ZSM-5/Y复合分子筛的酸性及其重油催化裂化性能

 ZSM-5/Y是本研究组合成的一种新型复合分子筛材料. 用“两次交换,两次焙烧”和磷 酸氢二铵浸渍方法对该复合分子筛材料进行了改性,采用红外光谱表征了复合分子筛的酸性,研究了磷改性对复合分子筛样品羟基区谱学性质的影响,并与相应的机械混合分子筛样品进 行了对比. 红外光谱数据表明,磷改性后复合分子筛的B酸(主要是中强酸)增加,而机械混合分子筛在各个酸强度区域的B酸量和L酸量都减少. 以新疆重油为原料考察了改性后复合分子 筛样品和机械混合分子筛样品的催化裂化性能. 与相应的机械混合分子筛催化剂相比,磷改 性复合分子筛催化剂具有较高的柴油选择性,其柴油产率增加了4.1个百分点,柴汽比增加了0.11,总轻油产率与机械混合分子筛相当. 用气体产物中的CMR(裂化机理比)和C3/C4比 值分析了复合分子筛的催化性能与其聚集体结构的关系.     

SAPO-11/Beta复合分子筛的合成及其异构化性能研究

以Beta分子筛为硅源通过水热合成法合成了SAPO-11/Beta复合分子筛,采用X射线衍射、N2物理吸脱附、扫描电镜、透视电镜-能谱分析、固体核磁及吡啶红外等方法对单分子筛、复合分子筛和机械混合分子筛的物化性质进行了表征.以正十二烷为模型化合物,在固定床反应器上考察了铂负载型分子筛催化剂的异构化性能.结果表明,复合分子筛的物理化学性质明显不同于单分子筛和机械混合分子筛,其呈现核壳结构,SAPO-11和Beta间存在化学作用,使得复合分子筛具有适宜的B酸分布.在正十二烷异构化反应中,复合分子筛催化剂的异构化性能优于单分子筛催化剂和机械混合分子筛催化剂,多支链异构体收率高.     

ZSM-5/ZSM-57复合分子筛催化剂上混合C4烃的催化转化反应

以ZSM-5/ZSM-57复合分子筛为催化剂, 考察了其对混合C4烃催化转化的反应性能. 采用氨程序升温脱附(NH3-TPD)和吡啶吸附傅立叶变换红外(FT-IR)光谱技术表征复合分子筛的酸性质. 结果表明, 当复合分子筛中ZSM-5的含量较低时, 比ZSM-5具有更高的催化活性及乙烯和丙烯选择性, 这是因为此时复合分子筛酸强度较高、酸量较多, 且小孔ZSM-57有利于乙烯和丙烯的择形反应. 而当复合分子筛中ZSM-5的含量较高时, 具有较高的苯和甲苯选择性, 其原因可能是其孔结构及共晶生长时的结构匹配性对芳构化反应有利.     

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%。     

ZSM-5／MOR复合分子筛催化剂对混合C4烃转化反应的催化性能

以ZSM-5/丝光沸石(MOR)复合分子筛为催化剂,对混合C4烃的催化转化反应进行了评价,并采用程序升温脱附和原位红外光谱技术对ZSM-5/MOR的酸性进行了表征. 结果表明,与ZSM-5相比, MOR具有很低的催化活性,但ZSM-5/MOR复合分子筛具有较高的催化活性,随着ZSM-5/MOR复合分子筛中ZSM-5含量的增加, C4烃转化率稍有升高;在C4烃转化率大致相同的情况下,乙烯和丙烯的总选择性比较接近,但苯和甲苯的总收率却快速升高. 随着ZSM-5/MOR复合分子筛中ZSM-5含量的增加,弱酸和中强酸的酸量逐渐减少,强酸的酸量有所增加. 由于ZSM-5/MOR复合分子筛中MOR对ZSM-5起到分散作用而产生更多的L酸中心,且此L酸中心处于分子筛的外表面而具有较高的能量,导致苯和甲苯的总收率升高.     

高效ZSM-5-L二元复合分子筛的合成及正戊烷芳构化性能

通过优化水热陈化条件制备纳米L沸石,再采用水热合成结合原位二次晶化法,合成具有微-介复合孔结构的高效ZSM-5-L二元复合分子筛.考察了体系pH、二次晶化温度等因素对ZSM-5-L复合分子筛合成的影响,采用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和傅里叶变换红外光谱(FTIR)等技术对复合分子筛进行表征,确定了最佳复合条件:pH=10.5~11.5,晶化温度170℃,晶化时间24 h.ZSM-5-L复合分子筛具有不同于ZSM-5沸石、L沸石及两者机械混合物的物性特征,且具有微-介复合孔结构.以正戊烷催化转化为探针反应,评价了ZSM-5-L复合分子筛轻烃芳构化反应性能.在相同反应条件下,ZSM-5-L复合分子筛具有优于2种单分子筛及二者机械混合物的正戊烷芳构化催化性能.     

MCM-41-HY复合分子筛的合成及其在深度加氢脱硫中的应用

在水热条件下合成了包覆型MCM-41-HY复合分子筛.采用XRD、N2气吸附和SEM等方法对其进行了表征.结果表明,MCM-41-HY复合分子筛和MCM-41与H型Y沸石(HY)的机械混合物明显不同,在复合分子筛MCM-41-HY中,中孔相MCM-41附晶生长在HY沸石上,将HY包覆起来.以二苯并噻吩为模型化合物,考察了该材料担载NiMo催化剂的加氢脱硫活性.结果表明,MCM-41-HY复合分子筛与MCM-41和HY的机械混合物担载NiMo催化剂的加氢脱硫(HDS)活性相当,但MCM-41-HY复合分子筛担载NiMo催化剂的裂化活性较低.其裂化活性不同的原因在于其载体孔道结构和酸性位的分布不同.     

Cu(Ⅰ)Y分子筛表面酸性对其吸附脱硫性能的影响

用固相离子交换(SSIE)和液相离子交换(LPIE)法制备了不同离子交换度的Cu(Ⅰ)Y分子筛,采用吡啶吸附红外光谱(Py-IR)表征了分子筛的表面酸性,并用固定床吸附穿透实验评价了分子筛的吸附脱硫性能.结果表明,不同的离子交换法改性后,Cu(Ⅰ)Y分子筛仍然保持了完整的Y型分子筛结构.Cu+的交换量和表面酸性的分布显著地影响分子筛的吸附脱硫性能,固相离子交换后随离子交换度的增加,分子筛表面Br(o)nsted (B)酸逐渐转化为Lewis (L)酸,吸附性能增强.对不同离子交换法制备的Cu(Ⅰ)Y分子筛吸附脱硫性能与表面酸性关联后,发现分子筛表面B酸量减少,提高了分子筛的吸附脱硫活性.     

Cu(I)Y分子筛表面酸性对其吸附脱硫性能的影响

用固相离子交换(SSIE)和液相离子交换(LPIE)法制备了不同离子交换度的Cu(I)Y分子筛, 采用吡啶吸附红外光谱(Py-IR)表征了分子筛的表面酸性, 并用固定床吸附穿透实验评价了分子筛的吸附脱硫性能. 结果表明, 不同的离子交换法改性后, Cu(I)Y分子筛仍然保持了完整的Y型分子筛结构. Cu⁺的交换量和表面酸性的分布显著地影响分子筛的吸附脱硫性能, 固相离子交换后随离子交换度的增加, 分子筛表面Brönsted (B)酸逐渐转化为Lewis (L)酸, 吸附性能增强. 对不同离子交换法制备的Cu(I)Y分子筛吸附脱硫性能与表面酸性关联后, 发现分子筛表面B酸量减少, 提高了分子筛的吸附脱硫活性.     

重质馏分油加氢处理催化剂用Y型分子筛-钛硅氧化物复合载体研究

采用溶胶－凝胶结合CO₂超临界干燥的方法制备了钛硅复合氧化物（CTS）载体基质材料。以不同方法将Y型分子筛与CTS混合制得Y/CTS复合载体,以Ni、W为活性金属组分,采用等体积溶液浸渍法制备了加氢处理催化剂。考察了Y型分子筛与CTS的复合方式及加入量对催化剂加氢精制性能的影响,进而研究了P改性对Y/CTS结构及酸性的影响。结果表明,Y型分子筛的加入提高了CTS复合氧化物的酸性和比表面积,适当的分子筛加入量没有破坏CTS原有的结构。当Y型分子筛的加入量大于20%,Y/CTS的总酸量高于CTS,尤其是B酸量提高幅度较大, B酸强度也明显增加;Y/CTS载体中加入P以后,载体的总酸量增加,L酸的比例提高。以胜利焦化蜡油为原料,对催化剂的加氢反应性能评价结果表明,Y型分子筛的加入以及P对Y/CTS的改性,能够在一定程度上提高催化剂的加氢脱硫和加氢脱氮活性。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.