之一。本文以柠檬酸、正丁醇为原料,自制的壳聚糖硫酸盐为催化剂合成柠檬酸三丁酯。探讨了酸醇的物质的量比、催化剂用量、反应时间、反应温度等因素对反应的影响。实验表明,当酸醇的物质的量比为1∶10、催化剂为柠檬酸用量21 4%、反应时间为8h、反应温度为120℃时,酯化率可达97 26%,并且催化剂可重复使用多次。1　实验部分1 1　试剂与仪器WAY 1S…     

Alkylation of α-methylnaphthalene with long-chain olefins catalyzed by rare earth lanthanum modified HY zeolite

Modified HY zeolites impregnated with an optimum amount of lanthanum was found to be an effective catalyst for the clean alkylation of α-methylnaphthalene with long-chain olefins. It was found that Brönsted acid was the main catalytically active center and that the reaction required an optimal concentration of acidic sites. The deactivated LaHY zeolite catalyst can be regenerated by temperature-programmed calcination.     

复合分子筛催化微晶纤维素水解

采用水热晶化法制备了HY/ZSM-5复合分子筛。通过XRD、SEM、N2-吸附脱附、NH3-TPD及吡啶吸附红外光谱等手段表征催化剂的结构和性质。结果表明,HY与HZSM-5复合后HY型分子筛完全被HZSM-5紧密包裹,形成致密的核壳结构。与机械混合物相比,复合分子筛微孔比表面积及孔体积均有所减少,总酸量略高,弱酸量小,而强酸量大,Br9nsted酸量与之相似,而Lewis酸量有所减少。将所制备的HY/ZSM-5复合分子筛催化剂应用于以离子液体氯化1-乙基-3-甲基咪唑鎓([Emim]Cl)为溶剂的纤维素水解反应中,与HY催化的纤维素水解相比,HY/ZSM-5催化纤维素水解反应获得的最佳葡萄糖收率由28.04%提高到38.78%,葡萄糖选择性由28.91%提高至48.29%。     

改性Y型分子筛对硫醇硫醚的吸附脱除研究

通过液相离子交换法制备了Cu(I)Y、Ni Y、Ce Y分子筛,以XRD、低温N2吸附-脱附、NH3-TPD、吡啶红外Py-FTIR等方法对其进行物性表征。利用固定床技术、WK-2D微库伦仪及硫化学发光检测GC-SCD色谱评价了改性分子筛对于硫含量300μg/g模拟油(含硫化合物二丙硫醚、环己硫醇和1-庚硫醇与壬烷配制)及HDS汽油的吸附脱硫性能。结果表明,吸附剂对模拟油和HDS燃料油品中硫醇硫醚具有吸附效果,且改性后的分子筛在吸附脱硫过程中,强的B酸对于吸附脱硫有负作用,会使油品中硫醇硫醚发生催化反应,聚合的大分子硫化物遮盖及阻塞吸附活性位点,从而使吸附剂不能够完全地吸附硫化物,造成吸附硫容较小,而弱L酸无催化活性对吸附脱硫有正面影响。     

NiSO4／HY催化剂上丙烯齐聚反应研究

本文考察了ＮｉＳＯ_４／ＨＹ催化剂用于丙烯齐聚反应的催化性能，研究了镍含量、镍盐、焙烧温度以及反应条件对催化活性和选择性的影响，随镍含量增加，反应活性及二聚选择性都升高，镍含量为９一２０ｗｔ％时活性达最好，液体收率达９５ｗｔ％，随焙烧温度升高，二聚选择性不断升高。催化活性则在８２３Ｋ时有最大值。用吸附指示剂法测定了样品的酸分布，ＣＯ－ＴＰＤ法测定了暴露的Ｎｉ中心量，ＸＲＤ法测定了ＮｉＳＯ_４在ＨＹ上的分散阈值，讨论了它们与丙烯齐聚活性的关联。     

BY分子筛的合成、表征及其裂化性能考察

采用水热晶化法合成了含杂原子硼的Y型分子筛,利用MAS NMR、XRD、IR等表征方法,证明了硼进入Y型分子筛的骨架中。利用吡啶吸附红外光谱、轻油微反装置分别测定了Y和BY分子筛的表面酸性及其裂化性能。结果表明,硼的引入增加了Y分子筛的B酸中心数目以及裂化和氢转移反应活性,导致裂化汽油中的烯烃明显降低,芳烃随之增加。