木质素高温炭化制备导电焦炭特性研究

以木质素为原料,对高温炭化制备的焦炭进行酸洗,得到导电性及孔隙结构良好的焦炭,研究炭化温度对焦炭特性的影响.通过X射线衍射（XRD）、扫描电镜（SEM）、傅里叶红外光谱（FTIR）以及N2吸附仪(BET)对焦炭性能进行表征.实验结果表明,炭化温度在800 ℃以上时,木质素中的Na2CO3经高温分解成Na2O和CO2,析出的CO2可能会对焦炭孔隙起活化作用.随着炭化温度的升高,焦炭微孔的体积分数减小,中孔的体积分数增加,孔径主要集中在2～6 nm.炭化温度为1 200 ℃,酸洗后的焦炭电阻率可以降至0.076 Ω·cm.

Characteristics of electrically conductive charcoal prepared by high temperature carbonization of lignin

Charcoal with good electric conductivity and developed pore structure was prepared by high temperature carbonization followed by HCl treatment using lignin as raw material. The properties of charcoal from different carbonization temperature were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier infrared spectrum (FTIR) and Brunauer-Emmett-Teller (BET) method. Experimental results indicated that charcoal activation took place through gasfication of CO2 produced from Na2CO3 during carbonization at over 800 ℃. Mesopore volume fraction increased and micropore volume fraction decreased with the increase of carbonization temperature, and the pore size mainly ranged from 2 nm to 6 nm. The electrical resistivity of charcoal could reduce to 0.076 Ω·cm at 1 200 ℃.