邻苯二甲酸酯及邻苯二甲酸在碳管上的吸附

以邻苯二甲酸(PA)和邻苯二甲酸二乙酯(DEP)为目标污染物,碳纳米管(CNTs)为吸附剂,通过不同pH值条件下单、双溶质的吸附实验,结合能量分布理论,分析PA对DEP在CNTs上的竞争和取代吸附.结果表明,在同一pH值下,DEP在CNTs上的吸附性强于PA.对于DEP,pH值改变导致的CNTs分散稳定性的变化是影响其...

Sorption of phthalic acid esters and low-molecular weight acid on carbon nanotubes

Phthalic acid (PA) and diethyl phthalate (DEP) were the target pollutants, and carbon nanotubes (CNTs) were used as sorbents. Based on the sorption site energy distribution theory, the competitive and displacement sorption of DEP by PA on CNTs were analyzed by the single- and dual-solute sorption experiments under different pH conditions. Sorption intensity of DEP on CNTs was stronger than that of PA under specific pH condition. For the sorption of DEP on CNTs, the dispersion stability of CNTs affected by the solution pH was the dominant factor to the sorption process. For the sorption of PA, both of the surface charge of CNTs and the dissociation degree of PA affected by solution pH, impacted the sorption process. In the dual-solute system, PA had competition and displacement effects on the sorption of DEP by CNTs. Under different pH conditions, the competition and displacement strength of PA to the sorption of DEP on CNTs was related to the dispersion stability of CNTs and the degree of dissociation of PA. Analysis based on site energy distribution showed that the number of available low-energy sorption sites increased although the addition of PA caused a significant decrease in the number of available high-energy sorption sites for DEP on CNTs.