Cr改性USY分子筛提高裂化催化剂的异构化性能

在催化裂化过程中，烷烃分子在酸性催化剂表面进行一系列的反应，其中氢转移反应能导致汽油中的烯烃质量分数降低，而异构化、环化、芳构化反应则改善裂化产品的分布，对提高裂化汽油的辛烷值有明显的效果。为了解决我国裂化汽油中烯烃质量分数过高的问题，目前大多数催化裂化装置都采用了降烯烃裂化催化剂，以氢转移反应活性高的REUSY分子筛作为裂化催化剂的活性组分。但由于REUSY分子筛的异构化活性较低，因此裂化汽油的辛烷值有所下降，需要对裂化汽油进行加氢异构化处理。若直接对裂化催化剂进行改性，提高其异构化反应活性，     

烯烃在催化裂化催化剂上反应机理的初步研究

在自制的微反-色谱装置上，进行了单体烯烃和催化裂化汽油在不同条件下的催化裂化反应实验。对单体烯烃的裂化反应规律和汽油中的烯烃在半再生催化剂和待生催化剂上的催化裂化反应规律进行对比分析。结果表明，单体烯烃反应中，C6及C6以下的烯烃主要发生骨架异构和双键异构反应，氢转移和直接裂化反应发生的较少。C7以上的烯烃95%以上发生转化，高温下直接裂化生成C3、C4，氢转移和异构化比率较大。汽油中的烯烃转化主要集中在C7以上，烯烃之间存在一定的交互作用，单体烯烃的催化裂化反应规律可以初步预测汽油中烯烃的转化。催化剂上的结焦类型对汽油中的烯烃的转化方式没有影响。     

四氢萘在Mo-Ni/USY双功能催化剂上加氢裂化反应动力学的研究

在活性趋于稳定的Mo-Ni／USY双功能催化剂上，利用连续流动微反－色谱装置，进行了四氢萘加氢裂化反应动力学的研究，在320－400℃、4．5－8．5MPa反应条件下，考察其反应产物分布，建立了四氢萘加氢裂化反应动力模型，计算了反应网络中各步的反应速率常数和活化能，并讨论了反应网络的主线和反应条件对主线的影响。结果表明，Mo-Ni／USY双功能催化剂具有较高的裂化和异构化活性，低温、高压有利于加氢、高温、低压有利于裂化和异构。     

多酸基深度加氢脱硫催化剂的原位表征和反应性能

采用浸渍法合成了镍盐复合的磷钨酸(HPW)/纳米晶HZSM-5固体酸催化剂,其在催化裂化(FCC)汽油加氢改质反应中显示出了良好地深度加氢脱硫活性。 原位电子自旋共振和原位吡啶吸附红外光谱表征手段的研究结果表明,纳米晶HZSM-5沸石上Ni(Ⅱ)结合3电子还原态的HPW(Ⅲ)是FCC汽油深度加氢脱硫反应的活性中心。 探讨了多酸基催化剂在FCC汽油深度加氢脱硫反应中活性改善的原因。     

FCC汽油低温改质过程的烯烃转化及催化剂积炭

利用微反-色谱联合实验装置和连续式小型提升管催化裂化实验装置研究了催化裂化汽油低温改质过程中烯烃转化和催化剂积炭的过程和规律。通过对模型化合物和催化裂化汽油改质过程中催化剂活性、催化裂化汽油窄馏分、反应温度、剂油比和反应时间对烯烃转化和催化剂积炭的研究表明，大部分烯烃转化和催化剂积炭的反应发生在油剂接触极短的反应时间内，并随着催化剂活性、反应物活性、剂油比和反应温度的提高而增加。在油剂接触后很长的反应时间内，生焦量、积炭速率和烯烃的转化程度都很小，烯烃转化损失率降低，因此，催化裂化汽油在低温改质的条件下可以通过延长反应时间来提高烯烃的转化率。因此，催化裂化汽油改质的最佳工艺条件为，390℃～440℃，剂油比6，催化剂活性61～65，长反应时间，轻馏分进料。     

焦化汽油加氢异构化的初步考察

我国延迟焦化汽油的辛烷值低,烯烃含量很高(约50%),稳定性极差。采用加氢异构化方法,不仅能大幅度提高汽油的辛烷值,而且还能大大增强汽油的稳定性和改善其它性质。本文初步考察了在219型催化剂存在下,焦化汽油加氢异构化过程的操作变数以及加硫和脱氮对催化剂活性的影响;同时还用正庚烷及其掺合物考察了焦化汽油中存在的芳烃和大量烯烃在加氢异构化过程中的作用。由此确定了催化剂的最佳操作条件,讨论了各种因素对催化剂的加氢与异构化活性的影响以及催化剂的氮中毒问题。     

采用Pd／树脂催化剂的轻汽油临氢醚化反应研究

研究了催化裂化轻汽油临氢醚化工艺,以降低催化裂化汽油的烯烃含量并提高辛烷值,制备了Pd负载D005阳离子交换树脂催化剂,该催化剂具有同时催化二烯烃选择性加氢和步碳烃与甲醇醚化的功能。考察了遗金属负载量和反应择醚收率的影响,在反应温度343K、压力1．5Mpa,n（甲醇）/ n(叔碳烯烃）比＝1．1、n（氢）／n（二烯）比＝2、液时空速3/h的条件下,醚收率达55．32％。2016h的寿命试验表明,该催化剂活性稳定,可以长周期使用。     

在改性纳米ZSM－5上通过异构化和芳构化减少FCC汽油中的烯烃

 用稀土氧化物浸渍改性纳米HZSM-5沸石制备了降低汽油中烯烃催化剂。临氢条件下，在固定床反应器上对催化剂的降低烯烃性能进行了考察。结果表明，催化剂表现出很强的降烯烃能力。改性的纳米ZSM-5沸石催化剂对汽油的降烯烃作用得益于其优异的异构化、芳构化和烷基化性能。在温度370 ℃、压力3 MPa、质量空速3 h-1和氢油比 （v/v）600的反应条件下, FCC汽油（＜70℃馏分）中烯烃含量从65.9%（φ） 降至32.5%（φ），异构烷烃含量从23.3%（φ）增加到44.3%（φ），芳烃和环烷烃部分增加，直链烷烃基本不变，在大量降低烯烃的同时，汽油的辛烷值（RON）不降低。催化剂连续反应1000 h以上，性能稳定。     

环己烷在Pt/HY-A12O3催化剂上加氢转化反应的研究

采用高压微型反应器，在压力为4．0MPa，温度260℃-350℃、氢油比为500：1、空速1．0h^-1条件下，研究了不同酸性载体HY-Al2O3，负载的铂(Pt)催化剂上环己烷的催化反应规律．结果表明，反应温度和载体酸性是影响催化剂异构化活性、裂化活性的两个重要因素，增加反应温度或提高催化剂酸性都会导致催化剂的异构化活性降低、裂化活性增强．当反应温度为290℃，含15％HY的Pt/HY-Al2O3，催化剂的异构化活性最好，异构化产物的选择性为91．6％，环己烷转化率为71．6％．提高催化剂载体中分子筛含量，有利于环己烷开环反应的发生，从产物的分布可以看出，在Pt/HY-Al2O3，催化剂上环己烷的开环过程是首先异构化为甲基环戊烷继而发生开环反应，反应最终达到平衡状态，致使开环产物中nH：3MP：2MP=1：1：2比值不变，开环机理符合β-断裂的正碳离子机理。     

Pt／HZSM—5和Pt／HZSM—11的催化性能和表面性质的研究

本文用浸渍法制得了Pt/HZSM-5和Pt/HZSM-11两种催化剂。以二甲苯异构化为探针反应,研究了它们的催化性能,对其活性,选择性及寿命进行了考察,并与不载Pt的HZSM-5和HZSM-11沸石分子筛作了对比。发现Pt/HZSM-5和Pt/HZSM-11具有良好的二甲苯异构化活性,选择性和稳定性。在反应600小时后,活性仍未下降。本文选用TPD方法研究了载Pt前后样品酸性质的变化。用程序升温还原(TPR)方法研究了负载金属Pt的还原行为,对Pt在催化反应中的作用进行了初步探索,得到了有益的信息。     

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.