Author: Samuel M. FehrPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Surface Analysis of Cu/ZnO Catalysts for Methanol Synthesis - a Study on Nitrous Oxide Chemisorption and DRIFT Spectroscopy
Author: Samuel M. FehrSurface Analysis of Cu/ZnO Catalysts for Methanol Synthesis - a Study on Nitrous Oxide Chemisorption and DRIFT Spectroscopy
Author: Samuel M. FehrAdsorption and Deactivation Characteristics of Cu/ZnO-Based Catalysts for Methanol Synthesis from Carbon Dioxide
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 12
Book Description
The adsorption and deactivation characteristics of coprecipitated Cu/ZnO-based catalysts were examined and correlated to their performance in methanol synthesis from CO2 hydrogenation. The addition of Ga2O3 and Y2O3 promoters is shown to increase the Cu surface area and CO2/H2 adsorption capacities of the catalysts and enhance methanol synthesis activity. Infrared studies showed that CO2 adsorbs spontaneously on these catalysts at room temperature as both monoand bi-dentate carbonate species. These weakly bound species desorb completely from the catalyst surface by 200 °C while other carbonate species persist up to 500 °C. Characterization using N2O decomposition, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) with energy-dispersive X-ray spectroscopy (EDX) analysis clearly indicated that Cu sintering is the main cause of catalyst deactivation. Ga and Y promotion improves the catalyst stability by suppressing the agglomeration of Cu and ZnO particles under pretreatment and reaction conditions.
Identification and Characterization of Active Sites and Stable Surface Intermediates on Copper-based Methanol Synthesis Catalysts by Temperature-programmed Desorption and FTIR Spectroscopy
Author: David Lloyd RobertsFTIR Studies of Dynamic Surface Structural Changes in Cu/ZnO Methanol Synthesis Catalysts
Author: Nan-Yu TopsøePublisher:
ISBN:
Category : Chemical engineering
Languages : en
Pages : 7
Book Description
Preparation and Characterization of Cu/Zno Catalysts
Author: Stefan ZanderPublisher: Sudwestdeutscher Verlag Fur Hochschulschriften AG
ISBN: 9783838150208
Category :
Languages : en
Pages : 132
Book Description
Methanol is one of the most important industrial base chemicals and also a starting material for many organic syntheses. A steadily rising amount is used as fuel or fuel additive because methanol can serve as liquid hydrogen carrier. In the chemical industry, methanol is produced from synthesis gas over Cu/ZnO based catalysts. The catalyst is prepared by a multi-step synthesis (co-precipitation, calcination, reduction). Already in early stages of the preparation structural characteristics can provide indications for the resulting activity of the final catalyst. In order to investigate correlations between preparation parameters, microstructure and activity of Cu/ZnO based catalysts, the effects of the pH during co-precipitation and aging, use of MgO instead of ZnO and doping with Ga-ions were examined in the present work. Precursors, calcined and reduced samples were investigated with different methods (XRD, XRF, physisorption, TPR, RFC, UV-Vis spectroscopy, XAS, XPS, SEM, TEM) and selected samples were tested in methanol synthesis.
Photoelectron Spectroscopic Studies of Model Catalyst Surfaces
Author: Stephen Vincent DidziulisPublisher:
ISBN:
Category :
Languages : en
Pages : 696
Book Description
Author: P. Vesborg
Author: Stefan Zander
Author: Lap-Hung Sunny Chan