Snehasis Dutta , Bogdan Shumeiko , Jaroslav Aubrecht , Kateřina Karásková , Dagmar Fridrichová , Kateřina Pacultová , Tomáš Hlinčík , David Kubička
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引用次数: 0
Abstract
Anisole is a model molecule for studying hydrodeoxygenation (HDO) of lignin-derived oxygenates. Here we elucidate its HDO pathway over 10 % Ni/Al2O3 catalyst. Adsorption experiments showed that anisole is adsorbed on the acidic sites of the Al2O3. Anisole adsorption at 200–300 °C is reactive in nature, and results in its demethylation. The catalyst was tested at 100–300 °C, 5–40 bar H2 pressure. Conversion of 78 % was obtained at 5 bar and 300 °C, restricted by hydrogenation-dehydrogenation equilibrium. HDO mainly starts through the ring-hydrogenation pathway. This is followed by demethoxylation beyond 180 °C. At 5–12 bar, cyclohexane dehydrogenates to benzene. This was confirmed by conducting an HDO experiment with methoxycyclohexane. At lower pressure deoxygenation is favored; and demethylation is accompanied with methylation of the aromatic ring, for temperature >260 °C. Investigation of the initial reaction stages showed that anisole HDO on Ni/Al2O3 catalyst proceeds via two independent pathways i.e., reactive adsorption/(de)methylation and aromatic ring hydrogenation.
期刊介绍:
The Journal of Catalysis publishes scholarly articles on both heterogeneous and homogeneous catalysis, covering a wide range of chemical transformations. These include various types of catalysis, such as those mediated by photons, plasmons, and electrons. The focus of the studies is to understand the relationship between catalytic function and the underlying chemical properties of surfaces and metal complexes.
The articles in the journal offer innovative concepts and explore the synthesis and kinetics of inorganic solids and homogeneous complexes. Furthermore, they discuss spectroscopic techniques for characterizing catalysts, investigate the interaction of probes and reacting species with catalysts, and employ theoretical methods.
The research presented in the journal should have direct relevance to the field of catalytic processes, addressing either fundamental aspects or applications of catalysis.