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To maximize selective condensation of organics that are of known higher commercial value and to investigate the effects of selective condensation on bio-oil characterization, pine sawdust was pyrolyzed in a 1-5 kg/h bench-scale fluidized-bed reactor. In the experiments, the selective condensers and electrostatic precipitator were used to condense the pyrolysis vapors. In addition, the characterization of bio-oils, gases, and biochar was investigated. The results showed that the total bio-oil, gases, and char yields were 41.5, 43.3, and 15.2%, respectively, and 86.2 wt % water steam was condensed in condenser 1. The bio-oil condensed in the later condensers has a lower water content, higher pH value, higher heating value, and higher kinetic viscosity compared to the first one. Analysis of the 1, 4, and 5 bio-oils with gas chromatography-mass spectrometry (GC-MS) showed that 102 types of chemical compounds were detected and most of the compounds were condensed at different condensers. Therefore, the selective condensation is useful to separate the water and chemical compounds from bio-oil compared to direct contacting condensing. The gas products were mainly CO, H 2 , CO 2 , CH 4 , and C 2 -C 4 . Char characteristics were determined by ultimate analysis, Fourier transform infrared (FTIR) spectrometry, and scanning electron microscopy (SEM) methods. A lot of bonds, such as -NH-, -CH-, -CdC-, -CH 3 , and -C-O-C-, were found in the char samples. It was observed that the surface morphology of the pine particle changed after pyrolysis, and it became thinner and shrank. The thermal decomposition of chemical bonds and the melting of some compounds can break the chemical bonds of the original material, and the chemical bonds with lower bond energies break with priority. The research has provided a useful reference for biomass fast pyrolysis.

Slow kinetics and low specific capacity of graphite anode significantly limit its applications in the rapidly developing lithium-ion battery (LIB) markets. Herein, we report a carbon framework anode with ultrafast rate and cycling stability for LIBs by nitrogen and phosphorus doping. The electrode structure is constructed of a 3D framework built from 2D heteroatom-doped graphene layers via pyrolysis of self-assembled supramolecular aggregates. The synergistic effect from the nanostructured 3D framework and chemical doping (i.e., N-and P-doping) enables fast kinetics in charge storage and transport. A high reversible capacity of 946 mAh g −1 is delivered at a current rate of 0.5 A g −1 , and excellent rate capability (e.g., a capacity of 595 mAh g −1 at 10 A g −1 ) of the electrode is shown. Moreover, a moderate surface area from the 3D porous structure contributes to a relatively high initial Coulombic efficiency of 74%, compared to other graphene-based anode materials. The electrode also demonstrates excellent cycling stability at a current rate of 2 A g −1 for 2000 cycles. The synthetic strategy proposed here is highly efficient and green, which can provide guidance for large-scale controllable fabrication of carbon-based anode materials.

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