腐殖酸以及共存阳离子对膨润土吸附废水中铅离子的影响

研究了钠基膨润土的理化性质及其对水中铅离子的吸附作用,考查了pH值、共存阳离子浓度、腐殖酸浓度对铅离子吸附的影响,结果表明,钠基膨润土对水中铅离子有较好的吸附效果.铅离子在膨润土上的吸附量随pH值的升高而增加,随共存阳离子浓度的升高而减少,随腐殖酸浓度的升高而增加.从热力学角度探讨了吸附机理,发现钠基膨润土对铅离子的吸附量随温度升高而增大,并且吸附等温线符合Freundlich模型.计算了相关的吸附热力学函数:△H=0.9594kJ/mol, △S=16.611 3kJ/(mol·K).

Effect of humic acid and coexistent cation on the adsorption of Pb (II) in wastewater onto bentonite

Both the physical-chemical properties and adsorption performance for lead of Na-bentonite have been studied in this paper. The results showed that the removal of lead in solution by use of bentonite was effective. The pH, concentrations of coexistent cations and humic acid, which could influence the adsorption process were also studied. The results indicate that the sorption of lead (II) on Na-bentonite increased as pH value increased, and increased with increasing humic acid concentration, while decreased with increasing coexistent cation concentration. The adsorption mechanism was investigated from thermodynamics, and it was founded that the sorption of lead (II) on Na-bentonite increased with increasing temperature and the Freundlich adsorption equation fit to the experimental data excellently. The thermodynamic parameters were calculated: deltaH = 0.959 4 kJ/mol, deltaS = 16.6113 kJ/(mol x K).