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• Pt@HA exhibited excellent catalytic selectivity in hydrogenation of quinoline via hydrogen spillover. • Spillover process discriminated the hydrogenation of pyridine and benzene moiety in quinoline molecule. • Hydroxyl groups on HA zeolite strengthened adsorption of pyridine moiety to facilitate its hydrogenation process. Hydrogen spillover has been widely used in heterogeneous catalysis, yet how to explore the potential of catalyst support to further promote catalytic function of hydrogen spillover has rarely been investigated. Herein, platinum encapsulated into amorphized HA zeolite (denoted as Pt@HA) with generated hydroxyl groups was used as model catalyst to study the role of HA zeolite support on the promotion of catalytic performance in hydrogenation of quinolines to tetrahydroquinolines. Benefiting from small pore size of amorphized HA zeolite to prevent direct interaction of quinoline with encapsulated platinum, Pt@HA showed good catalytic selectivity in this transformation through hydrogen spillover. This remarkable catalytic selectivity was resulted from the interaction of hydroxyl groups at surface of HA zeolite with pyridine moiety through the formation N H bond to facilitate adsorption to make much lower apparent activation energy of Pt@HA for hydrogenation of pyridine moiety than that of benzene moiety, thus exhibiting enhanced catalytic selectivity. [Display omitted] [ABSTRACT FROM AUTHOR]

Design of heterogeneous catalyst to achieve efficient conversion of biomass to high added-value chemicals is still very attractive. Herein, taking industrially important selective hydrogenation of furfural to furfuryl alcohol as an example, the designed amorphized HA zeolite encapsulation of platinum clusters (denoted as Pt@HA) exhibited excellent catalytic selectivity at totally conversion of the reactant furfural, along with good reusability and poison resistance ability. The selected amorphized HA zeolite with very small pore size constrained the reactant furfural to be reacted through hydrogen spillover process at zeolite surface, instead of to be adsorbed and activated onto Pt surface. Resulting from the stronger interaction between nucleophilic oxygen atom of aldehyde group and acid site at HA zeolite surface than that of furan ring group, furfural preferred to adsorb onto Pt@HA surface with the end of aldehyde group rather than the end of furan ring group, thus facilitating the spilled H atom to react with aldehyde group to give desired furfuryl alcohol product exclusively. [Display omitted] • Pt@HA exhibited remarkable catalytic property in hydrogenation of furfural to furfuryl alcohol via hydrogen spillover. • Spillover process disfavored activation of aldehyde group and furan ring simultaneously in one furfural molecule. • Acid sites on HA zeolite surface promoted adsorption of aldehyde group to facilitate its hydrogenation process. [ABSTRACT FROM AUTHOR]

Herein, we reported that the platinum (Pt) clusters encapsulated into sodalite (SOD) zeolite as catalyst exhibited 100 % selectivity at 100 % conversion in the selective hydrogenation of p‐chloronitrobenzene to p‐chloroaniline via hydrogen spillover. The direct interaction between p‐chloronitrobenzene and encapsulated Pt was prevented by the shape selectivity of SOD zeolite, reactants were thereby adsorbed onto zeolite outer surface to facilitate the hydrogenation proceeding by hydrogen spillover process. The further kinetic study and DFT calculation showed the excellent catalytic selectivity was ascribed to the much faster rate of hydrogenation of adsorbed nitro group than that of adsorbed C−Cl group. [ABSTRACT FROM AUTHOR]

It is challenging to establish single metal atoms with a uniform coordination environment at targeted sites of a zeolite. In this study, single platinum atoms were selectively encaged in the six‐membered rings of sodalite (SOD) cages within Y zeolite using a template‐guiding strategy. During the in situ synthesis process, template molecules were designed to occupy supercages and thereby force coordinated platinum species into SOD cages. Subsequent control of the post‐treatment conditions yielded the Y zeolite with selectively encaged single platinum atoms, denoted Pt@Y‐SOD. The Pt@Y‐SOD catalyst had good stability and excellent catalytic selectivity in the semihydrogenation reaction, and it exhibited interesting thiophene and carbon monoxide resistance in this transformation because interactions with these poisons are weakened by the configuration of the encaged single platinum atoms. [ABSTRACT FROM AUTHOR]

It is challenging to establish single metal atoms with a uniform coordination environment at targeted sites of a zeolite. In this study, single platinum atoms were selectively encaged in the six‐membered rings of sodalite (SOD) cages within Y zeolite using a template‐guiding strategy. During the in situ synthesis process, template molecules were designed to occupy supercages and thereby force coordinated platinum species into SOD cages. Subsequent control of the post‐treatment conditions yielded the Y zeolite with selectively encaged single platinum atoms, denoted Pt@Y‐SOD. The Pt@Y‐SOD catalyst had good stability and excellent catalytic selectivity in the semihydrogenation reaction, and it exhibited interesting thiophene and carbon monoxide resistance in this transformation because interactions with these poisons are weakened by the configuration of the encaged single platinum atoms. [ABSTRACT FROM AUTHOR]

Pyrolysis of digestate from anaerobic digestion of kitchen waste yielded combustible gas and liquid with biochar as solid product. In this study, the pyrolysis characterization of the digestate and the P availability of the obtained pyrochar were discussed. Thermogravimetry (TG) analysis showed that 15.56 % of the weight loss occurred from 600 °C to 750 °C due to CaCO 3 decomposition. When the final temperature increased from 500 °C to 700 °C, the HHV of pyrogas was slightly affected elevated from 17.20 MJ/Nm3 to 18.12 MJ/Nm3, while the relative content of polycyclic aromatic hydrocarbons (PAHs) in the liquid raised from 1.36 % to 6.28 %. SMT analysis showed that phosphorus in the pyrochar was fully converted to apatite phosphorus (AP) due to an excessive Ca content. Neutral ammonia citrate (NAC) extraction indicated that the availability of P in pyrochar was significantly decreased from 7.97 mg/g at 500 °C to 2.29 mg/g at 700 °C. Overall, the results showed that pyrolysis at 500 °C was suitable to obtain high-quality fuel and pyrochar with high P availability. [Display omitted] • The gas and liquid products from kitchen waste digestate pyrolysis are analyzed. • OP and NAIP in digestate is almost transformed into AP after pyrolysis. • The NACP content in pyrochar achieves its highest value when pyrolyzed at 500 °C. [ABSTRACT FROM AUTHOR]