Ionic liquids (ILs) offer a wide range of promising applications because of their much enhanced properties. However, further development of such materials depends on the fundamental understanding of their hierarchical structures and behaviors, which requires multiscale strategies to provide coupling among various length scales. In this review, we first introduce the structures and properties of these typical ILs. Then, we introduce the multiscale modeling methods that have been applied to the ILs, covering from molecular scale (QM/MM), to mesoscale (CG, DPD), to macroscale (CFD for unit scale and thermodynamics COSMO-RS model and environmental assessment GD method for process scale). In the following section, we discuss in some detail their applications to the four scales of ILs, including molecular scale structures, mesoscale aggregates and dynamics, and unit scale reactor design and process design and optimization of typical IL applications. Finally, we address the concluding remarks of multiscale strat...

Multiscale Studies on Ionic Liquids

Microreactor technology and continuous flow processing in general are key features in making organic synthesis both more economical and environmentally friendly. Heterogeneous catalytic hydrogenation reactions under continuous flow conditions offer significant benefits compared to batch processes which are related to the unique gas-liquid-solid triphasic reaction conditions present in these transformations. In this review article recent developments in continuous flow heterogeneous catalytic hydrogenation reactions using molecular hydrogen are summarized. Available flow hydrogenation techniques, reactors, commonly used catalysts and examples of synthetic applications with an emphasis on laboratory-scale flow hydrogenation reactions are presented.

Heterogeneous Catalytic Hydrogenation Reactions in Continuous‐Flow Reactors

Preface. Hydrogenation Catalysts. Reactors and Reaction Conditions. Hydrogenation of Alkenes. Hydrogenation of Alkynes. Hydrogenation of Aldehydes and Ketones. Preparation of Amines by Reductive Alkylation. Hydrogenation of Nitriles. Hydrogenation of Imines, Oximes, and Related Compounds. Hydrogenation of Nitro, Nitroso, and Related Compounds. Hydrogenation of Carboxylic Acids, Esters, and Related Compounds. Hydrogenation of Aromatic Compounds. Hydrogenation of Heterocyclic Aromatic Compounds. Hydrogenolysis. General Bibliography. Author Index. Subject Index.

Handbook of heterogeneous catalytic hydrogenation for organic synthesis

This review surveys the recent developments to perform heterogeneous catalysis in continuous-flow microreactors. Three different types, namely, (i) packed-bed, (ii) monolithic, and (iii) wall-coated approaches are discussed to implement various kinds of catalysts in a microreactor. In addition, the applications of these supported catalysts to perform a variety of organic reactions are described. Furthermore, advantages of catalytic microreactors over classical batch reactors on one or more aspects of the reaction, such as rate, conversion, selectivity, and enantioselectivity are presented

Supported Catalysis in Continuous-Flow Microreactors

Recent advances in micro reaction technology

Catalytic hydrogenation of o-nitroanisole in a microreactor : Reactor performance and kinetic studies

Comparison of performance of microreactor and semi-batch reactor for catalytic hydrogenation of o-nitroanisole

Catalytic hydrogenation of nitro aromatics is an important class of reactions in the pharmaceutical and fine chemical industries. These reactions are extremely fast and highly exothermic in nature; hence, mass and heat transfer limitations play an important role when these reactions are conducted in conventional batch reactors. The use of a micro-channel reactor for such reactions provides improved mass transfer rates which may ensure that the reaction operates close to intrinsic kinetics. In the present study, the hydrogenation of a model aromatic nitro ketone was conducted in a packed-bed microreactor. The effects of different processing conditions were studied using 5%Pd/Alumina catalyst, viz.: hydrogen pressure, substrate concentration, temperature, and residence time on the conversion of substrate, Space Time Yield (STY), and selectivity of product. Internal and external mass and heat transfer limitations in the microreactor were examined. The kinetic study was undertaken in a differential reactor mode, keeping the conversion of the reactant at less than 10%. The overall reaction was treated as comprising two separate reactions: first, the reduction of the nitro compound to hydroxylamine and then, the reduction of the hydroxylamine to amine. Two rate equations for the two consecutive reactions assuming the Langmuir-Hinshelwood mechanism provided the best fit to the experimental data. These two rate equations predicted the experimental rates satisfactorily and the differences were within 10% error. Experiments were also carried out in an integral reactor, and the reactor performance ∗This work is funded by the DOE-ITP under contract DE-FC36-02GO13156. The authors gratefully acknowledge the support. We also acknowledge the technical contributions of: Dr. Jale Muslehiddinoglu, Donald Kientzler and Dr. San Kiang of Bristol-Myers Squibb, our industrial partner; Prof. Suphan Kovenklioglu for his helpful suggestions; and all the members of NJCMCS, especially Dr. Dongying Qian and Dr. Raghunath Halder for their help throughout the research work. data were found to be in agreement with the predictions of the theoretical models.

/pdf/the-catalytic-hydrogenation-of-aromatic-nitro-ketone-in-a-51770yqvb4.pdf

The Catalytic Hydrogenation of Aromatic Nitro Ketone in a Microreactor: Reactor Performance and Kinetic Studies

The cycloaddition reaction between isoamylene and α-methylstyrene yields indane compounds 1,1,2,3,3,-pentamethylindane and 3-ethyl-1,1,3-trimethylindane, which are intermediate cyclic products used in the synthesis of musk fragrances. This exothermic reaction is usually carried out industrially in large semibatch reactors. The microreactor, with enhanced heat and mass transfer characteristics, was used for the reaction with aqueous sulfuric acid as catalyst. The dependence of reactant conversion, product yield, and average reaction rates on catalyst concentration, temperature, velocity, residence time, and the molar ratio of the reactants in the feed was investigated. A similar study was also performed in the semibatch reactor to compare its performance with that of the microreactor. Higher product yields were obtained in the microreactor, and the average reaction rates in the microreactor were 3 orders of magnitude greater than those obtained in the semibatch reactor.

Microreactor Performance Studies of the Cycloaddition of Isoamylene and α-Methylstyrene

The cycloaddition reaction between isoamylene and ?-methylstyrene yields indane compounds 1,1,2,3,3,-pentamethylindane and 3-ethyl-1,1,3-trimethylindane, which are intermediate cyclic products used in the synthesis of musk fragrances. This exothermic reaction is conventionally carried out industrially in large semi-batch reactors, which have high heat and mass transfer resistances, are difficult to optimize, and scale-up. Aqueous sulfuric acid is conventionally used as the catalyst for the cycloaddition reaction, but solid catalysts offer many advantages over the corrosive aqueous sulfuric acid catalyst including the elimination of expensive separation and purification steps, and the need to use corrosion resistant materials of construction. A microreactor, which has enhanced heat and mass transfer characteristics, high surface to volume ratio, and improved fluid mixing, was used for the reaction using an acidic solid catalyst, Filtrol-24. A parametric study to obtain the dependence of product yield, reactant conversion and space-time yield on process variables such as catalyst particle size, residence time, velocity, temperature, pressure and the molar ratio of the reactants in the feed, was conducted. Through this study the optimum reaction conditions were obtained. The cycloaddition reaction was also performed in the semi-batch reactor using Filtrol-24 catalyst in order to compare its performance to that of the microreactor. Higher product yields were obtained in the microreactor compared to the semi-batch reactor, and the space-time yield in the microreactor was 4.8 times larger than that obtained in the semi-batch reactor at optimum reaction conditions in both reactors.

Cycloaddition of Isoamylene and ?-Methylstyrene in a Microreactor using Filtrol-24 catalyst: Microreactor Performance Study and Comparison with Semi-Batch Reactor Performance

Sunitha Tadepalli

Papers

Catalytic hydrogenation of o-nitroanisole in a microreactor : Reactor performance and kinetic studies

Comparison of performance of microreactor and semi-batch reactor for catalytic hydrogenation of o-nitroanisole

The Catalytic Hydrogenation of Aromatic Nitro Ketone in a Microreactor: Reactor Performance and Kinetic Studies

Microreactor Performance Studies of the Cycloaddition of Isoamylene and α-Methylstyrene

Cycloaddition of Isoamylene and ?-Methylstyrene in a Microreactor using Filtrol-24 catalyst: Microreactor Performance Study and Comparison with Semi-Batch Reactor Performance