pH值对泥煤吸附Ni^(2+)动力学的影响

Effect of pH for Ni^(2+) adsorption kinetics on peat

以泥煤作为研究对象,考察了N i2+在泥煤上的吸附规律。元素分析、红外光谱与热重分析表明,泥煤上起吸附作用的主要基团是分子侧链上的各种含氧官能团:—COOH,—OH,—C O等。采用批次法研究了溶液pH值对N i2+在泥煤上吸附动力学的影响。实验表明:泥煤吸附N i2+的过程可大致分为2个阶段;pH值是影响泥煤吸附的重要因素,随pH值增加N i2+吸附量增大,吸附反应速率也增大。N i2+在泥煤上的吸附动力学过程很好地符合假二级反应模型,为泥煤处理N i2+废水过程提供一定的理论指导。

Taking peat as the object of scientific research, the adsorption mechanism of Ni^2＋ on peat was investigated. The presence of elemental analysis, infrared adsorption band and thermogravimetry supported a significant content of carboxyl groups, --OH groups of primary alcohols, --C =O functional groups in the peat. The influences of pH on kinetics characteristics of nickel adsorption on peat were studied using the method of batch. The results show that the adsorption process of Ni^2＋ on peat is divided into two stages and the reaction is dependent on pH value. The adsorption capacities and adsorption rate increase with the increase of pH value. A reasonable kinetic model, pseudo-second-order model, provides a high degree of correlation with the experimental data for the sorption of nickel onto peat in order to supply the certain instructive theory for treatment of Ni^2＋ wastewater by means of peat.