摘要
在不同热解温度、热解时间及配比下,利用生活污泥与小麦秸秆共热解制备污泥基生物炭(WB),研究了不同条件对WB吸附性能的影响,并以吸附性能为评价指标,应用响应面分析法优化了WB的最佳工艺条件,并研究了最佳WB对水溶液中Cr(VI)的吸附规律。结果表明:1)热解温度、热解时间和配比对WB吸附能力均有显著影响;2)制备WB的最佳热解温度、热解时间、配比分别为503.19℃、120 min、m(麦秆)∶m(污泥)=1.2;3)Langmuir模型和Freundlich模型都能很好地表征WB对Cr(VI)的吸附特征,二级动力学模型可以更好地解释WB对Cr(VI)的吸附机制。
Sludge-based biochars(WB) were prepared by co-pyrolysis of sludges and wheat straws under different pyrolysis temperatures, times and ratios, and the effect of different pyrolysis conditions on the adsorption properties of WB was studied, besides, optimum process for the preparation of WB was optimized by the response surface analysis method, and the adsorption law of optimum WB on Cr(VI) in aqueous solution was investigated. The results showed that: 1) pyrolysis temperature, pyrolysis time and ratio had significant influence on the adsorption capacity of WB; 2) the optimum pyrolysis conditions for preparing WB were 503.19 ℃, 120 min, and 1.2(m(straw)∶m(sludge), dry weight); 3) both the Langmuir and the Freundlich models could well characterize the adsorption characteristics of WB on Cr(VI), and the second kinetics model could explain the adsorption of Cr(VI) better.
引文
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