Influence of reduction temperature on the formation of intermetallic Pd₂Ga phase and its catalytic activity in CO₂ hydrogenation to methanol

Abstract

The global warming and change in climatic conditions due to rising concentration of CO2 in atmosphere are the most important challenges of 21st century. Catalytic conversion of CO2 to methanol will not only check global warming but also provide an alternative source of fuel. The phase purity of solid catalysts has a considerable influence on the desired product selectivity. Reduction temperature is one of the most important parameters responsible for catalyst phase formation. Herein, the effect of a range of reduction temperatures between 100 and 600°C on the phase composition of Pd–Ga bimetallic catalyst and CO2 hydrogenation to methanol activity was investigated. X‐ray diffraction (XRD) analysis revealed the formation of different phases at different reduction temperatures. The variation in catalyst structure was also analyzed using field emission scanning electron microscope‐energy dispersive X‐ray spectroscopy (FESEM‐EDS), Brunaue–Emmett–Teller, H2 chemisorption, and transmission electron microscopy techniques. The influence of reduction temperature, pressure (1–25 bar), H2/CO2 ratio (3–9), and reaction temperature (150–250°C) on methanol and CO selectivity from CO2 hydrogenation at atmospheric pressure was also studied. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.

Anchoring ultrasmall Pd nanoparticles by bipyridine functional covalent organic frameworks for semihydrogenation of acetylene

“…On the other hand, the reduction by H 2 has to be conducted under high temperature (120 °C), which can be inclined to result in aggregation of Pd particles. 42,43…”

“…On the other hand, the reduction by H 2 has to be conducted under high temperature (120 °C), which can be inclined to result in aggregation of Pd particles. 42,43 Moreover, the effect of Pd loading on the catalytic activity of Pd@TbBpy was explored. As shown in Fig.…”

Sensing and conversion of carbon dioxide to methanol using Ag-decorated zinc oxide nanocatalyst

“…21 Therefore, converting CO 2 into some useful by-products via the reaction of CO 2 + 3H 2 → CH 3 OH + H 2 O to reduce its harmful environmental impact is crucial. 22,23 In light of the aforementioned threats posed by CO 2 gas, methods must be developed for sensing, monitoring, and controlling the emission of contaminants polluting the Earth's atmosphere. In the last 20 years, researchers have attempted to develop heterogeneous catalysts for CO 2 hydrogenation to methanol as a byproduct.…”

Chemical Bonding in the Catalytic Platform Material Ga1‐xSnxPd2

“…The intermetallic compound GaPd 2 , which started out as a component in dental amalgams, [1] has been developed into a platform material [2] for quite a number of catalytic reactions. These include the selective hydrogenation of acetylene, which is an important industrial process to clean the ethylene feed for the production of polyethylene (80×10 6 t/a [3] ) or ethylene oxide (10×10 6 t/a [4] ) in the gas phase[ 5 , 6 , 7 , 8 ] (also propyne [9] ) and in the liquid phase, [10] furthermore in methanol steam reforming to release high‐purity hydrogen from methanol/water mixtures,[ 12 , 13 , 14 , 15 ] and finally in the synthesis of methanol from CO [16] or CO 2 ,[ 16 , 17 , 18 , 19 , 20 , 21 , 22 ] as well as for the synthesis of dimethyl ether (DME) from CO and the electrocatalytic hydrogen evolution reaction [23] or methanol oxidation reaction. [24] The latter reactions, in particular, enable an efficient synthesis, or use of, methanol/DME as chemical storage molecules for a hydrogen‐based energy infrastructure ( methanol economy [25] ).…”