热解温度对长、短绒棉基生物炭性能影响

Effect of temperature on the properties of biochar prepared from long and short staple cotton straw

采用南疆地区生产的长绒棉和短绒棉棉秆为原料制备生物炭,研究温度对棉秆基生物炭性能影响。主要测试了所制备样品的产率、pH值、电导率、灰分、碘吸附值、持水能力和比表面积。结果表明,2种原料所制备的生物炭产率均随温度的升高而降低,长绒棉与短绒棉棉秆均在300℃时出现最高产率,分别是45.1%和42.7%;pH值和电导率均随温度的升高而增大,长绒棉棉秆基生物炭的pH值、灰分和电导率在不同温度下均低于短绒棉棉秆基生物炭;碘吸附值和持水能力均随温度发生波动;400℃退火3 h所制备样品的平均孔径为13.9 nm,最可几孔径为3.83 nm。

Biochars were prepared based on long staple cotton and short staple cotton from the southern region of Xinjiang, and the effect of temperature on the properties of biochar based on cotton stalk was studied. The pH value, conductivity, ash content, iodine adsorption value, water holding capacity and specific surface area of the samples were tested. The results showed that the yield of two biochar decreased with the increase of temperature. The highest yield of long staple cotton and short staple cotton were 45.1% and 42.7% at 300℃, respectively. The pH value, ash content and conductivity increased with the increase of temperature. The pH value, ash content and conductivity of long staple cotton were lower than those of cotton linter under different temperatures. Both the iodine adsorption value and water holding capacity fluctuate with the temperature. The average pore size of the samples prepared by carbonization at 400 ℃ for 3 h was 13.9 nm, and the most probable pore size was 3.83 nm.