Effect of pyrolysis temperature on the physical and chemical characteristics of pine wood biochar
Berhane Handiso, Timo Pääkkönen, Benjamin P. Wilson
Abstract
• Varying pyrolysis temperatures offered various biochar physicochemical characteristics. • At higher temperatures, biochar possesses larger carbon and smaller oxygen percentage. • Increasing pyrolysis temperatures increase surface area and enhance porosity. • Different pyrolysis temperatures revealed variations of surface functional groups. Biochar is a useful bioproduct with a wide range of promising applications. The main objective of this study is to investigate the effect of pyrolysis temperatures on the physicochemical properties of biochar produced from pine wood using a slow pyrolysis methodology. Fourier transfer infrared (FTIR) spectroscopy analysis uncovered that the biochar synthesized at the different temperatures selected possessed distinct functional groups. The elemental analysis confirmed that an increase in pyrolysis temperature led to a rise in the carbon (C) concentration, whereas conversely there is a reciprocal decrease in the levels of oxygen (O) and hydrogen (H). Consequently, biochar produced at high temperatures showed low (O/C) and (H/C) fractions. Surface area (gas adsorption) studies indicated that the biochar surface area and pore volume increase at higher pyrolysis temperature. In contrast, the pore size was found to decrease at high temperatures. It was found that increased pyrolysis temperature resulted in reduced biochar yield. Biochar for use in specific applications like as an adsorbent material is ultimately influenced by the pyrolysis temperature. Therefore, it can be concluded that the results of the current study enhances the understanding on the effect of pyrolysis temperature on biochar synthesis and how different parameters can be used to tailor the material characteristics for specific applications.