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1.
《Catalysis Reviews》2013,55(2):175-256
Asymmetric heterogeneous catalysis is a vivid branch of catalysis, remaining, however, largely a domain of organic chemists. The view towards asymmetric heterogeneous catalysis adopted in this review is mainly from catalytic science and engineering. Not only reaction mechanisms, but also catalytic properties, kinetic regularities, as well as chemical engineering aspects, are covered with the main focus on recent developments.  相似文献   

2.
Sulfate radical-advanced oxidation processes (SR-AOPs) are promising technologies for organic pollutants elimination. Heterogeneous metal-based catalysis has been widely studied and applied to activate peroxymonosulfate (PMS) for producing sulfate radicals. Developing highly efficient catalysts is crucial for future extensive use. Importantly, the catalytic activity is mainly determined by mass and electron transfer. This paper aims to overview the recent enhancement strategies for developing heterogeneous metal-based catalysts as effective PMS activators. The main strategies, including surface engineering, structural engineering, electronic modulation, external energy assistance, and membrane filtration enhancement, are summarized. The potential mechanisms for improving catalytic activity are also introduced. Finally, the challenges and future research prospects of heterogenous metal-based catalysis in SR-AOPs are proposed. This work is hoped to guide the rational design of highly efficient heterogenous catalysts in SR-AOPs.  相似文献   

3.
在碳达峰、碳中和的目标背景下,生物柴油被认为是替代化石燃料最有前途的新型能源之一。作为新型的加热方式,微波强化技术克服了传统加热方式下受热不均等缺点,在与不同催化体系偶联的过程中显著促进了酯交换反应的效率,较大幅度地提高了生物柴油的产率。本文归纳了微波技术强化酯交换反应制备生物柴油的优势,介绍了微波强化技术偶联均相催化、非均相催化、离子液体催化以及酶催化技术在生物柴油制备领域的研究进展,阐述了微波强化技术偶联各催化体系的利弊。从催化效率和环保等方面考虑,微波强化偶联非均相催化和酶催化具有更优的研究前景。最后,就该领域的研究方向提出几点展望与建议。  相似文献   

4.
Catalytic reactors based on porous ceramic membranes   总被引:4,自引:0,他引:4  
J. Coronas  J. Santamarí  a 《Catalysis Today》1999,51(3-4):377-389
This overview discusses some of the developments and outstanding opportunities in the field of catalytic reactors based on porous ceramic membranes, both inert and catalytic. This is an emerging area, where inputs from heterogeneous catalysis, material science and reactor engineering are playing the key roles. Rather than attempting a thorough review of the relevant literature, this work deals with some general concepts and then concentrates on a few selected examples that illustrate the application of membrane reactors.  相似文献   

5.
The possibilities of molecular design in the development of new catalysts and catalytic technologies are discussed with the data obtained recently at the Boreskov Institute of Catalysis as particular examples. Examples from the following areas are presented: homogeneous catalysis with metal complexes, heterogeneous catalysis with anchored metal complexes, heterogeneous catalysis with catalysts prepared via anchored metal complexes and organometallics, catalysis of olefin polymerization, catalysis by metals, catalysis by oxides, catalysis by zeolites, catalysis by heteropolyacids, catalysis with nontraditional oxidants and biomimetic catalysis.  相似文献   

6.
近年来,中空纳米材料以其独特的结构和优异的性能,在许多学科研究中引起了广泛的关注。中空纳米结构具有高的比表面积、明确的活性中心、有限的孔隙空间和可调的传质速率,可在光催化、电催化、均相、非均相等多种催化反应中作为催化剂、载体和反应器。基于最先进的合成方法和表征技术,研究者们致力于中空纳米材料有目的功能化,以用于研究催化机理和复杂的催化反应。本文综述了如何构筑纳米反应器以实现更高活性和选择性的催化反应。尤其是关于中空纳米材料的表面功能化策略,具体包括形貌和组成改性、包封、多壳层构筑、单原子位点设计、表面分子工程化等五大部分,为中空纳米材料功能化变为有效催化剂的合理设计和开发提供了理想的模型。  相似文献   

7.
环境友好的超临界多相催化反应研究进展   总被引:8,自引:1,他引:7  
在传统的多相催化反应中引入惰性超临界流体的超临界多相催化反应可以改善反应过程或减少环境污染.综述了超临界多相催化反应的特点,并着重从催化超临界水氧化反应、超临界相转移催化反应、超临界酶催化反应等3个方面详细论述了超临界多相催化反应的研究进展.最后对今后的发展方向提出了看法.  相似文献   

8.
Over the last decade, transition metal nanoparticles have attracted much attention owing to their unique properties, different to their bulk counterparts, which facilitate their application in different fields from materials science to engineering. Of particular interest, the use of transition metal nanoparticles in catalysis has brought transcendent efficiency in terms of activity, selectivity and lifetime to heterogeneous catalysis. In this account, we summarize the recent developments in the synthesis routes and the catalytic performance of transition metal nanoparticles tested in the hydrogen generation from the hydrolysis of ammonia-borane, which has been considered as one of the attractive materials for the efficient storage of hydrogen that is still one of the key issues in the “Hydrogen Economy”.  相似文献   

9.
A variety of metal oxides catalysts are used in heterogeneous catalysis for chemical processes and have now been developed for their catalytic performance and durability. The heterogeneous catalysis is the most important technology in chemical industry as well as other environmental, energy applications, etc. This review examines recent advances at the preparation and applications of metal oxide particles, especially pertaining to catalytic enhancements for current and future chemical process such as Fischer–Tropsch process, alkylation, and transesterification and environmental applications such as the oxidation of volatile organic compounds and the reduction of NOx.  相似文献   

10.
组合化学在多相催化领域中的应用   总被引:6,自引:0,他引:6  
本文系统综述了新近兴起的技术——组合化学在多相催化领域中的研究进展。通过对组合催化研究的两个关键因素催化剂库合成及催化剂高通量筛选技术的评价分析认为,在对已有的催化体系和催化剂优化的同时,如何高效研制新催化材料及开发新筛选检测技术,是组合催化研究的主导思想,对此的深刻理解和运用,将增强实验室的创新能力。  相似文献   

11.
12.
伯醇催化氧化制羧基化合物是有机合成中一类极为重要的转化过程,具有广泛的应用场景。对于多相催化系统,高效催化剂的制备一直是研究的热点和难点。本文对近年来涉及多相催化氧化伯醇制备羧基化合物的文献进行了全面的梳理。从单金属和双金属活性组分,以及是否采用载体等角度,系统评估了伯醇氧化多相催化剂的发展现状和趋势,并展望了多相催化在工业应用中的发展前景和挑战。  相似文献   

13.
Milestones and perspectives in electrochemically promoted catalysis   总被引:1,自引:0,他引:1  
Electrochemical promotion of catalysis is a unique tool for the in situ tuning of catalytic activity of electronically conductive metals or metal oxides in contact with solid electrolytes. The importance of electrochemical promotion to heterogeneous catalysis, surface science and electrochemistry research for the investigation of spillover phenomena and metal–support interactions is well recognized. The unlimited applications of the phenomenon, in terms of catalysts, solid electrolytes or catalytic reactions selection, has been proven through numerous laboratory investigations. Though the molecular origin of electrochemical promotion has been revealed, using a variety of experimental techniques and theoretical calculations, there is still a shortage on the practical level. However, in the last decade, spectacular progress has been made in the development of effective, low cost electropromoted catalysts and reactors. The major technological advances and milestones towards the practical utilization of electrochemical promotion are surveyed in view of electrocatalysts development and system/reactor engineering.  相似文献   

14.
Esterification is an important process in the food industry and can be carried out via homogeneous or heterogeneous catalysis. The homogeneous catalyst, despite providing high conversion, can cause corrosion in reactors, which is not observed with the use of heterogeneous catalysts. However, some of these catalysts require a high process temperature and may lose their catalytic activity with reuse. Thus, catalytic membranes have been proposed as a promising alternative. The combination of cataly...  相似文献   

15.
Heterogeneous catalysis is a key pillar of the global industrial chemical and petrochemical sector, and 85% of all chemical products are produced with at least one catalytic step. Indeed, catalysis and catalytic reactors are a critical underpinning science for energy, environmental, and economic security. This paper reviews some future critical directions for research in catalysis science, toward a greener and more sustainable future. We believe that even a relatively mature field as heterogeneous catalysis and nanomaterials can be vitalized and spurred by major discoveries, but an outside-the-box thinking and a focused effort in a large plurality of disciplines is necessary. Thus, critical research needs in several areas, including heterogeneous and homogeneous catalysis, biocatalysis, photocatalysis, electrochemical conversions, and computational catalysis, are reviewed. The research needs of the future lie at the intersection of synthesis of novel nanostructured materials with tunable pore size distribution, controlled porosity, and high surface area; development of new catalytic applications for such materials; and the science of advanced characterization including in situ spatiotemporal analysis. In the area of computational catalysis, we believe that the future lies in the development of hybrid methods (parallel and serial) which can model the typical multiscale phenomena that are typically encountered in protein translocation and signal transduction, charge transport, enzymatic catalysis, surface chemistry, and self-assembly in complex fluids. As we promulgate the new directions to the catalysis fraternity, some prior research areas will unfortunately need to be relegated to obsolescence, to maintain a healthy balance on the research forefront.  相似文献   

16.
Zahmakıran M  Ozkar S 《Nanoscale》2011,3(9):3462-3481
Metal nanoparticles have attracted much attention over the last decade owing to their unique properties, different to their bulk counterparts, which pave the way for their application in different fields from materials science and engineering to biomedical applications. Of particular interest, the use of metal nanoparticles in catalysis has brought superior efficiency in terms of activity, selectivity and lifetime to heterogeneous catalysis. This article reviews the recent developments in the synthesis routes and the catalytic performance of metal nanoparticles depending on the solvent used for various organic and inorganic transformations. Additionally, we also discuss the prevalent complications and their possible solutions plus future prospects in the field of nanocatalysis.  相似文献   

17.
Whereas cooperative effect in catalysis, in which multiple chemical interactions participate cooperatively to achieve significant enhancement in catalytic activity and/or selectivity, is common in enzymatic reactions, it has been sparingly employed in heterogeneous catalytic systems. Here, some recent literature examples of abiotic catalysis, with emphasis on heterogeneous systems, that employ cooperation between acid and base and two metal centers are briefly described to demonstrate the principles involved. Since effective cooperation places strict demand on the positions of the different functional groups, new synthetic methods and strategies are needed to design and construct structures useful for cooperative catalysis. Recent progress in our laboratory in synthesizing new nanocage structures that possess molecular-size cavities, atomic layer thick, porous shells with internal functional groups is described. These recent developments suggest possibilities of new catalytic transformations that have not been attempted before. This is illustrated with two speculative examples utilizing cooperative catalysis: oxidative hydrolytic desulfurization and terminal carbon activation of hydrocarbon molecules.  相似文献   

18.
The term operando was coined at the beginning of this century to gather the growing efforts devoted to establish structure-activity relationships by simultaneously characterizing a catalyst performance and the relevant surface chemistry during genuine catalytic operation. This approach is now widespread and consolidated; it has become an increasingly complex but efficient junction where spectroscopy, materials science, catalysis and engineering meet. While for some characterization techniques kinetically relevant reactor cells with good resolution are recently developing, the knowledge gained with magnetic resonance and X-ray and vibrational spectroscopy studies is already huge and the scope of operando methodology with these techniques is recently expanding from studies with small amounts of powdered solids to more industrially relevant catalytic systems. Engineering catalysis implies larger physical domains, and thus all sort of gradients. Space- and time- resolved multi-technique characterization of both the solid and fluid phases involved in heterogeneous catalytic reactions (including temperature data) is key to map processes from different perspectives, which allows taking into account existing heterogeneities at different scales and facing up- and down-scaling for applications ranging from microstructured reactors to industrial-like macroreactors (operating with shaped catalytic bodies and/or in integral regime). This work reviews how operando methodology is evolving toward engineered reaction systems.  相似文献   

19.
简述了餐饮废油( WCO)转化为生物柴油的反应原理,比较了利用WCO转化制备生物柴油的各种方法,主要有均相转化法(包括酸催化法、碱催化法和酸碱两步催化法)、非均相转化法(包括固体碱催化法、固体酸催化法)、酶催化法、超临界转化法等,分析了不同方法的特点。  相似文献   

20.
This article reviews microwave‐assisted heterogeneous gas‐phase catalysis. To date, this special means of non‐classical energy input by microwave radiation is still a fringe area of catalysis research, and alternative reaction engineering in chemistry and chemical engineering. However, microwave‐assisted heterogeneous gas‐phase catalysis is expected to gain significant popularity in academia and industry in the near future. Experimental set‐ups that have been described in literature are critically reviewed, and concepts for the design of improved experimental set‐ups are provided in this article. Historical developments, current tendencies, and a short introduction to the theory of dielectric heating are discussed.  相似文献   

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