不同裂解温度对工业大麻生物炭各理化性质的影响

Effects of Different Pyrolysis Temperatures on Physicochemical Properties of Industrial Hemp Biochar

选用田间工业大麻收割后废弃的生物质麻秆和麻根为主要原材料,分别在300、400、500、600℃这4种高温条件下利用马弗炉高温裂解,并通过数字化扫描电子显微学、全自动气体吸附仪、傅里叶红外光谱仪等先进分析仪器,对生物炭的分子结构、形态特征、比表面积等进行了比较分析,探究不同裂解温度对工业大麻生物炭理化性质的影响。结果显示,随着裂解温度的升高,GE和GA的产率减少,平均pH值增加。另外,根据扫描电镜图和BET分析结果显示,由于裂解温度的升高,生物炭的总孔隙体积增大;比表面积和微孔体积均先增后减,平均孔数先减后增,且均在500℃时达到峰值。FTIR分析结果显示,GE和GA这2种生物炭表面的官能团总量均伴随裂解温度的升高而减少,其芳香化程度均逐渐上升。

In this study, the waste biomass hemp stalk and yarn of field industrial hemp after harvest were used as the main raw materials, and muffle furnace was used for high temperature cracking at 300, 400, 500 and 600 ℃. The molecular structu re, morphological characteristics and specific surface area of biochar were compared and analyzed by digital scanning electron microscopy, automatic gas adsorption instrument, Fourier infrared spectrometer and other advanced analytical instruments. The effects of pyrolysis temperature on the physicochemical properties of industrial hemp biochar were investigated. The results showed that with the increase of pyrolysis temperature, the yield of GE and GA decreased, and the average pH value increased.In addition, scanning electron microscopy and BET analysis showed that the total pore volume of carbon increased with the increase of pyrolysis temperature. The specific surface area and micropore volume increased first and then decreased, and the average number of pores decreased first and then increased, reaching the maximum value at 500 ℃. FTIR analysis showed that the total number of functional groups on the surface of GE and GA biochar decreased with the increase of pyrolysis temperature,and the degree of aromatization also increased gradually.