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Hierarchical porous activated carbon (AC) was obtained from corn stalk pith with a hierarchical macroporous nature, which is composed of cells of soft and spongy texture. The high specific surface area (2495 m 2 g-1) of the activated carbon (AC) was produced by the activation of corn stalk core (CSC) using potassium hydroxide at 700 °C. SEM, TEM and XRD were used to test the microstructure and crystallographic orientation of the carbon samples. The cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy were measured based on CSC-700. This sample had relatively low inner resistance of 1.0 Ω. The specific capacitance was 323 F g-1 in 6 mol L-1 KOH electrolyte at a current density of 0.1 A g-1 , and it still maintained very good cyclic stability with capacitance retention ratio of 97.9% (from 265.0 to 262.4 F g-1) at current density of 1.0 A g-1 for 1000 cycles.

14Rod-shape porous carbon was prepared from aniline modified lignin via KOH activation and 15 used as electrode materials for supercapacitors. The specific surface area, pore size and shape 16 could be modulated by the carbonization temperature, which significantly affected the 17 electrochemical performance. Unique rod-shape carbon with massive pores and a high BET 18 surface area of 2265 m 2 g -1 were obtained at 700 in contrast to irregular morphology created at 19 other carbonization temperatures. In 6 mol L -1 KOH electrolyte, a specific capacitance of 336 F 20 g -1 , small resistance of 0.9 Ω and stable charge/discharge at current density of 1 A g -1 after 1, 000 21 cycles were achieved using rod-shape porous carbon as electrodes in an electrical double layer 22 capacitor.23 a Z R. Gu Tel./fax: + 1 605 688 5372. from abundant, renewable biomass feedstock can be produced sustainably at low cost 47 [15]. So far, carbon materials derived from biomass such as rice husk, coffee grounds, grape seed, 48 cornstalk, banana peel [16-20], have been explored as electrode materials in EDLC and 49promising electrochemical performance has been demonstrated. 50Recent research showed that introducing nitrogen into activated carbon could induce additional 51 pseudo-capacitance via reversible redox reactions and improve the wettability between the 52 electrodes and electrolytes [21]. As a result, the capacitance performance of EDLC was greatly 53 promoted. Therefore, biomass derived carbon materials with nitrogen may be promising 54 electrode materials for EDLC. Since biochar typically contains low nitrogen content, we 55 hypothesize that combination of nitrogen rich compounds with biomass will lead to biochar with 56 high nitrogen content. Furthermore, there may be opportunities to tune the physicochemical 57 properties of the nitrogen rich biochar, such as morphology, surface area, and conductance. 58Regarding the source of nitrogen, aniline appears a promising candidate because it is easy to 59 polymerize, and the polymer can be grown into different shapes such as wires, tubes and spheres 60 [22-24] by controlling the synthetic conditions. 61 Herein, we present aniline modified lignin as the raw materials to prepare rod-shape porous 62 carbon as EDLC electrode materials. It is shown that the chemical activation plays a key role in 63 achieving large specific surface area, uniform pore size distribution and good conductivity, 64 which lead to excellent electrochemical performance. 65 2. Experimental 66 2.1 Preparation of activated carbon 67 Solvent lignin (3 g), aniline (1.5 ml) and 30 ml ethanol were added into a flask with 30 ml 68 ethanol, followed by stirring at 80 until the ethanol was evaporated. Then the mixture was 124 temperature. At high temperatures, the activation agent KOH reacted with carbon, producing 125 gases (CO, H 2 O and CO 2 ), forming pores and leaving behind potassium salts (K, KOH and 126 K 2 CO 3 ) [26]. The interconnected cavities in the porous carbon might serve as reservoirs for the 127 electr...

Catalytic cracking of camelina oils to hydrocarbon fuels over ZSM-5 and ZSM-5 impregnated with Zn 2+ (named bifunctional catalyst) was individually carried out at 500 o C using a tubular fixed-bed reactor. Fresh and used catalysts were characterized by ammonia temperature-programmed desorption (NH 3 -TPD), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and nitrogen isothermal adsorption/desorption micropore analyzer. The effect of catalysts on the yield rate and qualities of products was discussed. The loading of Zn 2+ to ZSM-5 provided additional acid sites and increased the ratio of Lewis acid site to Brøn-sted acid site. BET results revealed that the surface area and pore volume of the catalyst decreased after ZSM-5 was impregnated with zinc, while the pore size increased. When using the bifunctional catalyst, the pH value and heating value of upgraded camelina oils increased, while the oxygen content and moisture content decreased. Additionally, the yield rate of hydrocarbon fuels increased, while the density and oxygen content decreased. Because of a high content of fatty acids, the distillation residues of cracking oils might be recycled to the process to improve the hydrocarbon fuel yield rate.

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