丙烷选择氧化制丙烯酸MoVTeNbO催化剂研究进展

对丙烷选择氧化制丙烯酸的3类催化剂进行了分析,指出了它们未来的研究方向,重点对MoVTeNbO催化剂上丙烷氧化反应机理进行了探讨,总结了人们对该催化剂晶相结构认识的差异,复合金属氧化物催化剂研究的重点是准确掌握催化剂结构．性能关系,实现具有特定晶相结构催化剂的重现性。     

丙烷在复合金属氧化物上的选择氧化与氨氧化

综述了复合金属氧化物催化剂（CMO）上丙烷选择氧化制取丙烯酸和氨氧化制取丙烯腈的反应过程及水和氨在其中的作用,介绍了丙烷选择氧化和氨氧化过程中具有活性和选择性的晶相性质,并对今后的研究进行了展望。     

丙烷氨氧化制丙烯腈的催化剂研究

运用催化剂设计的集团结构适应理论,给出了丙烷氨氧化反应制丙烯腈的具体反应历程,研制了一系列丙烷氨氧化丙烯腈的催化剂,并详细考察了催化剂中Ｖ,Ｓｂ,Ｗ,Ｓｎ,Ｐ,Ｋ,Ｃｒ,Ｍｏ等组分对反应结果的影响。     

丙烷氨氧化制丙烯腈工艺以及催化剂研究进展

由于原料丙烯的短缺以及对丙烯腈需求的不断增加,本文提出一种以丙烷为原料的丙烯腈生产路线,并主要介绍了丙烷氨氧化反应的两种工艺和几种有发展前景的催化剂,为丙烯腈生产提供了一条具有经济吸引力的新路线。     

丙烷氧化制丙烯酸催化剂研究进展

丙烯酸是一种简单的不饱和羧酸,是现代化工重要的基础原料之一,也是常见的中间体,其需求量呈逐年增加的趋势.丙烯酸具有双键和羧酸的结构,因而酸性强,其化学性质活泼.目前,制备丙烯酸有丙烯氧化法和丙烷氧化法两种方法,前者已实现工业生产,丙烷氧化法目前在实验室研发阶段,较丙烯而言,丙烷具有来源稳定、廉价易得等优势,具有很大的研...     

丙烷直接氧化制丙烯酸的研究进展及展望

丙烷直接氧化制丙烯酸是近年来烃类催化氧化的热点课题。MoVTeNbOx复合金属氧化物催化剂被认为是目前对于该反应催化性能最好的一类催化剂。作者针对在丙烷直接氧化制丙烯酸领域中影响MoVTeNbOx系列金属氧化物催化性能的因素及将来可能开发的烃类选择氧化反应新工艺两方面进行综述。     

丙烷氨氧化制丙烯腈催化剂设计进展

丙烷氨氧化制丙烯腈反应工艺是潜在的具有较大经济效益的丙烯腈生产路线。介绍了丙烷氨氧化制丙烯腈催化剂的设计、催化反应机理、典型催化剂组成和结构的研究进展。     

综述与展望 丙烷直接氨氧化制丙烯腈生产工艺及催化剂研究进展

概述丙烯腈的生产方法及特点,分析丙烷直接氨氧化生产丙烯腈的工艺特点和优势,对丙烷直接制备丙烯腈的催化剂体系Sb-V-O催化剂、Mo-V-Te-Nb-O催化剂、钒-铝氮氧化物及分子筛类催化剂等进行介绍,并建议我国尽快实现以丙烷为原料生产丙烯腈。     

MoVTeNbO_x催化剂焙烧条件对丙烷氧化制丙烯酸的影响

制备了Mo1V0.25Te0.13Nb0.12Ox催化剂,研究了焙烧条件（焙烧方式、焙烧气氛和焙烧温度）对该催化剂在丙烷选择氧化制丙烯酸反应中的影响。结果表明,两段间歇式焙烧要优于一段式连续焙烧所得催化剂的催化效果,适宜的预焙烧温度既有利于脱除挥发性物质和化学结合水,又能避免活性组分氧化生成不利的晶相;在惰性气氛中焙烧所得催化剂的催化效果要优于在弱氧化性气氛中焙烧,丙烷转化率和丙烯酸收率随着焙烧温度的升高先增加后减小,在600 ℃时达到最大值。     

丙烷选择氧化制丙烯酸复合金属氧化物催化剂的研究进展

综述了丙烷选择氧化制丙烯酸的复合金属氧化物催化剂(CM0)研究进展，特别是主要金属元素的作用以及催化剂制备过程中金属原子比、混合方法、干燥方式、焙烧气氛和pH值等因素对CMO催化性能的影响，并指出了今后的研究方向。     

Dual-templating of macroporous multicomponent MoVTeNbO x catalysts for propane ammoxidation to acrylonitrile

Thermally stable ordered porous MoVTeNbO _x phases displaying both macroporous and mesoporous structures were prepared for the first time by a dual-templating approach employing colloidal arrays of polystyrene spheres and non-ionic surfactants. The MoVTeNbO _x phases possessing such dual porosity were obtained after polystyrene spheres and non-ionic surfactants were removed in a low temperature calcination step. These hierarchical MoVTeNbO _x phases displaying bimodal pore structure transformed into macroporous rutile phase possessing nanocrystalline inorganic walls at high temperature. These MoVTeNbO _x rutile phases possessed high surface areas (70 m²/g), desirable pore architectures, robust nanocrystalline inorganic walls, and enhanced thermal stability (up to 600 °C). Although these macroporous MoVTeNbO _x rutile catalysts displayed lower activity in propane ammoxidation and lower acrylonitrile selectivity in propane ammoxidation as compared to the active and selective M1 phase, the novel synthesis method reported in these studies represents a promising general approach to design novel complex mixed metal oxides for a wide range of applications in selective oxidation catalysis.     

Lignocellulosic-derived catalysts for the selective oxidation of propane

The formation of dispersed VPO phases on a lignocellulosic-based activated carbon results in a catalyst that is selective for the partial oxidation of propane, and stable under oxidizing conditions. The use of a stable activated carbon as a catalytic support for active VOx species during the partial oxidation of propane is described for the first time.     

丙烷氨氧化制丙烯腈催化剂及工艺进展

丙烷氨氧化制丙烯腈是一种具经济吸引力的潜在丙烯腈生产路线。对近年来这方面的催化剂开发、反应机理、技术经济性和发展趋势作了评述。通过比较发现,钒铝氧氮催化剂在丙烷氨氧化体系中具有较钒钼和钒锑混合氧化物催化剂更高的空间收率。     

Selective ammoxidation of propane over multicomponent oxide catalysts

The ammoxidation of propane to acrylonitrile was investigated over various multicomponent mixed oxidecatalysts. Bi₃GaMo₂ oxide, Bi_0.85V_0.55Mo_0.45 oxide and Bi₂TiMo oxide showed a good selectivity to acrylonitrile. The catalytic performance was strongly dependent on the components constituting the oxides due to the concentration of defects, the nature of the component and the mixed oxide phases. The effect of support type on the catalytic performance of Bi_0.85V_0.55Mo_0.45 oxide showed that selectivity to acrylonitrile decreased in the order silica > alumina > magnesia. The catalytic performance of Bio_0.85V_0.55Mo_0.45 oxide was improved by the addition of a small amount of a component such as magnesium, calcium and tellurium. The catalytic performance of Bi₃GaMo₂, oxide catalyst, however, decreased significantly with the addition of a smallamount of alkali metal (Li, Na, K, Cs).     

Complex metal-oxide catalysts for selective oxidation of propane and derivatives: I. Catalysts preparation and application in propane selective oxidation to acrylic acid

Several parameters involved in preparing the complex metal-oxide (CMO) catalysts (M_aV_bTe_cNb_dO_n, M: Mo and W) for the selective oxidation of propane to acrylic acid (AA) were investigated and discussed. These include the role each metal element plays and the effects on the performance of the catalysts exerted by the proper metal ratio, as well as various preparation methods, such as the mixing of starting chemicals to form an aqueous precursor mixture, the solvent removal, and the proper calcination atmosphere and gas flow. It was found that each metal element plays a critical role and while an appropriate MoVTeNb metal ratio is critical to the formation of an effective catalyst, each and every step of the preparation methods also have profound effects on the structures and performance of the resulting catalysts. The preferred preparation method for an effective MoVTeNb oxide catalyst includes the intimate mixing of all starting chemicals to form a precursor solution, drying via rotavap for solvent removal followed by calcination under a non-flow inert atmosphere. Using this preferred preparation method, effective complex metal-oxide catalysts can be prepared which affords up to 73% propane conversion and 42% one-pass yield to acrylic acid, while undesirable preparation methods, in contrast, lead to very ineffective catalysts of the identical composition.     

Formation of active phases in MoVTeNb oxide catalysts for ammoxidation of propane

The method of drying, heat evaporation or spray drying, of the aqueous suspension of starting chemicals has a pronounced effect on the phase composition of the final MoVTeNb catalyst, which ultimately influences the catalytic properties in propane ammoxidation reaction. The sample synthesized by spray drying is active and selective; it contains two main crystalline phases, orthorhombic M1 and hexagonal M2. The activity of the sample prepared by heat evaporation is low. This sample does not contain the active M1 phase and consists of hexagonal M2, TeMo₅O₁₆, and Mo_5−x(V/Nb)_xO₁₄ phases. The different mechanisms of phase composition formation in the samples synthesized by heat evaporation or spray drying arise from the different chemical nature of corresponding solid precursors.     

丙烷选择氧化金属氧化物催化剂的研究进展

综述了多组分金属氧化物催化剂对非均相选择氧化反应的一般特性，包括酸特性和氧物种的性质及在催化反应中结构／晶相状态的变化。并对丙烷选择氧化的机理及Mo—V—Sb(Te)—Nb—O多组分混合金属氧化物的晶相结构及性能进行了总结。