改性大豆秸秆生物炭对咪唑乙烟酸的吸附

700℃热解温度下制备大豆秸秆生物炭，并利用酸、碱、氨基修饰和铁磁化4种方法对其进行改性，比较4种改性大豆秸秆生物炭对咪唑乙烟酸的吸附性能及机制，同时考察溶液pH值、温度和添加量对吸附效果的影响，并探讨了改性大豆秸秆生物炭在提高土壤对咪唑乙烟酸吸附固定能力中的应用效果.结果表明，在pH值为2~4的酸性环境中，改性大豆秸秆生物炭吸附效果更好；相对于其他3种方法，铁磁化改性大豆秸秆生物炭对咪唑乙烟酸具有更好的吸附性能，吸附符合准一级动力学模型和Langmuir模型，且Langmuir模型拟合结果表明其对咪唑乙烟酸的最大吸附量可达338.785mg/g；添加1%铁磁性改性大豆秸秆生物炭的土壤对咪唑乙烟酸吸附量提高为对照组的2.37倍.

Sorption characteristics and mechanism of imazethapyr by modified soybean straw biochar

Soybean straw biochar was prepared at 700℃ and modified by four methods including acid, alkali, amino modification, and iron magnetization. The sorption performance and mechanism of four modified biochar for imazethapyr were compared, and the effect of pH, temperature, and biochar dosage on the sorption amounts were discussed. In addition, the performance of modified soybean straw biochar for the sorption and fixation capacity of imazethapyr in soil was investigated. Modified soybean straw biochar had better sorption performance in the acidic environment with a pH value of 2~4. Comparing with the other three modified biochars, iron-magnetized biochar exhibited a higher sorption efficiency on imazethapyr. And its sorption behavior was better fitted by the pseudo-first-order kinetics and Langmuir model. The fitted Langmuir model indicated that the maximum sorption capacity of iron-magnetized biochar on imazethapyr reached 338.785mg/g; The sorption capacity for imazethapyr in the soil with 1% iron-magnetized biochar was 2.37 times higher than that without iron-magnetized biochar.