玉米秸秆通过热解可得到具有较丰富孔隙结构和较高比表面积的生物炭。然而原始生物炭存在吸附性能较差和矿质养分含量低等缺点。以MgCl₂·6H₂O为活化剂、磷酸盐的吸附量为指标,通过单因素试验和响应面试验对热解温度(A)、保温时间(B)和活化剂浓度(C)等热解改性条件进行优化,制备性能优良的改性生物炭。结果表明,各因素的影响显著性顺序为C > A > B,其中AB及AC交互作用显著。在热解温度为505℃、保温时间为96 min以及活化剂浓度为1.2 mol/L的条件下制备得到对磷酸盐吸附量(25.425 mg/g)最好的改性生物炭。

Biochar with rich pore structure and high specific surface area can be obtained through the pyrolysis of corn stalk.However,the original biochar has the disadvantages of poor adsorption performance and low mineral nutrient content.Using MgCl₂·6H₂O as activator and phosphate adsorption as index,the pyrolysis modification process conditions,such as pyrolysis temperature (A),holding time (B) and activator concentration (C),are optimized via single factor test and response surface methodology,and the modified biochar with excellent performance is hence obtained.Results show that the order of significance of each factor is C > A > B,and the interactions between A and B,A and C are more significant.The modified biochar with the best phosphate adsorption capacity (25.425 mg·g^-1) is prepared under the conditions that pyrolysis temperature is 505℃,holding time is 96 min and activator concentration is 1.2 mol·L^-1.

岳佳怡(2001-),女,本科生,主要从事多孔炭的制备及性能研究,15991468446,jyyue3193@163.com;谢贵明(1984-),男,博士,副教授,研究方向为聚合物功能材料,gmxie@gzu.edu.cn。