Foam/fiber-structured catalysts: non-dip-coating fabrication strategy and applications in heterogeneous catalysis

Rh/CeO2 Thin Catalytic Layer Deposition on Alumina Foams: Catalytic Performance and Controlling Regimes in Biogas Reforming Processes

“…In all cases, the adherence of the catalytic layer to the alumina support was very good, with weight losses lower than 5%, in agreement with the literature [7,[30][31][32]44]. Therefore, SCS allowed overcoming the exfoliation of coatings usually encountered in conventional dip-coating techniques [7,39,62]. The good resistance of the coated layer to mechanical stress can be ascribed to the irregular porous surface of the support, which is beneficial to anchoring or interlocking the catalytic precursors (see Figure S1 in Supplementary Materials) [63].…”

“…On the other hand, the tortuous structure of ceramic open-cell foam (OCF) provides a fast radial heat and mass transport with higher contact efficiency [37,38]. Indeed, OCFs are macroporous reticulated three-dimensional (3D) structures in which the cells are connected by open windows, providing high porosity with 80-90% void space [39]. As an alternative to conventional systems (pellets made of magnesium aluminate or calcium aluminate spinels), alumina OCFs are potential structured supports for reforming processes with proven mechanical, chemical and hydrothermal suitability for severe working conditions: high temperature (600-900 • C), high pressure (20-30 bar) and steam rich environment (S/CH 4 = 1.5-3.0) [40,41].…”

Oxidative Dehydrogenation of Ethane: Superior Nb2O5-NiO/Ni-Foam Catalyst Tailored by Tuning Morphology of NiO-Precursors Grown on a Ni-Foam

“…Most notably, this catalyst exhibits favorable stability, being stable for at least 240 h at 400°C with ∼44% ethane conversion and ∼82% ethylene selectivity (Figure 5G), which shows great superiority when compared with the previously reported Nb 2 O 5 -NiO catalysts (Table S4). This is benefited from the high Nb 2 O 5 -NiO sintering resistance (evidenced by the well-preserved SSA and particle size of NiO for the used catalyst, Table 1), as a result of the strong interaction between NiO and Nb 2 O 5 (Solsona et al., 2011, Solsona et al., 2012) in combination with the enhanced heat transfer of the Ni-foam-structured designing that could rapidly dissipate the large quantity of reaction heat from the ODE reaction (Table S5) (Li et al., 2015, Zhao et al., 2016, Zhang et al., 2018a, Zhang et al., 2018b).…”

“…In addition, it is not surprising that the S4). This is benefited from the high Nb 2 O 5 -NiO sintering resistance (evidenced by the well-preserved SSA and particle size of NiO for the used catalyst, Table 1), as a result of the strong interaction between NiO and Nb 2 O 5 (Solsona et al, 2011 in combination with the enhanced heat transfer of the Ni-foam-structured designing that could rapidly dissipate the large quantity of reaction heat from the ODE reaction (Table S5) Zhao et al, 2016;Zhang et al, 2018aZhang et al, , 2018b.…”

“…Despite the above-mentioned interesting advances, the real-world use of these catalysts still remains a challenge as their poor thermal conductivity is detrimental to rapid dissipation of reaction heat released in this strongly exothermic ODE reaction (ΔH = −104 kJ mol −1 ), which causes severe hotspots in the catalyst bed and therefore leads to the ethylene excessive oxidation while releasing more heat. Recently, the development of structured catalyst based on the monolithic metal-foam has been attracting great interest in heterogeneous catalysis because of the intensified heat transfer, which is favorable to tailor catalysts for strongly exothermic reactions (Chen et al., 2019, Zhao et al., 2016, Zhang et al., 2018a, Zhang et al., 2018b). However, the main issue is how to make these promising metal-foam qualified catalysts, or more concretely, how to fabricate the highly active and selective NiO-based nanocomposites onto foam surface.…”