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Adsorption process is considered to be the most promising alternative for the CO2 capture to the traditional energy-intensive amine absorption process, and the development of feasible and efficient CO2 adsorbents is still a challenge. In this work, the NiO@USY (ultrastable Y) composites with different NiO loadings were prepared for the CO2 adsorption using Ni(NO3)2 as the precursor. The composites were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, nitrogen adsorption–desorption test, scanning electron microscopy analysis, and thermogravimetric analysis, and were evaluated for the CO2 adsorption capacity, CO2/N2 adsorption selectivity and CO2 cycle adsorption capacity. The characterization results show that after the activation at 423 K, the Ni(NO3)2 species were well dispersed into the surface of zeolite USY, and after the further activation at 823 K, Ni(NO3)2 could be converted into highly dispersed NiO. The adsorption results show that the presence of the active component NiO plays an important role in improving the CO2 adsorption performance, and the NiO@USY composite with a NiO loading of 1.5 mmol·g−1 USY support displays a high adsorption capacity and adsorption selectivity for CO2, and shows a good cycle stability. In addition, the Clausius–Clapeyron equation was used to evaluate the isosteric heat of adsorption of CO2 on the NiO(1.5)@USY composite, and the heat of adsorption was 17.39–38.34 kJ·mol−1.

Cinnamon essential oil with many bioactivities is an important raw material for the production of various chemicals, and the conventional hydrodistillation (HD) for cinnamon oil extraction always require a longer extraction time. In this work, ultrasound-assisted hydrodistillation extraction (UAHDE) technique was employed to enhance the extraction efficiency of essential oils from cinnamon barks. The parameters with significant effects on the essential oil extraction efficiency (ultrasound time, ultrasound power, extraction time, liquid–solid ratio) were optimized, and the proposed UAHDE was compared with the conventional HD extraction in terms of the extraction time, extraction yield, and physicochemical properties of extracted oils. Compared to the HD extraction, the UAHDE resulted in a shorter extraction time and a higher extraction yield. Using GC–MS analysis, the UAHDE provided more valuable essential oil with a high content of the vital trans-cinnamaldehyde compounds compared with the HD. Scanning electron micrograph (SEM) confirmed the efficiency of ultrasound irradiation for cinnamon oil extraction. In addition, the analysis of electric consumption and CO2 emission shows that the UAHDE process is a more economic and environment-friendly approach. Thus, UAHDE is an efficient and green technology for the cinnamon essential oil extraction, which could improve the quantity and quality of cinnamon oils.

A seed-induced method was applied to synthesize a series of ZSM-5 aggregates using silicalite-1 (S-1) as seeds. The samples were characterized by several techniques and studied in the methanol-to-gasoline (MTG) conversion reaction in a continuous fixed-bed reactor. The results showed that the molar ratios of Na2O/SiO2 and H2O/SiO2 in the precursors had great effects on the physicochemical and catalytic properties. The ZSM-5 aggregates with the highest crystallinity, external surface areas, micropore volumes, mesopore volumes and small primary crystal and aggregate sizes, obtained with the molar composition of 0.12Na2O–1SiO2–0.02Al2O3–25H2O-0.01Seed in the precursor, exhibited the highest stability.