Competitive adsorption of phthalate esters on marine surface sediments: kinetic, thermodynamic, and environmental considerations.
In this study, the sorption behavior of six widely used phthalate esters (PEs) on marine sediments was investigated. The adsorption of PEs was fast and reached the equilibrium within 6 h. The forward and backward rate constants of all PEs on sediments were calculated. Several kinds of kinetic and thermodynamic models have been investigated; the pseudo-second-order model and the partition isotherm model were best fitted to the adsorption behavior of PEs. The rate-limiting step of sorption was controlled by the film diffusion mechanism. After treating sediments with H2O2, the partition coefficients of all PEs were significantly reduced and indicated that the amorphous organic carbon has a major role in adsorption process. The negative values of ΔH° and ΔG° for these compounds showed that the sorption process is exothermic and spontaneous. The adsorption capacities of all PEs were slightly influenced by increasing the salinity from 0 to 40 g L-1. These research findings have a prime importance on assessment of the fate and transport of PEs in seawater-sediment systems.
Department of Marine Chemistry, Faculty of Marine Science, Khorramshahr University of Marine Science and Technology, Khorramshahr, P.O. BOX 669, Iran.
Somaye
S
Mohammadian
Department of Marine Chemistry, Faculty of Marine Science, Khorramshahr University of Marine Science and Technology, Khorramshahr, P.O. BOX 669, Iran. Kamal.ghanemi@kmsu.ac.ir.
Kamal
K
Ghanemi
Department of Marine Chemistry, Faculty of Marine Science, Khorramshahr University of Marine Science and Technology, Khorramshahr, P.O. BOX 669, Iran.
Yadollah
Y
Nikpour
D000327:Adsorption; D004952:Esters; D019015:Geologic Sediments / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D007700:Kinetics; D008962:Models, Theoretical; D010795:Phthalic Acids / Q000032:analysis*; D054712:Salinity; D012623:Seawater / Q000737:chemistry*; D013816:Thermodynamics; D014874:Water Pollutants, Chemical / Q000032:analysis*
D004952:Esters; D010795:Phthalic Acids; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide
Competitive adsorption; Kinetic and thermodynamic models; Marine sediment; Phthalate esters; Rate constants
Environ Int. 2008 Apr;34(3):372-80
17915327
Environ Sci Technol. 2005 Apr 1;39(7):2033-41
15871234
Environ Sci Pollut Res Int. 2016 Aug;23 (15):15749-56
27146532
Mar Pollut Bull. 2013 Nov 15;76(1-2):220-6
24054732
Chemosphere. 2010 Sep;80(11):1321-7
20619874
Mar Pollut Bull. 2008;57(6-12):403-8
18304587
Springerplus. 2013 Aug 30;2:422
24024106