A Sustainable Palladium‐Intercalated Montmorillonite Clay Catalytic System for Imine Hydrogenation under Mild Conditions

Abstract

A series of palladium nanoparticles (Pd NPs) intercalated montmorillonite clay catalysts is reported for hydrogenation of 3-diphenyl prop-2-en-1-imine under mild reaction conditions. Pd/clay catalyst was prepared by a simple wet-impregnation method, and the physicochemical properties were characterized extensively by various techniques including N 2 adsorption, XRD, TEM, XPS and TPR etc., which showed the intercalation of active Pd NPs between the clay layers. The effect of reaction conditions such as catalyst loading, reaction time, temperature and H 2 pressure is explored, and thereby a plausible mechanism is proposed. The optimum amount of 6 wt % Pd/clay catalyst showed significant catalytic activity to yield 3-phenyl propyl aniline with 100 % conversion and selectivity under 5 bar pressure and a shorter reaction period of 3.5 h at 100°C. The developed catalytic system unveiled excellent reusability over five cycles and hence paved the way for industrial applications.

Metal–Acid Interface Engineering in Pd–WOx Bifunctional Catalysts for the Hydroalkylation Tandem Reaction of Benzene

“…Montmorillonite (MMT) is an ideal host for synthesizing bifunctional catalysts because of its unique attributes such as nanometer-scale platelets, mechanical and chemical stabilities, a large surface area, and commercially available at low price. − Herein, we report supported Pd–WO x catalysts on the MMT support with various WO x loadings (denoted as Pd– m WO x /MMT, m = 5, 15, and 25 wt %) based on a two-step procedure (Figure a). First, a thin coating of WO x was deposited on the MMT surface (denoted as WO x /MMT) via calcination of W-precursor-containing MMT; then, the palladium species was immobilized onto the surface of WO x /MMT by an impregnation–reduction approach.…”

Modification of Pillared Intercalated Montmorillonite Clay as Heterogeneous Pd Catalyst Supports

“…For example, pillared intercalated montmorillonite clays (PM) can be prepared by intercalation of inorganic or organic compounds between the clay layers, resulting in an increased basal spacing, enlarged interlayer spaces, larger pore volume, and higher surface specific area. Due to such textural structure characteristics, PM-based materials are highly attractive for adsorption and catalytic applications [10][11][12]. For example, active Pd nanoparticles are readily introduced into the interlayer spaces of PM to prepare novel advanced catalytic composites for combustion of volatile organic compounds, combustion of propene, and C-C coupling reactions [13][14][15][16].…”