Debye Institute for Nanomaterials Science

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Inorganic Chemistry and Catalysis
Development of a hydrothermal stable non-noble metal catalyst for
Aqueous Phase Reforming
Tomas van Haasterecht, T.vanHaasterecht@uu.nl, phone: 06 - 22736372
Sponsor: Catchbio, since January 2009
Supervisors: Prof. dr. ir. Krijn P. de Jong and dr. Johannes H. Bitter
H 2 -Chemisorption, HPLC/RID, GC/TCD, AAS
Aqueous phase reforming (APR) of renewable carbohydrates is an attractive process for the
sustainable and economical production of H . The generated H can be used for efficient power
2 2
generation in a PEM fuel cell. Using APR with microreactor technology and an integrated fuel
cell, we aim for the development of a compact power producing unit for portable applications, this
part of the project is in collaboration with the TUE.
In the APR process biomass derived oxygenated hydrocarbons are converted into, preferably H2 and CO , around 500 K using heterogeneous metal catalysts.
2
So far the process has been most successful using expensive platinum based catalyst and glycols as
feedstock. [1] This research focuses on the development of a stable, non noble metal catalyst for the
efficient and selective production of H from various biomass feeds. The most promising catalyst
2
can be integrated in the microreactor system at the TUE to demonstrate the applicability.
We have investigate the possibility of using Carbon Nanofiber (CNF) supported Co, Ni and Cu
catalysts with a focus on their hydrothermal stability. These catalysts, and a commercial 5%Pt/Al O 2 3
catalyst, were tested in a batch reactor for the APR of a 1% Ethylene Glycol (EG) solution. The
resulting conversion profiles are shown in Fig. 1. The highest conversion was achieved with the
Ni/CNF catalyst while the Cu/CNF is almost inactive. The initial activity in terms of TOFi,EG
is highest for the Co/CNF catalyst, however after an initial period of high activity the Co/CNF
catalyst appears to deactivate.
Indeed XRD analysis of the spent catalysts shows that Co/CNF is subject to sintering and oxidation.
The Ni, Cu and Pt catalysts remain metallic, but sintering also occurs for the Ni/CNF catalyst.
Furthermore, the amount of leached metal, detected in the liquid phase after the reaction, was
significantly higher for the Co/CNF catalyst compared to other catalysts. Based on these result the
Ni/CNF is the most promising alternative to platinum based catalyst in terms of activity and stability.
Figure 1: EG conversion as function of time.
[1] Appl. Catal. B. 56, 2005, 171.