采用鸡粪热解制备生物炭作为吸附剂,研究了不同热解温度(500、600、700和750℃)制备的生物炭吸附磷的动力学和等温线。结果表明,这4种生物炭对磷的吸附能够较好地用准二级动力学模型来描述,并且随着热解温度的升高,平衡吸附量和吸附速率也随之增加。分别用Langmuir等温方程和Fre-undlich等温方程对试验数据进行拟合,等温吸附过程能较好地用Freundlich吸附等温线描述,表明磷在鸡粪生物炭表面的吸附受多种机制影响。4种生物炭对磷的吸附活化能分别为7.67、12.48、11.02、8.80 kJ/mol,说明吸附过程明显带有物理吸附性质。同时对生物炭吸附去除磷的机理做了初步探讨,即水中的磷可以通过非均质吸附到鸡粪生物炭表面的胶体和纳米MgO晶体上而得到去除。%Using bio-carbon prepared from pyrolysis of chicken manure as materials, the adsorption kinetics and isotherm of phosphate by bio-carbon at different temperatures (500,600,700 and 750℃) were studied. The results showed that the ad-sorption of phosphate followed the pseudo second-order kinetics model. The equilibrium of adsorption capacity and adsorption rate were increased with the increase of pyrolysis temperature. Langmuir and Freundlich models were used to fit experimental data. The Freundlich model could describe the adsorption isotherm better, suggesting that multiple processes controlled the sorption of phosphate by bio-carbon. The adsorption activation energy of bio-carbon at different temperatures were 7.67, 12.48, 11.02, 8.80 kJ∕mol, indicating that it belonged to physics adsorption. The preliminary adsorption mechanism of phos-phate removed by the bio-carbon was studied through heterogeneously processed adsorption onto the colloidal and nano-sized MgO particles on bio-carbon surface.
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