Concentration Distribution and Ecological Risk Assessment of Polycyclic Aroma...Scientific Review SR
The ecological risk assessment of 16 USEPA priority polycyclic aromatic hydrocarbon (PAHs) in water and sediments of Kolo creek, Niger Delta Nigeria was assessed the samples were collected from November, 2018 to June, 2019 from seven locations (A-G) along the creek. The samples were extracted using standard methods and analyzed using gas chromatography (model: HP5890 S). The concentrations of the PAHs in the water and sediment samples ranged between 0.000 - 9.239 µ/L and .002 – 374.35µg/Kg respectively. All the compounds analyzed were detected in all the sampling places, even area far from the flow stations. Hence, the urban runoffs, sewage discharges, and agricultural activities are implicated. Four rings hydrocarbon were present in higher concentration when compared to other PAHs in all sampling sites, with benz (a)anthracene having the highest values in both matrixes. Similarly, lower molecular weight (LMW) PAHs were present in lower concentrations in all sampling sites and they are known to exhibit higher lethal toxicity than the larger PAHs. HMW were present in high concentrations than LMW and are persistent in the environment as a result of their increase resistance to oxidation, reduction and vaporization as molecular weight increases. Similarly, The PAFs of the investigated creek is less than 5%, suggesting existences of minor ecological risks that are insignificance. However, the TEQs detected in high molecular weight showed that there is possibility of cancer to those who may be exposed to the bottom sediment. The indices measured in this habitat may put more pressures to the aquatic organisms and cause drastic changes to their ecosystem which may lead to species extinction.
The demand for efficient and cost effective wastewater treatment technology in the refining and petrochemical sector is being driven by not only ever-tightening environmental legislation, but also by the sectors own desire to follow a meaningful sustainability agenda and to take its responsibilities around product stewardship seriously.
Treatment of wastewater from petrochemical plants can be a challenging and costly matter; particularly when needing to comply with the requirements of operational permits and national environmental legislation governing the discharge of treated wastewater into community treatment plants or natural water bodies such as rivers, lakes and oceans.
Chemosphere 72 (2008) 1588–1593Contents lists available at S.docxchristinemaritza
Chemosphere 72 (2008) 1588–1593
Contents lists available at ScienceDirect
Chemosphere
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / c h e m o s p h e r e
Removal of perfluorinated surfactants by sorption onto granular activated
carbon, zeolite and sludge
Valeria Ochoa-Herrera, Reyes Sierra-Alvarez *
Department of Chemical and Environmental Engineering, University of Arizona, Tucson, AZ 85721-0011, USA
a r t i c l e i n f o a b s t r a c t
Article history:
Received 4 January 2008
Received in revised form 9 April 2008
Accepted 9 April 2008
Available online 3 June 2008
Keywords:
Adsorption
Biosorption
PFC
PFOS
PFOA
PFBS
0045-6535/$ - see front matter � 2008 Elsevier Ltd. A
doi:10.1016/j.chemosphere.2008.04.029
* Corresponding author. Tel.: +1 520 626 2896; fax
E-mail address: [email protected] (R. Sierr
Perfluorinated surfactants are emerging pollutants of increasing public health and environmental
concern due to recent reports of their world-wide distribution, environmental persistence and bioaccu-
mulation potential. Treatment methods for the removal of anionic perfluorochemical (PFC) surfactants
from industrial effluents are needed to minimize the environmental release of these pollutants. Removal
of PFC surfactants from aqueous solutions by sorption onto various types of granular activated carbon
was investigated. Three anionic PFC surfactants, i.e., perfluorooctane sulfonate (PFOS), perfluorooctanoic
acid (PFOA) and perfluorobutane sulfonate (PFBS), were evaluated for the ability to adsorb onto activated
carbon. Additionally, the sorptive capacity of zeolites and sludge for PFOS was compared to that of
granular activated carbon. Adsorption isotherms were determined at constant ionic strength in a pH
7.2 phosphate buffer at 30 �C. Sorption of PFOS onto activated carbon was stronger than PFOA and PFBS,
suggesting that the length of the fluorocarbon chain and the nature of the functional group influenced
sorption of the anionic surfactants. Among all adsorbents evaluated in this study, activated carbon
(Freundlich KF values = 36.7�60.9) showed the highest affinity for PFOS at low aqueous equilibrium
concentrations, followed by the hydrophobic, high-silica zeolite NaY (Si/Al 80, KF = 31.8), and anaerobic
sludge (KF = 0.95�1.85). Activated carbon also displayed a superior sorptive capacity at high soluble
concentrations of the surfactant (up to 80 mg l�1). These findings indicate that activated carbon adsorp-
tion is a promising treatment technique for the removal of PFOS from dilute aqueous streams.
� 2008 Elsevier Ltd. All rights reserved.
1. Introduction
Perfluorinated (PFC) surfactants are emerging pollutants that
have been used for the last 50 years in a wide variety of industrial
processes and consumer-based products, including polymer addi-
tives, lubricants, fire retardants and suppressants, pesticides, and
surfactants (Kissa, 2001). Quantitatively, pefluorooctane sulfonate
(PFOS, C8F17SO3H) and ...
Concentration Distribution and Ecological Risk Assessment of Polycyclic Aroma...Scientific Review SR
The ecological risk assessment of 16 USEPA priority polycyclic aromatic hydrocarbon (PAHs) in water and sediments of Kolo creek, Niger Delta Nigeria was assessed the samples were collected from November, 2018 to June, 2019 from seven locations (A-G) along the creek. The samples were extracted using standard methods and analyzed using gas chromatography (model: HP5890 S). The concentrations of the PAHs in the water and sediment samples ranged between 0.000 - 9.239 µ/L and .002 – 374.35µg/Kg respectively. All the compounds analyzed were detected in all the sampling places, even area far from the flow stations. Hence, the urban runoffs, sewage discharges, and agricultural activities are implicated. Four rings hydrocarbon were present in higher concentration when compared to other PAHs in all sampling sites, with benz (a)anthracene having the highest values in both matrixes. Similarly, lower molecular weight (LMW) PAHs were present in lower concentrations in all sampling sites and they are known to exhibit higher lethal toxicity than the larger PAHs. HMW were present in high concentrations than LMW and are persistent in the environment as a result of their increase resistance to oxidation, reduction and vaporization as molecular weight increases. Similarly, The PAFs of the investigated creek is less than 5%, suggesting existences of minor ecological risks that are insignificance. However, the TEQs detected in high molecular weight showed that there is possibility of cancer to those who may be exposed to the bottom sediment. The indices measured in this habitat may put more pressures to the aquatic organisms and cause drastic changes to their ecosystem which may lead to species extinction.
The demand for efficient and cost effective wastewater treatment technology in the refining and petrochemical sector is being driven by not only ever-tightening environmental legislation, but also by the sectors own desire to follow a meaningful sustainability agenda and to take its responsibilities around product stewardship seriously.
Treatment of wastewater from petrochemical plants can be a challenging and costly matter; particularly when needing to comply with the requirements of operational permits and national environmental legislation governing the discharge of treated wastewater into community treatment plants or natural water bodies such as rivers, lakes and oceans.
Chemosphere 72 (2008) 1588–1593Contents lists available at S.docxchristinemaritza
Chemosphere 72 (2008) 1588–1593
Contents lists available at ScienceDirect
Chemosphere
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / c h e m o s p h e r e
Removal of perfluorinated surfactants by sorption onto granular activated
carbon, zeolite and sludge
Valeria Ochoa-Herrera, Reyes Sierra-Alvarez *
Department of Chemical and Environmental Engineering, University of Arizona, Tucson, AZ 85721-0011, USA
a r t i c l e i n f o a b s t r a c t
Article history:
Received 4 January 2008
Received in revised form 9 April 2008
Accepted 9 April 2008
Available online 3 June 2008
Keywords:
Adsorption
Biosorption
PFC
PFOS
PFOA
PFBS
0045-6535/$ - see front matter � 2008 Elsevier Ltd. A
doi:10.1016/j.chemosphere.2008.04.029
* Corresponding author. Tel.: +1 520 626 2896; fax
E-mail address: [email protected] (R. Sierr
Perfluorinated surfactants are emerging pollutants of increasing public health and environmental
concern due to recent reports of their world-wide distribution, environmental persistence and bioaccu-
mulation potential. Treatment methods for the removal of anionic perfluorochemical (PFC) surfactants
from industrial effluents are needed to minimize the environmental release of these pollutants. Removal
of PFC surfactants from aqueous solutions by sorption onto various types of granular activated carbon
was investigated. Three anionic PFC surfactants, i.e., perfluorooctane sulfonate (PFOS), perfluorooctanoic
acid (PFOA) and perfluorobutane sulfonate (PFBS), were evaluated for the ability to adsorb onto activated
carbon. Additionally, the sorptive capacity of zeolites and sludge for PFOS was compared to that of
granular activated carbon. Adsorption isotherms were determined at constant ionic strength in a pH
7.2 phosphate buffer at 30 �C. Sorption of PFOS onto activated carbon was stronger than PFOA and PFBS,
suggesting that the length of the fluorocarbon chain and the nature of the functional group influenced
sorption of the anionic surfactants. Among all adsorbents evaluated in this study, activated carbon
(Freundlich KF values = 36.7�60.9) showed the highest affinity for PFOS at low aqueous equilibrium
concentrations, followed by the hydrophobic, high-silica zeolite NaY (Si/Al 80, KF = 31.8), and anaerobic
sludge (KF = 0.95�1.85). Activated carbon also displayed a superior sorptive capacity at high soluble
concentrations of the surfactant (up to 80 mg l�1). These findings indicate that activated carbon adsorp-
tion is a promising treatment technique for the removal of PFOS from dilute aqueous streams.
� 2008 Elsevier Ltd. All rights reserved.
1. Introduction
Perfluorinated (PFC) surfactants are emerging pollutants that
have been used for the last 50 years in a wide variety of industrial
processes and consumer-based products, including polymer addi-
tives, lubricants, fire retardants and suppressants, pesticides, and
surfactants (Kissa, 2001). Quantitatively, pefluorooctane sulfonate
(PFOS, C8F17SO3H) and ...
With 30 years of experience across the food science and packaging spectrum, Dr Claire Sand through her company, Packaging Technology & Research, offers clients solutions using Strategy, Technology, Consulting and Coaching.
Want to know more about how this article affect your business? Reach out to Dr Sand on Linked In - https://www.linkedin.com/in/clairekoelschsand
Want to keep learning from Dr. Sand? View more of her presentations and articles at https://www.packagingtechnologyandresearch.com/expertise.html
Dr. Claire Sand | Owner, Packaging Technology & Research, LLC; Adjunct Professor, Michigan State University; Columnist for Food Technology Magazine
http://www.packagingtechnologyandresearch.com/
OECD Global Forum on the Environment dedicated to Per- and Polyfluoroalkyl Su...OECD Environment
PFAS, which stands for per- and polyfluoroalkyl substances, are a diverse group of chemicals that include PFCAs, PFOA, PFSAs, PFHxS, and thousands of others. These chemicals have been in commercial production since the 1950s and are now widely used in consumer and industrial applications. One characteristic of PFAS is their persistence in the environment, as they are extremely resistant to degradation. PFAS have emerged as contaminants of global concern because of their potential to accumulate in the human body and food chains.
On 12-13 February 2024, a wide range of stakeholders, including governments, industry, non-governmental organisations (NGOs), and academics came together to discuss various topics related to PFAS. These topics covered areas such as country risk management approaches, innovation challenges for finding safer alternatives, effective risk communication strategies, monitoring techniques, waste management, and approaches to managing contamination.
This presentation summarizes the ongoing Canada-wide SWM pond sediment chemistry study, which Francine Kelly-Hooper began in 2005. The results demonstrate that most sediments would require regulated waste management due to exceedences of the Ontario Regulation 153/04 soil standards. Non-hazardous landfill disposal is currently the most common practice, which is extremely expensive and environmentally unsustainable. However, the chemistry data also demonstrates that the sediments would meet Ontario biosolids guidelines and Ontario Nutrient Management Act land application requirements if matched to the appropriate recipient site. This is the premise for the Canadian Food Inspection Agency's first approval of a field pilot study that will use SWM pond sediment as topsoil amendment materials on tree nursery soils.
This presentation is all about the systemic administration of fluorides ,as it is an easier way for the administration of fluorides to prevent dental caries and tooth decay.the aim is to explain the advantages of systemic fluoride ,their present status in India and in other countries and to create awareness among population.Also raising an issue that how these methods of systemic fluoride administration can be improved so that there is better prevention of decay problems
This presentation discusses the measurement of PFCs in drinking and tap water using LC-MS/MS. As contaminants of emerging concern, research on PFCs is ongoing to determine the impacts of these materials on human health and the environment. Perfluorinated compounds can be effectively and quickly measured directly from surface and drinking water using a modified configuration of the LCMS-8050. For more information, go to ssi.shimadzu.com and follow Shimadzu on Twitter @ShimadzuSSI. Thanks for viewing.
OECD Global Forum on the Environment dedicated to Per- and Polyfluoroalkyl Su...OECD Environment
PFAS, which stands for per- and polyfluoroalkyl substances, are a diverse group of chemicals that include PFCAs, PFOA, PFSAs, PFHxS, and thousands of others. These chemicals have been in commercial production since the 1950s and are now widely used in consumer and industrial applications. One characteristic of PFAS is their persistence in the environment, as they are extremely resistant to degradation. PFAS have emerged as contaminants of global concern because of their potential to accumulate in the human body and food chains.
On 12-13 February 2024, a wide range of stakeholders, including governments, industry, non-governmental organisations (NGOs), and academics came together to discuss various topics related to PFAS. These topics covered areas such as country risk management approaches, innovation challenges for finding safer alternatives, effective risk communication strategies, monitoring techniques, waste management, and approaches to managing contamination.
Study and prediction of persistent organochlorine and organophosphorous pesti...iosrjce
The indiscriminate use of toxic pesticides had created an environment that without this poison the
plant life is unfruitful leading to the farmer’s life miserable. For several years, this phenomenon was continuing
and the ecosystem is protecting the environment and the life of human being from high risk of toxicity. But, how
long it will continue or weather a paradigm change in the agricultural field is required? With this objective a
field study was conducted in the cardamom plantations of Idukki district in South India to estimate and predict
the persistence of pesticide residue in the soil environment. It is observed that residues of endosulfan, DDT and
organophosphorous pesticides were present in soil samples at 31.6 %, 29 % and 21 % respectively. The present
study gives a prediction of the concentration of persistent pesticide residues in the soil if the present dose and
frequency of application is continued. The study also highlighted the adsorption capacity of soil in the study
area and low water solubility of pesticides used in cardamom plantations which is referred as partition
coefficient. The soil properties such as pH, organic content and microbial concentration which determine the
fate of degradation of pesticides and formation of its metabolites are also been discussed in this context. Based
on the observations and analysis, it is concluded that the formation of degradation products and bound residues
decrease at higher concentration of pesticide applications but the concentration of persistent pesticides
increases and the biodegradation reduced in such cases due to bound residues and reduced biological activity.
The predicted values on multiple applications where the concentrations in soil may build up and reach a
plateau, are 2.559,0.2559, 1.7324 and 0.659 mgKg-1
in the case of endosulfan, DDT, organophosphorous and
total pesticides respectively.
OECD Global Forum on the Environment dedicated to Per- and Polyfluoroalkyl Su...OECD Environment
PFAS, which stands for per- and polyfluoroalkyl substances, are a diverse group of chemicals that include PFCAs, PFOA, PFSAs, PFHxS, and thousands of others. These chemicals have been in commercial production since the 1950s and are now widely used in consumer and industrial applications. One characteristic of PFAS is their persistence in the environment, as they are extremely resistant to degradation. PFAS have emerged as contaminants of global concern because of their potential to accumulate in the human body and food chains.
On 12-13 February 2024, a wide range of stakeholders, including governments, industry, non-governmental organisations (NGOs), and academics came together to discuss various topics related to PFAS. These topics covered areas such as country risk management approaches, innovation challenges for finding safer alternatives, effective risk communication strategies, monitoring techniques, waste management, and approaches to managing contamination.
Two case studies are presented on the beneficial use of SWM pond sediments as environmentally sustainable and cost effective alternatives to landfill disposal.
With 30 years of experience across the food science and packaging spectrum, Dr Claire Sand through her company, Packaging Technology & Research, offers clients solutions using Strategy, Technology, Consulting and Coaching.
Want to know more about how this article affect your business? Reach out to Dr Sand on Linked In - https://www.linkedin.com/in/clairekoelschsand
Want to keep learning from Dr. Sand? View more of her presentations and articles at https://www.packagingtechnologyandresearch.com/expertise.html
Dr. Claire Sand | Owner, Packaging Technology & Research, LLC; Adjunct Professor, Michigan State University; Columnist for Food Technology Magazine
http://www.packagingtechnologyandresearch.com/
OECD Global Forum on the Environment dedicated to Per- and Polyfluoroalkyl Su...OECD Environment
PFAS, which stands for per- and polyfluoroalkyl substances, are a diverse group of chemicals that include PFCAs, PFOA, PFSAs, PFHxS, and thousands of others. These chemicals have been in commercial production since the 1950s and are now widely used in consumer and industrial applications. One characteristic of PFAS is their persistence in the environment, as they are extremely resistant to degradation. PFAS have emerged as contaminants of global concern because of their potential to accumulate in the human body and food chains.
On 12-13 February 2024, a wide range of stakeholders, including governments, industry, non-governmental organisations (NGOs), and academics came together to discuss various topics related to PFAS. These topics covered areas such as country risk management approaches, innovation challenges for finding safer alternatives, effective risk communication strategies, monitoring techniques, waste management, and approaches to managing contamination.
This presentation summarizes the ongoing Canada-wide SWM pond sediment chemistry study, which Francine Kelly-Hooper began in 2005. The results demonstrate that most sediments would require regulated waste management due to exceedences of the Ontario Regulation 153/04 soil standards. Non-hazardous landfill disposal is currently the most common practice, which is extremely expensive and environmentally unsustainable. However, the chemistry data also demonstrates that the sediments would meet Ontario biosolids guidelines and Ontario Nutrient Management Act land application requirements if matched to the appropriate recipient site. This is the premise for the Canadian Food Inspection Agency's first approval of a field pilot study that will use SWM pond sediment as topsoil amendment materials on tree nursery soils.
This presentation is all about the systemic administration of fluorides ,as it is an easier way for the administration of fluorides to prevent dental caries and tooth decay.the aim is to explain the advantages of systemic fluoride ,their present status in India and in other countries and to create awareness among population.Also raising an issue that how these methods of systemic fluoride administration can be improved so that there is better prevention of decay problems
This presentation discusses the measurement of PFCs in drinking and tap water using LC-MS/MS. As contaminants of emerging concern, research on PFCs is ongoing to determine the impacts of these materials on human health and the environment. Perfluorinated compounds can be effectively and quickly measured directly from surface and drinking water using a modified configuration of the LCMS-8050. For more information, go to ssi.shimadzu.com and follow Shimadzu on Twitter @ShimadzuSSI. Thanks for viewing.
OECD Global Forum on the Environment dedicated to Per- and Polyfluoroalkyl Su...OECD Environment
PFAS, which stands for per- and polyfluoroalkyl substances, are a diverse group of chemicals that include PFCAs, PFOA, PFSAs, PFHxS, and thousands of others. These chemicals have been in commercial production since the 1950s and are now widely used in consumer and industrial applications. One characteristic of PFAS is their persistence in the environment, as they are extremely resistant to degradation. PFAS have emerged as contaminants of global concern because of their potential to accumulate in the human body and food chains.
On 12-13 February 2024, a wide range of stakeholders, including governments, industry, non-governmental organisations (NGOs), and academics came together to discuss various topics related to PFAS. These topics covered areas such as country risk management approaches, innovation challenges for finding safer alternatives, effective risk communication strategies, monitoring techniques, waste management, and approaches to managing contamination.
Study and prediction of persistent organochlorine and organophosphorous pesti...iosrjce
The indiscriminate use of toxic pesticides had created an environment that without this poison the
plant life is unfruitful leading to the farmer’s life miserable. For several years, this phenomenon was continuing
and the ecosystem is protecting the environment and the life of human being from high risk of toxicity. But, how
long it will continue or weather a paradigm change in the agricultural field is required? With this objective a
field study was conducted in the cardamom plantations of Idukki district in South India to estimate and predict
the persistence of pesticide residue in the soil environment. It is observed that residues of endosulfan, DDT and
organophosphorous pesticides were present in soil samples at 31.6 %, 29 % and 21 % respectively. The present
study gives a prediction of the concentration of persistent pesticide residues in the soil if the present dose and
frequency of application is continued. The study also highlighted the adsorption capacity of soil in the study
area and low water solubility of pesticides used in cardamom plantations which is referred as partition
coefficient. The soil properties such as pH, organic content and microbial concentration which determine the
fate of degradation of pesticides and formation of its metabolites are also been discussed in this context. Based
on the observations and analysis, it is concluded that the formation of degradation products and bound residues
decrease at higher concentration of pesticide applications but the concentration of persistent pesticides
increases and the biodegradation reduced in such cases due to bound residues and reduced biological activity.
The predicted values on multiple applications where the concentrations in soil may build up and reach a
plateau, are 2.559,0.2559, 1.7324 and 0.659 mgKg-1
in the case of endosulfan, DDT, organophosphorous and
total pesticides respectively.
OECD Global Forum on the Environment dedicated to Per- and Polyfluoroalkyl Su...OECD Environment
PFAS, which stands for per- and polyfluoroalkyl substances, are a diverse group of chemicals that include PFCAs, PFOA, PFSAs, PFHxS, and thousands of others. These chemicals have been in commercial production since the 1950s and are now widely used in consumer and industrial applications. One characteristic of PFAS is their persistence in the environment, as they are extremely resistant to degradation. PFAS have emerged as contaminants of global concern because of their potential to accumulate in the human body and food chains.
On 12-13 February 2024, a wide range of stakeholders, including governments, industry, non-governmental organisations (NGOs), and academics came together to discuss various topics related to PFAS. These topics covered areas such as country risk management approaches, innovation challenges for finding safer alternatives, effective risk communication strategies, monitoring techniques, waste management, and approaches to managing contamination.
Two case studies are presented on the beneficial use of SWM pond sediments as environmentally sustainable and cost effective alternatives to landfill disposal.
1. Coagulant-Enhanced Sorption of Perfluoroalkyl Substances
Yousof Aly1, Daniel P. McInnis1, Chen Liu2, Bonnie A. Lyon2, Kurt D. Pennell2, William A. Arnold3, Matt F. Simcik1
1University of Minnesota – School of Public Health; 2Tufts University – Department of Civil and Environmental Engineering; 3University of Minnesota – Department of Civil, Environmental, and Geo- Engineering
1. BACKGROUND 4. RESULTS
• Simple coagulants alum [Al2(SO4)3] and ferric chloride
[FeCl3∙6H2O] could remove PFOA, PFOS from solution
• Removal efficiencies ranged from 0-35% depending on
solution pH and coagulant dose
3. MATERIALS AND METHODS
polydiallyldimethyl
ammonium chloride
(polyDADMAC)
epichlorohydrin-
dimethylamine
(polyamine) 5. CONCLUSIONS
• Greater sorption of PFASs in the presence of cationic coagulant
• polyDADMAC significantly better than polyamine and poly aluminum chloride
• % increase in Kd for Poly-DADMAC = 66-378%
• % PFAS removal with addition of sorption enhancer = 0-25%
Perfluoroalkyl substances (PFASs)
PFBS perfluorobutane sulfonate
PFHxS perfluorohexane sulfonate
PFOS perfluorooctane sulfonate
PFHpA perfluoroheptanoic acid
PFOA perfluorooctanoic acid
PFNA perfluorononanoic acid
+
6. FUTURE DIRECTIONS
•Sorption of PFAS on contaminated soil (Tinker Air Force Base, Oklahoma, USA)
•Controlled release of coagulant
•Effectiveness of coagulants in the presence of co-contaminants (diesel fuel)
•One-dimensional column studies and two-dimensional aquifer cells
AlnCl(3n-m)(OH)m
Johnson, R.L., Anschutz, A.J., Smolen, J.M., Simcik, M.F., Penn, R.L., 2007. The
adsorption of perfluorooctanesulfonate onto sand, clay, and iron oxide surfaces. J.
Chem. Eng. Data 52, 1165-1170.
Xiao, F., Simcik, M.F., Gulliver, J.S., 2013. Mechanisms for removal of perfluorooctane
sulfonate (PFOS) and perfluorooctanoate (PFOA) from drinking water by conventional
and enhanced coagulation. Water Res. 47, 49-56.
This material is based upon work supported by the U.S. Army Corps of Engineers,
Humphreys Engineer Center Support Activity under Contract No. W912HQ-14-C-0042.
polyaluminum
chloride
2. HYPOTHESIS AND PREDICTIONS
• Since PFAS exhibit negative charges in water, we hypothesize that cationic coagulants will enhance their sorption to
Ottawa sand
• Furthermore, Ottawa sand is less sorptive than natural soils, so we predict further enhanced sorption of PFAS on
aquifer materials
% increase in Kd
over control
polyDADMAC polyamine polyaluminum
chloride
PFBS 95% 12% -13%
PFHxS 73% 31% 52%
PFOS 105% 43% 7%
PFHpA 66% -29% -11%
PFOA 378% 100% 18%
PFNA 124% 65% 24%
7. REFERENCES AND ACKNOWLEDGEMENTS
• 25 g Ottawa Sand (40-60 mesh), 10 mL water, sorption enhancer (100 mg/L), and PFASs added simultaneously
• Batches placed on wrist shaker for 24 hours to reach equilibrium
• Sorption enhancer dose selected based on monolayer coverage determined from sorption enhancer isotherms (shown
above)
Xiao et al. (2013)Johnson et al. (2007)
• Sorption of PFOS to Ottawa sand higher than would be
predicted from organic carbon content alone
• 74 – 99% of PFOS could be adsorbed onto solid surfaces
in a groundwater system
Sorption Enhancers
→
Analysis:
• PFASs analyzed by LC/MS following method described by Xiao et al. 2013.
• Labeled isotopes used as internal standards for quantification.
PFASAdsorbed(ng/gsand)
Equilibrium PFAS Concentration (ng/mL)
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0 20 40 60 80 100
PFBS
control
polyaluminum chloride
polyamine
polyDADMAC
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0 20 40 60 80 100
PFHxS
-0.5
1.5
3.5
5.5
7.5
9.5
11.5
0 20 40 60 80 100
PFOS
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0 20 40 60 80 100
PFHpA
-0.5
0.5
1.5
2.5
3.5
4.5
5.5
6.5
7.5
0 20 40 60 80 100
PFOA
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0 20 40 60 80 100
PFNA
0
0.2
0.4
0.6
0.8
1
1.2
0.0 50.0 100.0 150.0
*polyaluminum chloride
equilibrium enhancer concentration mg/L
* concentration in mg Al/L
mgenhancersorbed/gsand
0.00
0.01
0.02
0.04
0 100 200 300
polyamine
0.00
0.01
0.02
0.03
0.00 100.00 200.00 300.00
polyDADMAC