Effects of Copper on the Sorption of Phthalate Esters to Yellow River Sediment

Abstract

The sorption of hydrophobic organic pollutants on soils or sediments has been widely studied. However, more attention in the previous studies has been paid to sorption mechanism and effects of relevant environmental factors, few studies were reported on effects of heavy metals on the sorption of hydrophobic organic pollutants. In this paper, sorption of phthalate esters (diethyl phthalate, DEP, and di-n-butyl phthalate, DnBP) and copper on the Yellow River sediment was investigated with particular attention to the effects of copper on the phthalate sorption. The experimental results show that the sorption isotherms of phthalates could be reasonably described by the Freundlich equation. Higher sorption equilibrium constant was obtained for DnBP due to its greater hydrophobicity. The existence of copper would enhance the sorption of DnBP. Moreover, strong sorption of copper to sediment were found and attributed to abundant carbonates in the Yellow River sediment. After carbonates were removed, notable effects of copper on the phthalate sorption were observed due to the decrease of copper sorption and the increase of aqueous copper concentration.With 153 mg l −1 copper added, the partition coefficient decreases by 52% for DEP and increases by 79% for DnBP. Primary factors that may influence interaction between the sorption of copper and DEP and DnBP were also investigated, such as complexation between copper and phthalate, and phthalate hydrophobicity. The complexation between phthalate esters and copper was substantiated by polarogram and fluorescence spectrograph, and the calculated mol ratio of complexation (copper : phthalate) was found to be 2:1.

Occurrence of phthalate esters in river sediments in areas with different land use patterns

“…5A and B). Because PAEs are hydrophobic contaminants and readily adsorbed and fixed by sediment OM, local source transport and mixing processes are factors (Xu et al, 2007;Zeng et al, 2008;Liu et al, 2010;Magdouli et al, 2013;Zheng et al, 2014). In addition, no correlation was found between the Σ 6 PAEs and pH of the sediments (Fig.…”

“…Several studies have focused on the concentrations and distribution of PAEs in lakes and large rivers, but studies on suburban river networks are limited (Yuan et al, 2002;Xu et al, 2007;Sun et al, 2013;Zheng et al, 2014). Zeng et al (2008) reported that the Σ 16 PAEs concentrations in urban lake sediments ranged from 2.3 to 74.9 mg kg −1 dry weight (dw) with a mean concentration of 20.8 mg kg −1 in Guangzhou, South China.…”

Combined effect of co-existing heavy metals and organophosphate pesticide on adsorption of atrazine to river sediments

“…The surfacial sediments (SSs) and natural surface coating samples (NSCSs) are often considered as main carriers and potential sources of both organic and inorganic pollutants in aquatic environments [12][13][14]. They are playing a significant role in the adsorption of pollutants owing to their abundant internal surface area and high sorption intensity [15,16].…”

Contributions of Non-Residual (Fe Oxides, Mn Oxides and Organic Materials) and Residuals in Surficial Sediments to Atrazine Adsorption Using Artificial Neural Network Model

“…Mn oxides, Fe oxides and organic materials (OMs) are most important components in SSs [11,12]. They play important roles in controlling the adsorption of organic and inorganic contaminants, with different contribution to the adsorption [13][14][15]. The various sediment components may contribute independently to the sorption of organic pollutants; however, interactions between components may also take place [16].…”