Recent Advances in Hydrogenation Reactions Using Bimetallic Nanocatalysts: A Review

Abstract

Hydrogenation reactions have been studied for many decades now and have developed from reactions that appear simple to now being recognized for their many complexities. These reactions are generally catalyzed using monometallic and more recently, with bimetallic nanocatalysts. Hydrogenation plays a vital role in food, chemical, petrochemical, pharmaceuticals, and dye industries to name a few. The hydrogenated products derived from several biomass-based compounds are potential fossil fuels. Such products when employed in daily life, can help conserve natural resources. While hydrogenation of alkynes and alkenes are among the simplest of hydrogenation reactions, the most extensive and elegant manifestation of this reaction is seen in polymerization. Polymers like polythene, polypropylene (plastic) have replaced materials like glass, stainless steel, etc., in making daily use items for the obvious advantages of the former. Purification of alkenes is achieved by partially hydrogenating the respective alkynes present in trace amounts. This serves as an important step in the polymerization process. The presence of nitro group on aromatic rings makes them carcinogenic in nature which harms living organisms. For a safe environment, the elimination or modification of this nitro group becomes imperative. The products of hydrogenation of nitroaromatics and amino aromatics form the basis of pharmaceuticals and dyestuffs. A plethora of bimetallic catalysts have been used to catalyze these hydrogenation reactions. These catalysts are evaluated based on their selectivity and efficiency. This review highlights the recent advancements in the field of hydrogenation of nitro compounds, carbonyl compounds, and unsaturated hydrocarbons catalyzed by bimetallic nanoparticles.

Catalytic Continuous Reductive Amination with Hydrogen in Flow Reactors

“…[2][3][4][5] Moreover, due to the ubiquity of amino groups in drugs and biomolecules, amine compounds are indispensable for the pharmaceutical industry. [6,7] Many methods have been developed to obtain amines, such as reductive amination, [8,9] hydrogenation of nitrile, [10][11][12] hydrogenation of nitro groups, [13,14] amination of alkyl halides, [15,16] etc. Among these methods, reductive amination is a convenient way to construct various amines from accessible aldehydes and ketones.…”

Highly Active Bimetallic Single-Atom Alloy PdAg Catalysts on Cerium-Containing Supports in the Hydrogenation of Alkynes to Alkenes

“…Its using as a support Abbreviations and notation: DPA, diphenylacetylene; HRTEM, high resolution transmission electron microscopy; EDX, energy dispersive X-ray spectroscopy; TOF, catalyst turnover frequency; r, the rate of reaction. makes it possible to increase the dispersion of a supported metal and to vary the electron density on metal nanoparticles [5,13,17]. In some cases, sites on the periphery of nanoparticles at the metal-support interface, which include both the nanoparticle metal atoms and the surface atoms of the support, can play an important role.…”