Jia Wang,Jianchun Jiang,Xianzhi Meng,Su Shiung Lam,Arthur J. Ragauskas,Yanqin Wang
Chemical upcycling rubber wastes into hydrocarbon fuels offers a promising approach toward achieving carbon neutrality . To generate fuel-range cycloalkanes and isoalkanes from natural rubber glove wastes (NRGWs), the depolymerization of NRGWs was performed by integrating hydropyrolysis with vapor-phase hydrogenation over a bifunctional Ni/Al 2 O 3 -SiO 2 catalyst. Isoprene and limonene were the primary alkenes obtained from the non-catalytic hydropyrolysis of NRGWs, and these intermediates were vapor-phase hydrotreated over Ni/Al 2 O 3 -SiO 2 producing C 10 cycloalkane as the dominant fuel-range products. Complete hydrogenation of isoprene and limonene was achieved under a catalyst to feedstock mass ratio of 2.0, giving a maximum gasoline yield of 92 wt% under 225 °C hydrogenation temperature at 0.2 MPa H 2 . A low hydropyrolysis temperature of 450 °C maximized C 10 cycloalkane yield at 72.3 wt% with 80.1% selectivity, while a high temperature of 600 °C yielded 76.6 wt% C 5 isoalkane. A deconstruction mechanism in the catalytic cascade upcycling of NRGWs was proposed by employing limonene hydrogenation as a probe reaction. The results demonstrate that upcycling polymer wastes by cascade hydropyrolysis‑hydrogenation is a promising approach to produce alternative fuels with improved properties.
Catalysts with an open hollow structure can enhance the mass transfer capability of the catalyst during the reaction process, thereby further improving the catalytic performance. In this work, uniform and monodisperse flying-squircher-shaped Al-MOFs were synthesized via a solvothermal method. Furthermore, a hollow structure Al2O3-supported metallic Ni catalyst (termed Ni–Al2O3–HFA) was synthesized via the Kirkendall effect for the hydrogenation–alkylation cascade reaction by employing as-synthesized Al-MOFs as a carrier for impregnation of Ni(NO3)2·6H2O through further calcination and reduction. Various characterizations (e.g., XRD, HADDF-STEM, H2-TPR) were conducted to reveal the superior performance of the developed Ni–Al2O3–HFA catalyst compared to Ni/Al2O3–IWI (Al2O3 obtained from calcination of Al-MOFs) in cascade reaction between nitroarenes and alcohols. We hope to use the MOF template method via the Kirkendall effect to prepare hollow structure nanocatalysts, which can provide a guideline for the preparation of other hollow materials.
危险品化学品经营许可证（带存储）