摘要
为了提高杨树炭对水中Ni(Ⅱ)的吸附能力,采用氢氧化钠对其进行改性处理。通过杯罐实验,研究了pH对吸附效果的影响,以及吸附动力学和吸附等温线。结果表明,溶液pH值对碱改性杨树炭吸附Ni(Ⅱ)效果的影响明显,随着溶液pH从3.0提高到7.0,Ni(Ⅱ)的去除率逐渐增大。碱改性杨树炭对Ni(Ⅱ)的吸附过程符合准二级动力学规律。Freundlich等温线模型和Langmuir等温线模型均可以很好地描述碱改性杨树炭对Ni(Ⅱ)的等温吸附行为。
In order to improve the adsorption capacity of Ni( Ⅱ), poplar charcoal was modified with sodium hydroxide. The effect of pH, adsorption kinetics and adsorption isotherm were investigated experimentally using batch reactor. The results showed that pH had obvious effect on adsorption capacity. The removal rate of Ni( Ⅱ) increased with the increase of pH value from 3.0 to 7.0. It was found that the adsorption kinetics of Ni( Ⅱ) by alkali modified poplar charcoal was in line with the quasi-second-order kinetic equation. Both of Freundlich isotherm model and Langmuir isotherm model could well describe the isothermal adsorption behavior of Ni( Ⅱ) on alkali modified poplar charcoal.
引文
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