醋酸改性纳米黑碳对Cu^(2+)、Cd^(2+)吸附能力的研究

Adsorption ability of nano-scale black carbon modified by acetic acid for Cu^(2+) and Cd^(2+)

用醋酸对黑碳进行改性,通过改性纳米黑碳(MBC)对Cu2+、Cd2+的吸附/解吸试验,探究MBC对Cu2+、Cd2+的吸附特性及吸附稳定性。结果表明,Cu2+和Cd2+在MBC上的吸附动力学过程可分为快吸附和慢吸附两个阶段,且MBC对Cu2+的吸附效率大于Cd2+。Cu2+和Cd2+在MBC上的吸附等温线均能用Langmuir和Freundlich方程拟合,Cu2+和Cd2+在MBC上的最大吸附量分别为13.513、11.364mg/g,且MBC对Cu2+和Cd2+均为优惠吸附。MBC上Cu2+和Cd2+的解吸量均随着吸附量的增加而增大,易解吸态Cu2+在MBC上的解吸率为6.12%~10.25%,Cd2+为9.58%~11.81%,MBC对Cu2+的吸附稳定性大于Cd2+。将醋酸改性与已有改性方法对比,表明醋酸改性条件温和、能耗低、经济环保,将有很大的研发前景。

Acetic acid was adopted m the paper to modliy black carbon. A surlace-modltlecl nano-partlcle black carbon （MBC） was used as a sorben for Cu^2＋ and Cd^2＋ adsorption. The adsorption-desorption characteristics and sta- bility were investigated by adsorption-desorption experiment. The results were as follows： The adsorption kinetics of Cu^2＋ and Cd^2＋ on MBC was divided into fast and slow adsorption stage , and the adsorption efficiency of Cu^2＋ was better than that of Cd^2＋ .The adsorption isotherms of Cu^2＋ and Cd^2＋ on the MBC fit both the Langmuir and Freundli- ch equations. The maximum adsorption quantities of Cu^2＋ and Cd^2＋ on the MBC were 13.513 mg/g and 11.364 mg/g, which exhibited preferential adsorption. The desorption capacities of Cu^2＋ and Cd^2＋ from the MBC increased with the increase of the adsorption capacities. The easy-desorption percentages of Cu^2＋ and Cd^2＋ were 6.12%-10.25~/oo and 9.58%-11.81% respectively,and the adsorption stability of Cu2~ was better than that of Cd^2＋. Compared with the previous modified methods, nano-black carbon modified by acetic acid was economic and environmental materials, which was modified under mild conditions and low consumption.