【摘要】 研究了玉米芯生物炭剂对土壤中2,4-D的吸附性能,并探讨了影响吸附的因素和吸附机理.结果表明:生物炭可使土壤对2,4-D的吸附容量显著增大.吸附结果用Freundlich和Redlich-Peterson方程都可以较好地拟合(R2>0.95).60 h后,与对照土壤相比,添加质量分数为0.5%生物炭的土壤对2,4-D的最大吸附量从20.83μg·g-1升高到58.82μg·g-1.吸附动力学研究表明,伪二级动力学速率方程对土壤吸附2,4-D的过程拟合效果较好(R2>0.99),优于一级动力学速率模型;p H和温度对土壤中2,4-D的吸附影响显著,p H接近3.1和40℃的水浴环境更利于添加生物炭的土壤对2,4-D的吸附.玉米芯生物炭可作为原位修复剂吸附土壤中的2,4-D,从而降低土壤中有机污染物的迁移性和生物有效性.更多还原

【Abstract】 This work investigates the adsorption of 2,4-Dichlorophenoxyacetic( 2,4-D) in spiked soil with biochar derived from maize straw. The adsorption capacity of soil was enhanced by biochar application. According to equation linear fitting of Langmuir,Freundlich and Redlich-Peterson isotherms,when biochar weight was 0. 5%,the theoretical uptake of 2,4-D reached 58. 82 μg·g- 1( initial 2,4-D concentration of 10 mg·L- 1) within 60 h. High correlation coefficients( R2> 0. 99) suggest that pseudo-second order kinetic model appropriately described the adsorption of 2,4-D onto biocharadded soil. Further analysis indicated that 2,4-D adsorption in soil is positively influenced by reaction condition such as p H value and temperature. A p H value of 3. 1 and temperature of 40 ℃ suitably ensured the adsorption capacity of biochar-added soil. Results from this study suggest that biochar effectively remediates 2,4-D-contaminated soil in situ.更多还原