Laitinen, T.; Ojala, S.; Genty, E.; Brunet, J.; De Weireld, G.; Poupin, C.; Siffert, S.; Cousin, R.; Keiski, R.L. On the Activity and Selectivity of CoAl and CoAlCe Mixed Oxides in Formaldehyde Production from Pulp Mill Emissions. Catalysts 2020, 10, 424. https://doi.org/10.3390/catal10040424
On the activity and selectivity of CoAl and CoAlCe mixed oxides in formaldehyde production from pulp mill emissions
|Author:||Laitinen, Tiina1; Ojala, Satu1; Genty, Eric2;|
1Environmental and Chemical Engineering (ECE), Faculty of Technology, University of Oulu, P.O. Box 4300, University of Oulu, FI-90014 Oulu, Finland
2Unité de Chimie Environnemental et Interactions sur le Vivant (UCEIV), Université du Littoral Côte d’Opale, 59140 Dunkerque, France
3Faculté Polytechnique de Mons, Université de Mons, 20 Place du Parc, B-7000 Mons, Belgium
|Online Access:||PDF Full Text (PDF, 6.2 MB)|
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe2020070747075
Multidisciplinary Digital Publishing Institute,
|Publish Date:|| 2020-07-07
Contaminated methanol has very good potential for being utilized in formaldehyde production instead of its destructive abatement. The activities, selectivities and stabilities of cobalt–alumina and cobalt–alumina–ceria catalysts prepared by the hydrotalcite-method were investigated in formaldehyde production from emissions of methanol and methanethiol. Catalysts were thoroughly characterized and the relationships between the characterization results and the catalytic performances were drawn. The preparation method used led to the formation of spinel-type structures in the form of Co₂AlO₄ based on x-ray diffraction (XRD) and Raman spectroscopy. Ceria seems to be present as CeO₂, even though interaction with alumina is possible in the fresh catalyst. The same structure is maintained after pelletizing the cobalt–alumina–ceria catalyst. The cobalt–alumina–ceria catalyst was slightly better in formaldehyde production, probably due to lower redox temperatures and higher amounts of acidity and basicity. Methanol conversion is negatively affected by the presence of methanethiol; however, formaldehyde yields are improved. The stability of the pelletized catalyst was promising based on a 16 h experiment. During the experiment, cobalt was oxidized (Co2+ → Co3+), cerium was reduced (Ce4+ → Ce3+) and sulfates were formed, especially on the outer surface of the pellet. These changes affected the low temperature performance of the catalyst; however, the formaldehyde yield was unchanged.
|Type of Publication:||
A1 Journal article – refereed
|Field of Science:||
218 Environmental engineering
This research was funded by the Academy of Finland (ELECTRA-project, 319448 number), the Jenny and Antti Wihuri foundation, the Finnish Cultural Foundation—North Ostrobotnia regional fund and the Riitta and Jorma J. Takanen foundation.
|Academy of Finland Grant Number:||
319448 (Academy of Finland Funding decision)
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).