Samudrala Shanthi Priya

Catalytic performance of Pt/AlPO4 catalysts for selective hydrogenolysis of glycerol to 1,3-propanediol in the vapour phase

Hydrogenolysis of glycerol to 1,3-propanediol was investigated in the vapour phase over a series of Pt/AlPO4 catalysts with platinum loadings ranging from 0.5 to 3 wt%. The catalysts were prepared by a wet impregnation method and characterized by various techniques such as X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), BET surface area, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and CO-chemisorption methods. Ex situ pyridine adsorbed FTIR analysis and temperature programmed desorption (TPD) of NH3 were employed to investigate the acidic properties of the catalysts. Further, the effect of reaction temperature, hydrogen flow rate, glycerol concentration and various contents of platinum (0.5 to 3 wt%) have been investigated to find the optimum reaction conditions. Superior performance with almost 100% conversion of glycerol and above 35% selectivity to 1,3-propanediol was obtained over 2 wt% Pt/AlPO4 at 260 °C and atmospheric pressure. The influence of acidity of the catalyst and its correlation to the catalytic performance (selectivity and conversion) has been studied. The high strength of weak acidic sites and Bronsted acidity of the catalyst measured by NH3-TPD and Pyr-FTIR were concluded to play a key role in selective formation of 1,3-propanediol. XRD, TEM and CO-chemisorption studies revealed that platinum was well dispersed on AlPO4 which further contributed to higher catalytic activity for glycerol hydrogenolysis.

Direct Hydrogenolysis of Glycerol to Biopropanols over Metal Phosphate Supported Platinum Catalysts

Several metal phosphate supported platinum catalysts (Pt/AlP, Pt/TiP, Pt/ZrP and Pt/NbP) have been synthesized for the direct hydrogenolysis of glycerol to produce bio-propanols performed under mild reaction conditions. The catalysts were screened for its activity towards production of propanols from glycerol hydrogenolysis and the reaction has been optimized by studying various reaction parameters such as effect of platinum loading, reaction temperature, hydrogen flow rate, glycerol concentration and reaction time. Among the catalysts investigated, 2Pt/TiP presented a remarkable catalytic performance for vapour phase hydrogenolysis of glycerol with 100% conversion of glycerol and 97% selectivity to total propanols (1-propanol + 2-propanol) at 220 °C and atmospheric pressure. The high efficiency of 2Pt/TiP catalyst is probably be due to the strong acidity of catalyst and the uniform dispersion of small Pt particles on surface of TiP that could enable the dehydration-hydrogenation route of glycerol hydrogenolysis. Further, the structural characteristics of used catalyst have been investigated in order to understand the stability of the catalyst. Therefore, a more economical and sustainable approach of producing value added propanols from bio-derived glycerol over highly efficient catalytic system is herein presented.Graphical Abstract

Combining additive manufacturing and catalysis: a review

This review presents an insight into additive manufacturing (AM) technologies as they are applied to heterogeneous catalysis; the combination of these fields presents opportunities but also comes with challenges. AM enables greater design complexity, rapid prototyping, control over reactant stoichiometry and unique catalyst immobilisation options. The challenges to applying AM in heterogeneous catalysis are associated with limited material choices, quasi-stable printed materials and chemical interfacing of the catalyst system with cthese printed materials. AM printing technologies are introduced to the heterogeneous catalysis research community with a focus on the many benefits they offer in this growing field.

Synthesis of fluorenones by using Pd(II)/Mg–La mixed oxide catalyst

Palladium(II)/magnesium–lanthanum mixed oxide (Pd(II)/Mg–La mixed oxide) catalyst was used in the dehydrogenative cyclization of benzophenones to afford fluorenones. This protocol represents a direct and facile approach to accessing a variety of fluorenone derivatives by means of C–H activation under heterogeneous conditions. The catalyst was recovered by centrifugation and used for three consecutive cycles with nearly consistent activity and selectivity.