Controlled synthesis of porous metal oxides with desired morphology has been motivating scientists to explore and develop new preparation methodologies. Among them, thermal decomposition of metal–organic frameworks (MOFs) has been employed for the fabrication of several metal oxides. In this work, this strategy is employed to prepare mesoporous and tetragonal zirconia (t-ZrO₂) from a metal–organic framework (UiO-66), acting as both a morphological template and a zirconium source. This process avoids the use and removal of an extra template as well as the addition of stabilizers for t-ZrO₂. After thermal decomposition at 500 °C, t-ZrO₂ inherited an octahedral morphology from the pristine precursor and possessed small nanoparticles with an average size of 3.1 nm. The derived t-ZrO₂ had a large surface area of 174 m² g⁻¹ and a pore diameter of 5–8 nm. The formation mechanism of t-ZrO₂ was also discussed. This simple and potentially universal strategy can be used to fabricate porous metal oxides with desired shape for many applications.

CO is a toxic gas discharged as a byproduct in tail gases from different industrial flue gases, which needs to be taken care of urgently. In this study, a CuCl/AC adsorbent was made by a facile route of physically mixing CuCl₂ and Cu(HCOO)₂ powder with activated carbon (AC), followed by heating at 533 K under vacuum. The samples were characterized by X-ray powder diffraction (XRD), inductively coupled plasma optical emission spectrometry (ICP-OES), N₂ adsorption/desorption, and scanning electron microscopy (SEM). It was shown that Cu(II) can be completely reduced to Cu(I), and the monolayer dispersion threshold of CuCl on AC support is 4 mmol·g⁻¹ AC. The adsorption isotherms of CO, CO₂, CH₄, and N₂ on CuCl/AC adsorbents were measured by the volumetric method, and the CO/CO₂, CO/CH₄, and CO/N₂ selectivities of the adsorbents were predicted using ideal adsorbed solution theory (IAST). The obtained adsorbent displayed a high CO adsorption capacity, high CO/N₂, CO/CH₄, and CO/CO₂ selectivities, excellent ad/desorption cycle performance, rapid adsorption rate, and appropriate isosteric heat of adsorption, which made it a promising adsorbent for CO separation and purification.

A mesoporous beta zeolite was hydrothermally prepared directly by silanizing silica without any mesoporous template via the bond-blocking principle. Si–C bond-blocking arose during the crystalline growth. The crystallization took more than 10 days, but the material had a fairly stable structure and could even be processed up to 32 days later in the hydrothermal system. XRD, N₂-adsorption/desorption and TEM/SEM characterization of the materials indicated that the beta zeolite is truly a sponge-like mesoporous zeolite with a BEA topological structure, which consists of self-sustaining macroscopic sized zeolitic aggregates assembled from nanosized crystalline domains of beta zeolite with intracrystalline mesopores. The mesoporous beta zeolite possessed an extremely large external surface area and adjustable mesoporosity. Compared to conventional beta zeolite, FTIR results of pyridine (Py) and 2,6-di-tert-butylpyridine (DTBPy) demonstrated an increase of the Lewis-site contribution and a large improvement for the accessibility of bulky molecules in the mesoporous beta zeolite. Finally the mesoporous beta zeolite exhibited significant activity in the transesterification reaction of triolein to afford methyl oleate (biodiesel) due to the accessibility increase and diffusion-limitation reduction of large lipids to acid sites in the H-beta zeolite framework.