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The conversion of biomass into bio-oil using fast pyrolysis technology is one of the most promising alternatives to convert biomass into liquid products. However, substituting bio-oil for conventional petroleum fuels directly may be problematic because of the high viscosity, high oxygen content, and strong thermal instability of bio-oil. The focus of the current research is decreasing the oxygen and polymerization precursor content of the obtained bio-oil to improve its thermal stability and heating value. Catalytic fast pyrolysis of corncob with different percentages (5, 10, 20, and 30% by volume) of fresh fluidized catalytic cracking (FCC) catalyst (FC) and spent FCC catalyst (SC) in bed materials was conducted in a fluidized bed. The effects of the catalysts on the pyrolysis product yields and chemical composition of the bio-oil were investigated. A greater catalyst percentage lead to a lower bio-oil yield, while a lower catalyst percentage lead to little change of the composition of the bio-oil. The best percentages of FC and SC were 10 and 20%, respectively. FC showed more catalytic activation in converting oxygen into CO, CO 2 , and H 2 O than SC, but the oil fraction yield with FC was remarkably lower than that with SC because of more coke formation. The gas chromatography/mass spectrometry (GC/MS) analysis of the collected liquid in the second condenser showed that the most likely polymerization precursors, such as 2-methoxy-phenol, 2-methoxy-4-methyl-phenol, 4-ethyl-2-methoxy-phenol, 2-methoxy-4-vinylphenol, and 2,6-dimethoxyphenol decreased, while monofunctional phenols, ketones, and furans increased compared to that in the noncatalytic experiment. The hydrocarbons increased with the increase of the catalyst percentages, and this contributed to the decrease of the oxygen content of the bio-oil. Multi-stage condensation achieved a good separation of the oil fraction and water.

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In this communication, poly(lactic acid) nanofibers have been fabricated by electrospinning and then poly(lactic acid) (PLA) based nanocomposites have been prepared by accumulating anticancer drug daunorubicin on PLA nanofibers combined with TiO2 nanoparticles. Our atomic force microscopy (AFM) and laser-scanning confocal microscope (LSCM) studies demonstrate that the respective drug molecules could be readily self-assembled on the surface of the blends of nano-TiO2 with PLA polymer nanocomposites, which could further efficiently facilitate the drug permeation and accumulation on the target leukemia K562 cells. Besides, the respective new nanocomposites have good biocompatibility, ease of surface chemistry modification and very high surface area, which may afford the possibility for their promising application in pharmacology and biomedical engineering areas.

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