Morphology, pore size distribution, and nutrient characteristics in biochars under different pyrolysis temperatures and atmospheres
- 162 Downloads
To evaluate the agronomic potential of biochar, we prepared a series of biochars using rice straw waste under the limited oxygen cracking condition (CO2 or N2) and the different pyrolysis temperatures including 300, 400, 600, and 800 °C. The results showed that morphology structure, specific surface area, pore size distribution, and element contents of the biochars were superior to the biochars prepared under traditional inert atmosphere (N2) and the same four pyrolysis temperatures. In comparison with the rice straw, pore structure of biochars was mainly mesoporous and more developed, average pore size decreased, and BET-specific surface area increased with the increase of temperature from 300 to 800 °C. Biochars distributed abundant mesopores and macropores under 400 and 600 °C; the maximum macropores of the biochar were shaped under 600 °C. Concentration of phosphorus (P) and potassium (K) increased significantly with increasing temperature, while that of nitrogen (N) first increased and then decreased and reached a maximum at 400 °C. In addition, taking these physiochemical properties into consideration, we drew a conclusion that the optimum quality biochar could acquire under the work conditions of 400 °C and CO2 atmosphere, which was supposed to provide theoretical guidance for biochar returning to soil.
KeywordsCO2 atmosphere Biochars Nutrient content Pore structure
This study was supported by the National Natural Science Foundation of China (No. 41571283) and National Key Research and Development Program of China (2016YFD0800702).
- 3.Sohi S (2013) Biomass, bioenergy and the sustainability of soils and climate: what role for biochar? In: EGU general assembly conference. EGU general assembly conference abstractsGoogle Scholar
- 4.Deng X (2012) Effects of Giant reed biochar on nitrogen bioavailability in the agricultural soil. Ocean University of China, Qingdao (in Chinese) Google Scholar
- 13.Jeffery S, Bezemer TM, Cornelissen G, Kuyper TW, Lehmann J, Mommer L et al (2013) The way forward in biochar research: targeting trade-offs between the potential wins. Glob Change Biol Bioenergy 7:11–13Google Scholar
- 21.Verheijen F, Jeffery S, Bastos AC, van der Velde M, Diafas I (2010) Biochar application to soils. A critical scientific review of effects on soil properties, processes and functions. European Commission Joint Research Centre, Institute for Environment and Sustainability, Luxemburg, p 149Google Scholar
- 30.Jian MF, Gao KF, Yu HP (2016) Effect of different pyrolysis temperatures on the preparation and characteristics of bio-char from rice straw. Acta Sci Circumst 36:1757–1765 (in Chinese) Google Scholar
- 34.Li L, Lu YC, Liu YY, Sun HW, Liang ZY (2012) Adsorption mechanisms of cadmium(II) on biochars derived from corn straw. J Agro-Environ Sci 31(11):2277–2283 (in Chinese) Google Scholar
- 39.Lehmann J, Joseph S (2009) Biochar for environmental management: science and technology. Earthscan 25(1):15801–15811Google Scholar
- 52.Lin XF, Zhang J, Yin YS (2009) Study on fractal characteristics of biomass chars. Biomass Chem Eng 43:10–12Google Scholar