制备条件对不同原料生物炭理化性质的影响

Effect of Preparation Conditions on Physicochemical Properties of Biochar from Different Raw Materials

本文选取水稻秸秆(BR)、小麦秸秆(BW)、玉米秸秆(BC)为原料,在300℃、400℃、500℃温度下制备成生物炭,并进行了产率、灰分、元素分析及官能团测定。结果表明,随着制备温度的升高,生物炭产率呈下降趋势,灰分含量呈上升趋势,由高到低依次为BR>BW>BC;不同制备温度下,3种生物炭中元素含量C>O>H>N,随着温度的升高,C元素含量增加,H、O、N元素含量减少,H/C、O/C均呈现下降趋势;随着制备温度的升高,3种生物炭的官能团总量呈现下降趋势,而碱性官能团数量呈现上升趋势,较高裂解温度有利于碱性官能团的形成。另从原料上看,BC官能团总量大于BR和BW。原材料和制备温度对生物炭的理化性质均有影响。

In this paper,rice straw(BR),wheat straw(BW)and corn straw(BC)are selected as raw materials to prepare biochar at 300℃,400℃and 500℃,and the yield,ash content,element analysis and functional group determination are determined.The results show that with the increase of preparation temperature,the yield of biochar decreased,while the ash content increased,and the order from high to low is BR>BW>BC.At different preparation temperatures,the content of C>O>H>N in the three kinds of biochar.With the increase of temperature,the content of C increased,while the content of H,O and N decreased,and both H/C and O/C show a decreasing trend.With the increase of preparation temperature,the total amount of functional groups of the three kinds of biochar show a decreasing trend,while the number of alkaline functional groups show an increasing trend.Higher pyrolysis temperature is beneficial to the formation of alkaline functional groups.In addition,from the perspective of raw materials,the total amount of BC functional groups is greater than that of BR and BW.The raw materials and preparation temperature have an impact on the physical and chemical properties of biochar.