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This work investigates the possibility that valuable levulinic acid and sulfonated carbon could be produced in a one-pot reaction. p-Toluenesulfonic acid is used as an acidic catalyst as well as a sulfonating agent in the reaction, and its main effects are determined, depending on the water dosage. Relatively low water dosage is conductive to sulfonated carbon formation with high H+exchange capacity and −SO3H intensity, good carbon framework, improved thermal stability and surface hydrophobicity, and good catalytic activity. In contrast, low water dosage is detrimental to levulinic acid yield. Under optimal reaction conditions, the total carbon utilization ratio of levulinic acid and sulfonated carbon reaches 70%. The sulfonated carbon shows good catalytic activity in the esterification of levulinic acid with ethanol, resulting in a high conversion ratio (93%).

This paper reports the varying water-to-surfactant (ω) ratio in reverse microemulsion on the development of Ni encapsulation in bulk SiO2catalyst for dry reforming of methane. From XRD and TEM analyses, the Ni particle size depends on the water-to-surfactant ratio. It found that an optimized ratio of ω improves the catalytic activity for the dry reforming of methane. The catalyst (Ni-SiO2-ω23) shows 70% CH4conversion and 78% CO2conversion at 700 °C and WHSV of 72000 mLgcat−1h−1operating for 50 h with TOF of 12.6 s−1. It is highly anticipated that the increased fraction of 2:1 nickel phyllosilicate and small Ni particle size contributed to its improved catalytic activity corresponding to the ω ratio. Also, a higher ω value can resist carbon formation in the catalysts, characterized by XRD, TGA, Raman, XPS, and TEM. These results were encouraging that could be applied in similar high-temperature reactions.

High purify oleuropein (81.04% OL) was hydrolyzed by hemicellulase and phenols was existed in the ethyl acetate extract of enzymatic hydrolysate (EAE). The results presented that there were hydroxytyrosol (HT), tyrosol, caffeic acid, 3,4-dihydroxybenzoic acid, 3,4-dihydroxy phenylacetic acid in EAE by HPLC, and HT content was 19.36%. Antioxidant activities (DPPH radical scavenging capacity) were all added as the samples concentration increased, and dose-effect relationships also existed. HT possessed the highest DPPH radical scavenging capacity, followed by Vc, and eugenol, OL, caffeic acid, 3,4-dihydroxy phenylacetic acid and 3,4-dihydroxybenzoic acid.