The impact of water-soluble humic acids on extraction-photometric determination of anionic SAS with methylene blue in natural waters

Optimizing linear alkyl benzene sulfonate removal using Fenton oxidation process in Taguchi Method

“…Synthetic solutions were prepared by LAS ("Acros Organic", USA), C 18 H 29 NaO 3 S. Sampling and testing procedures were accomplished using the standard methods for the examination of water and wastewater. LAS was examined using 5540 C standard method [23,24] in which methylene blue active substances (MBAS) bring about the transfer of methylene blue, a cationic dye, from an aqueous solution into an immiscible organic liquid upon equilibration. The intensity of the resulting blue color in the organic phase is a measure of MBAS.…”

Evaluation of Efficacy of Anionic Surfactant Degradation in the Presence of Concomitant Impurities of Natural Waters

“…Change in ABS concentration during oxidation was monitored by standard extraction-photometric method with methylene blue (EPh) or advanced sorption-photometric (SPh) technique with methylene blue (determination limit of 0.05 mg/dm 3 and 0.02 mg/dm 3 , resp.) [8,14]. The latter method allows to significantly improve the accuracy of the ASAS control in waters with high content of the NOM.…”

“…The major organic impurities in surface waters-humic and fulvic acids (HA and FA) can fix organic xenobiotics (e.g., pesticides, petroleum products, surfactants, etc.) through different mechanisms, through formation of strong chemical bonds (such as ionic, hydrogen, and covalent), charge transfer or weak interactions (such as van der Waals forces, ligand exchange, hydrophobic links) [8][9][10][11]; therefore, they may significantly affect the properties and behavior of xenobiotics in the processes of natural water or sewage treatment [12,13]. In particular, HA are able to bind anionic surfactants (ASAS) through hydrophobic interactions, significantly distorting their quantification by standard extractionphotometric method with methylene blue [8,14].…”

“…through different mechanisms, through formation of strong chemical bonds (such as ionic, hydrogen, and covalent), charge transfer or weak interactions (such as van der Waals forces, ligand exchange, hydrophobic links) [8][9][10][11]; therefore, they may significantly affect the properties and behavior of xenobiotics in the processes of natural water or sewage treatment [12,13]. In particular, HA are able to bind anionic surfactants (ASAS) through hydrophobic interactions, significantly distorting their quantification by standard extractionphotometric method with methylene blue [8,14]. The binding of surfactants with mentioned natural organic matter (NOM) depends on the structure of the substrate and NOM and a number of other factors (such as pH, ionic strength, and duration of exposure) [8,10,11].…”

“…In particular, HA are able to bind anionic surfactants (ASAS) through hydrophobic interactions, significantly distorting their quantification by standard extractionphotometric method with methylene blue [8,14]. The binding of surfactants with mentioned natural organic matter (NOM) depends on the structure of the substrate and NOM and a number of other factors (such as pH, ionic strength, and duration of exposure) [8,10,11]. It was shown that HA have a greater affinity for binding surfactants and other xenobiotics than less hydrophobic FA [8][9][10]13].…”