fulltext.study @t Gmail

Memory effect of the CuZnAl-LDH derived catalyst precursor—In situ XRD studies

Paper ID Volume ID Publish Year Pages File Format Full-Text
40138 45844 2013 9 PDF Available
Title
Memory effect of the CuZnAl-LDH derived catalyst precursor—In situ XRD studies
Abstract

•Characteristics of the CuZnAl-LDH precursor and ex-LDH materials as active copper catalysts.•In situ XRD studies of the initial layered structure recovery–memory effect.•Structural and textural changes of CuZnAl-LDH calcined up to 400 °C reversible to a large extent.•Above 600 °C the formation of irreversible highly crystalline non-layered oxides.•Correlation between the heat effect and degree of structure recovery.

Thermal decomposition of the CuZnAl-LDH catalyst precursor and the reverse structural transformations of the oxide forms upon addition of water have been investigated. The object of the studies was chosen in such a way that its composition resembled that of the industrial methanol synthesis and low-temperature water gas shift catalysts precursors. The temperature ranges of the corresponding transformations have been assigned and the structural changes have been discussed. The CuZnAl-LDH catalyst precursor shows a distinct “memory effect” up to the temperatures of 400–600 °C. The heat effect of the exothermic hydration process of the mixed oxides, (Cu,Zn)AlOx has been estimated and correlated with a degree of recovery of the material layered structure. Above 600 °C irreversible structural transformations proceed, leading in consequence to the gradual decline of this effect. The recovery kinetics of the layered ordered structure has been determined based on the in situ XRD measurements and Avrami–Erofeev's model.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (223 K)Download as PowerPoint slide

Keywords
CuZnAl catalyst precursor; Layered double hydroxides; Memory effect; Mixed metal oxides; XRD studies
First Page Preview
Memory effect of the CuZnAl-LDH derived catalyst precursor—In situ XRD studies
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Applied Catalysis A: General - Volumes 464–465, 15 August 2013, Pages 339–347
Authors
, , , , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Catalysis
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us