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The low temperature and high efficiency cracking oxidation of organic solid waste over the bifunctional catalyst with both acidity and oxidizing property is an environmentally attractive technology. In this study, the reaction mechanism and kinetics behavior of waste polypropylene (PP) during catalytic cracking oxidation processes were investigated utilizing thermo-gravimetry (TG), differential scanning calorimetry, TG−mass spectrometric, and in situ Fourier transform infrared (in situ FTIR) spectroscopy. PP was cracked into low-molecular weight organic substances (ester, ketone, etc.) over acid sites, which were further oxidized to CO 2 and H 2 O over oxygen vacancy in the Mn 2 O 3 /HY catalyst. The kinetics of catalytic cracking oxidation of pure PP and PP over different model catalysts was analyzed by Gauss-Peak function and the distributed activation energy model (DAEM). The catalytic oxygenation apparent activation energy (E) values of pure PP and PP over Mn 2 O 3 , HY, and Mn 2 O 3 /HY catalysts were 130−190 kJ/mol, 200−618, 108−228, and 41−99 kJ/mol, respectively. DAEM expressed appropriately the various changing trends of E in the reaction process. This theoretical basis of the catalytic cracking oxidation process of polymers would provide a reference for the design and optimization of the reactor and application upgrade of engineering.

A series of Mg/Ca modified HZSM-5 zeolite catalysts were prepared by the impregnation method for catalytic coupling of CH3Cl to light olefins. The catalysts were characterized using X-ray diffraction , N2 adsorption–desorption, NH3 temperature programmed desorption, and pyridine-IR techniques. Results showed the Mg/Ca modification substantially reduced the strong Brønsted acid amount and greatly improved light olefin selectivity. The Mg-rich catalysts were more inclined to generate C3H6 and C4H8 due to less strong acid sites but shorten the lifetime due to smaller pore size. The 5Ca2Mg-HZ catalyst offered the best performance with 87.2% total olefin selectivity and 99% CH3Cl conversion over 58 h. Coke analysis revealed all the modified catalysts had similar coking behaviors while the short-lived catalysts showed an early drop in surface area owing to the blocked channels. The deactivation–regeneration experiments showed the 5Ca2Mg-HZ catalyst also had good reproducibility.

Aqueous Zn‐metal batteries (AZMBs) have gained great interest due to their low cost, eco‐friendliness, and inherent safety, which serve as a promising complement to the existing metal‐based batteries, e.g., lithium‐metal batteries and sodium‐metal batteries. Although the utilization of aqueous electrolytes and Zn metal anode in AZMBs ensures their improved safety over other metal batteries meanwhile guaranteeing their decent energy density at the cell level, plenty of challenges involved with metallic Zn anode still await to be addressed, including dendrite growth, hydrogen evolution reaction, and zinc corrosion and passivation. In the past years, several attempts have been adopted to address these problems, among which engineering the aqueous electrolytes and additives is regarded as a facile and promising approach. In this review, a comprehensive summary of aqueous electrolytes and electrolyte additives will be given based on the recent literature, aiming at providing a fundamental understanding of the challenges associated with the metallic Zn anode in aqueous electrolytes, meanwhile offering a guideline for the electrolytes and additives engineering strategies toward stable AZMBs in the future.