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Alkaline treatment (desilication) is an effective treatment to increase mesoporosity. However, the concomitant decrease in Si/Al ratio affects the strengths of the acidic sites and hence catalytic activity and selectivity. Therefore instead we subjected template containing zeolites to 1 M NaOH to induce additional porosity. All zeolites tested (ZSM-5, ZSM-12 and Beta) consisted of small crystallites (30–200 nm) that were agglomerated into larger particles between 1 and 5 μm. Mesopore formation occurred by slowly removing outer layers of individual crystallites, thereby preserving the Si/Al ratio as well as the crystallinity. Inter-crystalline mesopores were formed for all zeolites, but the treatment was most effective for zeolites with small crystallites. The external surface area of ZSM-5 was increased from 90 to 149 m2 g−1 and for zeolite Beta from 70 to 158 m2 g−1. The catalytic performance was tested at 413 K for 3 h for etherification of 1,2-propylene glycol with 1-octene to form octyl-ether. For ZSM-5, conversion increased from 1.2% to 5.6% upon alkaline treatment in the presence of a template, while only to 5% for the template-free treated sample with a significantly higher external surface area (205 m2 g−1). The parent zeolite Beta was significantly more active (30% conversion, 88% selectivity), which can be ascribed to its larger pore size. Nevertheless also in this case alkaline treatment in the presence of the template significantly increased the activity to 40% conversion with similar selectivity. As only the mesoporosity was changed upon alkaline treatment it suggests that the etherification of 1,2-propylene glycol with 1-octene is affected by intra-crystalline diffusion. Our work illustrates the possibilities to use alkaline treatment of templated zeolites to decouple accessibility changes from acidity, and to gain further insight in zeolite catalysis.

Control over the size and size distribution of supported nanoparticles is key to their efficient use in catalysis. In the preparation of nanoparticles by impregnation using nitrate precursors, the support pore diameter can be used to influence the average crystallite size. However, the particle size distributions obtained via this method are generally broad and the dispersions relatively low. Higher dispersions and narrow particle size distributions are obtained via thermal decomposition of the metal nitrate precursor in 1% (v/v) NO in Ar instead of air. Here we will show that by combining the confinement effect of ordered mesoporous silica with a decomposition step of metal nitrates in NO, silica supported nickel and cobalt oxides with a tunable particle size (2–4 nm) can be obtained at high loadings (10–20 wt%).