Joint influence of surfactants and humic matter on PAH solubility. Are mixed micelles formed?

Lippold, Holger; Gottschalch, U.; Kupsch, H.

doi:10.1016/j.chemosphere.2007.09.040

Cited by 52 publications

(37 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The significant increase of inhibition evidenced in the presence of soil confirms the results reported in previous studies (Fabbri et al 2008). This effect can be in part due to the fact that humic compounds can be themselves degraded (Minero et al 1999) and in part attributed to the joint influence of humic matter and surfactants on pollutants solubility (Lippold et al 2008), which can significantly modify the solute-micelle binding, altering the substrates partitioning in the heterogeneous system. The same general behaviour shown in Fig.…”

Section: Photocatalytic Treatment Of Soil Washing Extractsmentioning

confidence: 99%

Removal of alkylphenols from polluted sites using surfactant-assisted soil washing and photocatalysis

Davezza

Fabbri

Prevot

et al. 2010

Environ Sci Pollut Res

View full text Add to dashboard Cite

Background and Purpose Surfactant-assisted soil washing and photocatalysis are well known remediation processes of environmental concern. The application of photocatalysis to treat soil washing extracts containing 4-methylphenol, 4-ethylphenol and 4-tert-butylphenol in the presence of nonionic (C 12 E 8 and C 12 E 23 ) and anionic (SDS) surfactants and some of their binary mixtures was investigated in this work by studying the pollutants degradation in the presence of TiO 2 dispersions irradiated with simulated solar light. Materials and methods Clean soil samples were spiked with the investigated alkylphenols. Aqueous solutions of the chosen surfactants were placed in contact for some hours with the spiked soil samples in a rotatory mixer. The pollutants recoveries were evaluated via HPLC analysis. Photocatalytic experiments were performed in solarbox on aqueous solutions and on aqueous surfactant solutions containing the pollutants. Results The pollutants removal from the soil was proven effective using the examined surfactant solutions. The photocatalytic treatment of the wastes was faster using Brij 35, but also SDS and C 12 E 8 -SDS mixtures can be applied. After 2-5 hours the complete pollutants abatement was obtained, depending on the surfactant chosen and on the amount of TiO 2 employed. On the contrary, the treatment of wastes containing C 12 E 8 was an extremely slow process. Conclusions The photocatalytic approach can be applied to remove the examined aromatic pollutants from the washing wastes, confirming the viable coupling between this advanced oxidation method and the surfactant-based soil remediation treatments. Surfactant adsorption onto TiO 2 and micelles concentration play a dominant role.

show abstract

Section: Photocatalytic Treatment Of Soil Washing Extractsmentioning

confidence: 99%

Removal of alkylphenols from polluted sites using surfactant-assisted soil washing and photocatalysis

Davezza

Fabbri

Prevot

et al. 2010

Environ Sci Pollut Res

View full text Add to dashboard Cite

show abstract

“…Substances like anthropogenic and naturally occurring organic acids and surfactants are solubilizing agents present in dissolved organic matter. The dissolved organic matter takes part in the transport mechanism of PAHs [4].…”

Section: Introductionmentioning

confidence: 99%

Removal of Phenanthrene in an Aqueous Matrix by Entrapped Crude Enzymes on Alginate Beads Combined with TiO2-C-Ag Coated Fiberglass

González-Ramírez¹,

Ávila-Pérez²,

Torres-Bustillos³

et al. 2017

IJESD

View full text Add to dashboard Cite

Abstract-The polycyclic aromatic hydrocarbons (PAHs) are classified as a public health hazard, and priority pollutants to be eliminated from water. The degradation of PAHs is abetted by its low water solubility, yet countered by its attached to organic matter complicating the PAHs' removal from wastewater. In this study, the use of two different types of mechanisms to overcome the drawbacks of the presence of dissolved organic matter was evaluated in PHE (phenanthrene) removal. The combination of crude enzymes entrapped in alginate gels with heterogeneous photocatalysis adds the catalytic activity of the enzymes to PHE treatment without requiring special conditions. The application of photocatalysis techniques for water recuperation is subject to photon incidence over the catalyst, which affects the efficiency of the process. The combined system removed 94.3 ± 2.0% of PHE in the presence of polyoxyethylene sorbitan monooleate and dimethyl sulfoxide. The alginate gels were able to maintain the catalytic activity of the enzymes, while the TiO 2 -C-Ag was activated under low-energy UV light (365-465 nm) with the Ag islands acting as electron donors. The latter was confirmed in the surface analysis by X-ray photoelectron spectroscopy, which presented an increase in carbonyl groups in both materials and a change from Ag 0 to Ag 3+ after 13 h of treatment. The combination of both treatments improved removal in a single TiO 2 -C-Ag treatment.

show abstract

“…For mixtures of surfactants, competitive, synergistic as well as neutral effects on HOC transport have been reported, mainly reflected by changes to CMC values following formation of mixed micelles (Zhou and Zhu, 2004;Mohamed and Mahfoodh, 2006) and altered surfactant sorption to soil (Yang et al, 2005;Tripathi and Brown, 2008). There is also some evidence that surfactants interact with soil colloids (HAs, DOM) to form mixed micelles, which may enhance the transport of SHOCs (Cheng and Wong, 2006), although a similar result was not found in later studies with different surfactants and colloids (Lippold et al, 2008). Synergistic behaviour has also been reported as a result of mixed micellisation of synthetic and bio-surfactants (Rao and Paria, 2009).…”

Section: Processes and Factors Driving Ft Of Shocs In Soilsmentioning

confidence: 69%

“…Few studies, however, have investigated the interactions between HAs and surfactants (either individually or as surfactant mixtures) or their combined solubilising capacity for contaminants and where available, the results are not conclusive as to whether interactions are occurring or not (Otto et al, 2003;Koopal et al, 2004;Lippold et al, 2008). The impact of surfactant-HA mixtures on SHOC partitioning, and hence their facilitated transport potential, is unknown.…”

Section: Shoc Partitioning To Surfactant Mixed Micelles At Different mentioning

confidence: 99%

“…Their solubility behaviour distinguishes HAs from humins (insoluble) and fulvic acids (soluble at all pH). Due to their aqueous solubility, HAs as well as surfactants can easily be transported in the aqueous phase through soil and together they may play an important role in the solubilisation and distribution of HOCs in such environments (Chiou et al, 1979;Chiou et al, 1986;Weber et al, 1992;Huang, 1997;Kilduff and Wigton, 1999;de Jonge et al, 2004;McCarthy and McKay, 2004;Cheng and Wong, 2006;Lippold et al, 2008;ter Laak et al, 2009;Grant et al, 2011b).…”

Section: Shoc Partitioning To Surfactant Mixed Micelles At Different mentioning

confidence: 99%

See 1 more Smart Citation

Processes governing facilitated transport of super-hydrophobic organic contaminants

Schacht¹

View full text Add to dashboard Cite

Super-hydrophobic organic contaminants (SHOCs, log KOW>6) have extremely poor water solubility and a relative high affinity for organic matter. Representatives of this group, such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated biphenyls (PCBs), brominated flame retardants, and various pesticides, are hazardous to the environment and human health. Due to their physico-chemical properties, SHOCs are generally considered immobile in the subsurface. However, their vertical transport in soil can be facilitated by mobile species such as surfactants and humic acids (HAs), (on)to which SHOCs can sorb.Via such facilitators, SHOCs can be solubilised in water and transported through the soil column, causing unexpected groundwater contamination or offsite transport. Although facilitated transport (FT) is a recognised mechanism, its extent and significance in the environment remains poorly understood, and available information is inadequate to assess, and if necessary, manage risks associated with FT. The SHOC mobility under FT is largely driven by their partitioning behaviour between soil, water and mixture of dissolved facilitators. These processes are difficult to quantify for SHOCs, due to experimental challenges associated with measuring concentrations of highly hydrophobic compounds in dissolved phases. Therefore, the aim of this PhD project was to develop and validate reliable methods to experimentally determine equilibrium SHOC partition constants for facilitators in aqueous solutions, and also quantify SHOC partitioning to mixed facilitator systems.A novel method to determine partition constants for contaminants between water and dissolved phases involves dosing polymers (e.g. polydimethylsiloxane, PDMS) as a third phase using a mass balance approach. However, this methodology requires reliable PDMSwater partition constants (KPDMSw), which are scarce for SHOCs. Chapter 2 introduces a new, rapid and robust method to estimate KPDMSw data and activity coefficients in PDMS. In Chapter 3, the passive dosing approach was adapted and validated for SHOCs in order to measure water-dissolved phase partition constants. Precisely loaded SHOC masses in the PDMS are a key requirement for robust data, which was achieved by refining a swellingbased polymer loading technique introduced (Chapter 2). Optimising the experimental system significantly reduced equilibration times, and the modified approach was applied to derive partition constants of PCBs and PCDDs between water and the monomers (KMO) and micelles (KMI) of a model surfactant (sodium dodecyl sulfate). Log KMI data ranged from 5.2 to 7.0 for PCDDs and 6.6 to 7.5 for PCBs, and showed a linear relationship with hydrophobicity, consistent with trends derived from previous data for moderately hydrophobic compounds. The apparent solubility enhancement factors, derived from these partition constants, were highest with micelles. However, the results also indicated that considerable apparent solubility enhancement can occur in monomer-containing solutions. In...

show abstract

Joint influence of surfactants and humic matter on PAH solubility. Are mixed micelles formed?

Cited by 52 publications

References 72 publications

Removal of alkylphenols from polluted sites using surfactant-assisted soil washing and photocatalysis

Removal of alkylphenols from polluted sites using surfactant-assisted soil washing and photocatalysis

Removal of Phenanthrene in an Aqueous Matrix by Entrapped Crude Enzymes on Alginate Beads Combined with TiO2-C-Ag Coated Fiberglass

Processes governing facilitated transport of super-hydrophobic organic contaminants

Contact Info

Product

Resources

About