Sorption of Polybrominated Diphenyl Ethers in Biosolid Model Samples

Abstract

Biosolid model samples (BMSs) were developed to study the capacity of various matrixes to adsorb polybrominated diphenyl ethers (PBDEs) as a function of their composition. A commercial standard reference samples for biosolids containing a certified amount of PBDEs is currently not available for extraction evaluation. Therefore, this study will allow for the selection of an appropriate concentration of PBDEs to produce a reference material for analytes associated with the matrix.The sorption of PBDEs increased clearly concomitantly with the amount of organic matter present in the model, revealing that organic matter rather than the inorganic fraction is mainly responsible for the analyte-matrix interaction. Hydrophobic interactions are predominant in the retention of PBDEs in the biosolid matrix because more hydrophobic congeners are generally sorbed to a higher extent than those that are less hydrophobic.In order to know the probable PBDE sorption mechanism on the model sample of biosolid, the Gibbs free energies were calculated using the Freundlich model, giving values between -8 and -10 kJ/mol. These results suggest that the sorption mechanism of the PBDEs is through physiosorption. Therefore, the Freundlich model should be satisfactory for describing the analyte behavior.

Sorption of Apolar Pesticides by Units of Benzoic Acid Propyl Ester in Cyclic Phosphazene

“…Consequently, a solvent mixture containing acetonitrile and calcium chloride 0.01 mol L -1 in a 60:40 ratio was selected to keep the pesticides dissolved after equilibrium and to maintain the ionic strength 55 . Despite the percentage of acetonitrile is impractical; the constructed isotherm was useful for estimating the amount of pesticides adsorbed by the matrix.…”