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1.
离子液体中异丁烷与丁烯的烷基化反应   总被引:1,自引:0,他引:1  
合成出一系列具有不同阴离子或阳离子结构的离子液体 ,并在高压釜中评价了这些离子液体对异丁烷与丁烯烷基化反应的催化效果以及相关反应条件的影响。实验结果表明 ,由无水三氯化铝参与合成的离子液体催化性能较好 ,其活性来源于 [Al2 Cl7]-。阳离子的类型影响产物的选择性 ,反应过程中烷基化油容易与离子液体分离。当烷、烯体积比为 4 0 ,反应温度为 6 5℃及反应时间为 2min时 ,烷基化油收率达到进料丁烯体积的 15 6 % ,其中C8组分的含量可以达到 5 7%以上 ,在催化反应过程中 ,离子液体可以重复使用。  相似文献   

2.
离子液体中异丁烷与丁烯的烷基化反应   总被引:5,自引:0,他引:5  
合成出一系列具有不同阴离子或阳离子结构的离子液体,并在高压釜中评价了这些离子液体对异丁烷与丁烯烷基化反应的催化效果以及相关反应条件的影响。实验结果表明,由无水三氯化铝参与合成的离子液体催化性能较好,其活性来源于[Al2C17]-。阳离子的类型影响产物的选择性,反应过程中烷基化油容易与离子液体分离。当烷、烯体积比为40,反应温度为65℃及反应时间为2min时,烷基化油收率达到进料丁烯体积的156%,其中C8组分的含量可以达到57%以上,在催化反应过程中,离子液体可以重复使用。  相似文献   

3.
向2AlCl3-Et3NHCl离子液体中分别加入二硫化碳、丁基硫醇、二甲基硫醚和丙酮,考察了其对离子液体催化异丁烷/2-丁烯烷基化性能的影响.在相同反应条件下,以二硫化碳和丁基硫醇改性的离子液体的催化性能优于未改性离子液体:烷基化产品中的C8组分含量由49.7%分别提高到68.6%和79.2%,TMP(三甲基戊烷)/DMH(二甲基己烷)从0.92分别提高到5.81和4.07.采用乙腈探针红外光谱法测定了离子液体酸性,发现改性后离子液体的路易斯酸强度均有所降低,不同助剂对离子液体的路易斯酸强度的影响也有差别.2AlCl3-Et3NHCl离子液体改性前后的27Al核磁共振波谱表明:Al2Cl7-量的下降导致了改性离子液体酸强度的减弱,其催化性能提高可以归因于加入的助剂在离子液体中形成的新配合物.  相似文献   

4.
基于离子液体烷基化工艺特点,提出一种液-液旋流反应器,利用旋流反应器的特殊结构实现反应及产物初级分离过程的一体化,提高产量的同时可降低副反应的发生.利用CFD-PBM耦合模型,对无反应条件下旋流反应器反应腔内分散相液滴尺寸分布及两相相接触界面面积进行研究,研究了操作参数(入口总流量、进料比、溢流比)对反应腔内分散相液滴...  相似文献   

5.
室温离子液体及其在绿色化学中的应用   总被引:5,自引:0,他引:5  
综述了国内外对室温离子液体的研究状况。对室温离子液体作为高效绿色溶剂,广泛应用于油页岩的处理、天然气的净化、核燃料的加工,在有机合成中作为绿色替代溶剂来进行Diels-Alder反应、Friedel-Crafts反应、过渡金属催化反应、镜像选择烷基化等反应中的应用状况及发展前景进行了较为详细的介绍。并且,讨论了室温离子液体组成环境友好催化体系,在替代传统强酸催化剂用于稠环芳烃的烷基化反应、各种醇与乙酸的酯化反应、Beckmann重排反应、芳香族化合物的氢化反应以及聚合反应中,具有反应速度快、转化率高、催化体系可循环使用等优点。  相似文献   

6.
设计了新型迷宫式鼓泡光催化反应器(LBPR),以30~40目活性碳为载体,采用溶胶-凝胶法制备了负载型TiO2薄膜颗粒光催化剂,对含甲基橙废水进行光催化降解.考察了反应器内折流板数量与出水液面高度等结构参数及液速对有机物降解性能的影响.结果表明:当折流板为12块,液面高度为4 cm时,在液量0.011 1 m3/h、催化剂4.8 g/L的完全流化的操作条件下反应1.5 h,降解率达到100%.此外还考察了催化剂带出量及其在反应器中的停留时间随液体流量以及折流板数的变化关系.  相似文献   

7.
通过烷基化反应和简单的一锅法将醇胺离子液体(TEA)嫁接到氯甲基聚苯乙烯(PS-Cl)微球上,将形成的嫁接型离子液体催化剂(PS-[TEA]I)用于催化CO2和环氧化物生成环状碳酸酯的反应. 采用傅里叶变换红外光谱(FT-IR)和扫描电子显微镜(SEM)表征催化剂的结构和形貌,采用X射线光电子能谱(XPS)、元素分析(EA)和热重分析(TGA)研究了醇胺离子液体的嫁接量和热稳定性. 在环加成反应中,该催化剂无需溶剂和助催化剂,在催化剂用量为0.10 g、温度为120 ℃、CO2压力为2 MPa以及反应时间为4 h的条件下,碳酸丙烯脂(PC)的产率达到93.30%,并且反应后容易分离,可重复使用. 最后提出了羟基形成的氢键可激活环氧化物和I-亲核进攻促进开环的反应机理.  相似文献   

8.
利用改性的巯基硅胶与乙烯基咪唑类酸性离子液体发生自由基聚合反应制备固载酸性离子液体催化剂[(CH2)3SO3HVIm]HSO4/硅胶.考察聚合温度、离子液体单体量和聚合反应时间的变化对所制备催化剂催化性能的影响,并用红外光谱(FTIR)、热重/差示扫描量热分析(TG/DSC)等对催化剂进行表征.结果表明:聚合温度60 ℃、每g巯基硅胶载体固载离子液体单体10 mmol、聚合反应时间30h时合成的催化剂催化效果最佳.同时,将最佳条件下制备的催化剂应用于一系列羧酸与醇的酯化反应,酯收率大于87%.  相似文献   

9.
离子液体超酸催化合成乙酸乙酯   总被引:15,自引:0,他引:15  
研究了在具有Lewis酸性的离子液体体系中进行的乙酸乙酯反应。以氯化 1-甲基 - 3-乙基咪唑 (ME IC) ,氯化 1-丁基吡啶 (BPC) ,氯化 1-甲基 - 3-丁基咪唑 (MBIC)及盐酸三甲胺 (TMHC)季铵盐分别与AlCl3 原位合成法制备离子液体催化体系。结果表明 :以上各种离子液体均有很高的催化活性 ,反应转化率在较短的时间内达到 92 %。其中TMHC -AlCl3 离子液体反应转化率为 95 %。与H2 SO4或固体超酸相比 ,催化活性显著提高 ,生成乙酸乙酯不溶于离子液体 ,因而易于分离 ,催化剂可重复使用  相似文献   

10.
采用盐酸三乙胺(Et3NHCl)和无水AlCl3按不同的物质的量的比合成离子液体,并评价其对模型汽油噻吩硫的催化烷基化脱除效果.实验结果表明:选用Et3NHCl与无水AlCl的摩尔比为1∶2的离子液体进行烷基化脱硫实验,当反应时间时间为40 min,温度为40℃,萃取剂油比为1:40时,脱硫率可达到90%以上,还采用红外探针分子表征不同摩尔比的离子液体的酸性.离子液体应用结果表明,对商品汽油的脱硫率可达到在80%以上而辛烷值仅从92.7下降到91.0.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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