Pb(NO3)2与CPC共存对沉积物吸附对硝基苯酚的影响

选取Pb(NO₃)₂、氯化十六烷基吡啶(CPC)、对硝基苯酚为代表污染物,试验了重金属与表面活性剂共存对有机物在沉积物上吸附行为的影响.结果表明:Pb(NO₃)₂的存在减弱了CPC的增强吸附效应,Pb(NO₃)₂和CPC共存对对硝基苯酚的吸附产生拮抗效应.在固定CPC初始浓度不变的情况下,拮抗效应随Pb(NO₃)₂初始浓度增大而加强.同时,拮抗效应也取决于CPC的浓度.当CPC初始浓度小于3 000mg/L(平衡浓度低于临界胶束浓度CMC)时,这种拮抗效应尤为明显;随着表面活性剂浓度的继续增加,拮抗效应减弱,并逐渐趋向于CPC的独立效应.机理探讨表明,共存体系中,Pb²⁺与CPC在同一吸附点位不存在竞争吸附.

Effects of Pb(NO3)2 and Cetylpyridinium Chloride on Sorption of p-Nitrophenol by Sediment

Sorption behavior of p-nitrophenol by sediment in the presence of both cetylpyridinium chloride(CPC) and Pb(NO₃)₂ were investigated.The concurrence of Pb(NO₃)₂ inhibited the enhancement of sorption induced by CPC.The removal effect of p-nitrophenol from sediment by compounding of CPC and Pb(NO₃)₂ presented antagonistic effect.At a given concentration of CPC,the antagonistic effect increased with increasing of the initial concentration of Pb(NO₃)₂.The antagonistic effect was also dependent on CPC concentrations.At the initial concentration below(3 000)(mg/L)(the equilibrium concentration was below CMC),the antagonistic effect was especially significant.With the increase of the concentration of CPC,the antagonistic effect decreased gradually.Especially at the higher concentration above CMC,the effect went to be an independent effect just induced by CPC.In addition,the study also indicate that Pb²⁺ and CPC may not compete for the same adsorption sites.