Pine cone (PC) is a potential biomass energy source and is rich in nonstructural substances (NSS). To understand the impact of these NSS on the pyrolysis behavior and its products, in this study, phenol alcohol extraction was used for the separation of NSS from PC (the PC after separation of NSS was labeled as A-PC), and then thermogravimetric analysis −Fourier transform infrared and PY-gas chromatography/MS detection techniques were used to conduct a systematic comparison of the thermal degradation behaviors and kinetics parameters of PC and A-PC. Results showed that the N content of PC was higher than that of other biomass, and the activation energies of PC and A-PC generally decreased at first and then increased as the conversion rate increased. Furthermore, the activation energy of PC decreased with conversion rates in the range of 0.25–0.30, while A-PC lagged significantly behind PC. On the other hand, the maximum absorption peak of CH4 for PC was higher than that of A-PC, and the maximum absorption peak of CO2 was quite the opposite. After extracting NSS from the PC, its activation energy was significantly increased.
Finding low-cost and environmentally friendly precursors that can maintain their electrochemical attraction natural texture properties while obtaining hierarchical porous carbons with high electrochemical performance is desirable for offering a leap forward in industrial applications. However, phenomena associated with the high microporosity of porous carbon remain. Herein, the protective effect of hydrothermal methods and the micropore-forming ability of KOH were used. The as-synthesized porous carbon (PC-1) holds the natural texture property (the retention of texture property with apertures higher than 2 nm was up to 80%) and achieves three-dimensional (3D) architecture with hierarchical structures accompanied by an ultrahigh specific surface area (3559.45 m2/g). Benefiting from its texture properties, PC-1 possesses a high specific capacitance of 288.75 F/g at 0.5 A/g, excellent rate capability as high as 223.72 F/g at 10 A/g, and remarkable conductivity in a three-electrode system with a 6 M KOH electrolyte. In view of its environment friendliness, low cost, and excellent specific capacitance, PC-1 has promising applications in high-performance supercapacitors.
Using apricot shell lignin as a raw material, the effects of torrefaction temperatures (160, 200, 240, and 280 °C) on the properties of torrefied products were studied, and the catalytic pyrolysis experiments of the torrefied lignin under the HZSM-5 catalyst were carried out. The results showed that the oxygen content in lignin was greatly reduced and the higher heating values (HHV) gradually increased, the absorption peak of oxygen-containing functional groups gradually became weaker, and the content of the β-O-4 bond gradually decreased. At 280 °C, the C/O ratio reaches the maximum value of 2.17, and the calorific value increases to 24.22 MJ/kg. The removed oxygen element is converted into oxygen-containing components in the gas (mainly CO2 and H2O) and liquid products (mainly guaiacol phenol). After catalytic pyrolysis of torrefied lignin, it was found that with the increase of torrefaction temperature, the relative content of aromatics increased first and then decreased slightly; the aromatics reached the maximum value of 60.63% at 240 °C; acids decreased significantly; ketones, aldehydes, and furans changed little; and torrefaction played a positive role in the conversion of lignin to aromatics.