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[Display omitted] • Rapid crystallization of Zr-Beta with high Zr content possible with MCLA protocol. • Zr-Beta formed with high crystallinity and hydrophobicity. • High Zr loadings useful in MPV reduction of sterically hindered ketones and diones. • MCLA-synthesized Zr-Beta is less susceptible to poisoning by water adsorption. Heteroatom-incorporated zeolite catalysts are critical for biomass utilization and feedstock valorization in green chemistry. Key features are adjustable acidity, high stability, and a tailored range of functionalities. However, an environmentally benign synthesis of zeolites with good crystallinity and especially with high levels of metal substitution into the lattice remains challenging. Here, we propose a mechanochemistry-based liquid-assisted method (MCLA) for Zr-incorporated Beta zeolites that is high yielding, facile and sustainable. Compared with the fluoride-mediated hydrothermal method, crystallization times were considerably shortened so that Si-Beta and Zr-Beta (Si/Zr 100) zeolites can be synthesized within 9 and 15 h, respectively. Using the MCLA route, Beta zeolites with Zr loading up to 10.4 wt% (Si/Zr 12.5) were obtained. The materials have excellent catalytic activity for Meerwein-Ponndorf-Verley reductions with much higher water tolerance compared to Zr-Beta prepared by the post-synthesis method. The hydrophobic nature of the MCLA-synthesized zeolites makes them particularly useful as catalysts for organic reactions. [ABSTRACT FROM AUTHOR]

• One-pot cascade transformation of furfural to γ-valerolactone in open system. • Zr-HY is an excellent MPV catalyst for reduction of furfural and levulinate ester. • Variable combination of Lewis and Brønsted acidic sites in mixture of Zr-HY and Al-HY zeolites. • High yields of γ-valerolactone within short reaction times. A highly efficient catalyst system was developed for the one-pot transformation of furfural to γ -valerolactone (GVL) in an open system. The cascade of two Meerwein Ponndorf Verley (MPV) reductions, ring-opening and esterification reactions was catalyzed by a physical mixture of Zr- and Al-HY zeolites where the proportion and strength of Lewis and Brønsted acid sites could be independently optimized. The excellent activity of Zr-HY zeolites for the MPV reduction of furfural and levulinate ester with 2-pentanol as hydrogen donor was attributed to the larger pore size of HY-zeolites and stronger Lewis acidic sites compared to Zr-Beta. Al-HY zeolites were more effective as Brønsted acid than Al-Beta because they converted furfuryl ether to levulinate ester rather than to β -angelica lactone. The dual catalytic system comprising Zr-HY (Si/Zr 20) and Al-HY (Si/Al 6) exhibited remarkably high catalytic activity with GVL yields of 85% after only 5 h at 120 °C. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of CO 2 into fuels could mitigate global warming and energy shortage simultaneously. In this study, the reaction pressure was optimized for CO 2 reduction by H 2 . The major products were methane, CO, and methanol, and the observed catalytic activity order was Cu or Pd on TiO 2 ≫ Ag/ZrO 2 ∼ g-C 3 N 4 > Ag/Zn 3 Ga-layered double hydroxide ∼ BiOCl. Hot/excited electrons due to surface plasmon resonance could be transferred to CO 2 -derived species and the remaining positive charge could combine with excited electrons in the semiconductor. As the levels of hot/excited electrons became more negative, the catalysts became more active, except for Ag/ZrO 2 and Ag/Zn 3 Ga-LDH, probably due to lower charge separation efficiency for intrinsic semiconductors or hydroxides. The reaction order was controlled by the partial pressure of H 2 , demonstrating preferable adsorption of H on Pd. The photoconversion of CO 2 into methane was optimum at P H2 = 0.28 MPa and P CO2 = 0.12 MPa, but the rates gradually dropped at higher partial pressures due to adsorption of CO 2 being hindered by H. [ABSTRACT FROM AUTHOR]