The Experts below are selected from a list of 117 Experts worldwide ranked by ideXlab platform
Deirdre Cabooter - One of the best experts on this subject based on the ideXlab platform.
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pilot scale evaluation of ozone as a polishing step for the removal of nonylphenol from Tank Truck cleaning wastewater
Journal of Environmental Management, 2021Co-Authors: Maarten Nagels, Sven Poelmans, Jan Dries, Nico Lambert, Pieter Van Aken, Lise Appels, Barbara Rossi, Deirdre Cabooter, Raf DewilAbstract:Abstract The presence of nonylphenol (NP) in the wastewater of the Tank Truck cleaning industry is a major concern because of its endocrine disruptive properties. In this paper, the use of ozone for degrading NP from Tank Truck cleaning wastewater was investigated by operating a pilot-scale biological wastewater treatment in combination with an ozonation unit. The impact of the added ozonation step on the removal of NP, soluble chemical oxygen demand (sCOD) and total organic carbon (TOC) was monitored over one year. sCOD and TOC removal were not significantly enhanced, but the NP peak concentrations in the effluent were significantly lower than those obtained after biological treatment only: a relatively low NP concentration was observed, even when peak loads were present in the influent of the pilot-scale biological wastewater treatment plant (influentbio). Contrariwise, the effluent of the sole biological treatment follows the peak load trends of the influentbio. During the ozonation period, the average NP concentration in the combined biological-ozone unit was 0.29 μg/L, compared to 1.89 μg/L for the effluent obtained after a sole biological treatment, resulting in an improved average removal efficiency of 32%.
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Effect of ozonation as pre-treatment and polishing step on removal of ecotoxicity and alkylphenol ethoxylates from Tank Truck cleaning wastewater
Journal of Water Process Engineering, 2020Co-Authors: Sven Poelmans, Maarten Nagels, Deirdre Cabooter, Raf Dewil, Mélanie Mignot, Jan DriesAbstract:Wastewater originating from Tank Truck cleaning (TTC) industry is reputed for its large variability and may lead to emission of recalcitrant and ecotoxic substances in discharge waters. In this study, TTC wastewater was biologically treated in two lab-scale activated sludge sequencing batch reactors. Two strategies were used, (1) influent pre-treatment with ozone followed by activated sludge treatment and (2) activated sludge treatment followed by polishing with ozone. Effluent soluble chemical oxygen demand (sCOD), ecotoxicity and the 4-nonylphenol (NP) concentration were used to evaluate and compare both strategies. Experiments were conducted for two different TTC companies using the same set-up. For Company 1, a decrease in ecotoxicity of 80 % was observed for algal growth inhibition and 10 % for Daphnia immobilization when using effluent polishing compared to pre-treatment. Hereby the NP concentration decreased below discharge limits (0.3 ng.mL−1). For Company 2 the ecotoxic effect in the algal growth inhibition test increased to 100 % when conducting effluent polishing, while ecotoxicity for the original effluent and the effluent from the pre-treated system were similar. sCOD did not decrease significantly and the discharge limit of NP was only met for one sample. Extended (7 h) effluent ozone polishing tests were conducted at two pH setpoints to assess the impact of radical formation during ozone treatment. In general, it was observed that ozone as a pre-treatment step had no significant influence on ecotoxicity and COD removal. Effluent polishing can improve ecotoxicity and effluent characteristics, despite the dependence on wastewater composition, as toxic side products may be produced.
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Fast liquid chromatography-tandem mass spectrometry methodology for the analysis of alkylphenols and their ethoxylates in wastewater samples from the Tank Truck cleaning industry
Analytical and Bioanalytical Chemistry, 2019Co-Authors: Mélanie Mignot, Maarten Nagels, Sven Poelmans, Jan Dries, Alexander Kensert, Raf Dewii, Deirdre CabooterAbstract:A fast methodology to quantify 4- tert -octylphenol (4-t-OP) and 4-nonylphenol (4-NP) and their mono- and di-ethoxylates was developed, validated, and applied to real wastewater samples. Dispersive liquid-liquid microextraction was employed as a sample preparation step, leading to a pre-concentration factor of roughly 30. Analysis was carried out by liquid chromatography-tandem mass spectrometry with electrospray ionisation in multiple reaction monitoring mode. Average recoveries were generally between 80 and 120% for both the alkylphenols and their mono- and di-ethoxylates in influent and effluent wastewater. A minimum of 5 concentration levels per compound, ranging between 1 and 500 ng/mL, were prepared to construct calibration curves making use of isotopically labelled internal standards. The method presented good linearity and repeatability over the whole range of concentrations. Taking into account the concentration factor, and the recovery of the compounds, lower limits of quantification obtained in effluent wastewater were 0.04 ng/mL for 4-t-OP and 0.14 ng/mL for 4-NP, complying with European regulations, and between 0.03 ng/mL and 0.39 ng/mL for the ethoxylates. In influent wastewater, these limits were slightly higher. The total run time of 5 min for the alkylphenols and 8 min for the ethoxylates ensured high throughput. The developed method was applied to determine 4-t-OP and 4-NP and their mono- and di-ethoxylates in wastewater from several Tank Truck cleaning companies, which was subjected to ozonation and/or biological treatment. It was demonstrated that ozonation was best applied after the biological treatment, since in this case, the biological treatment could degrade most of the biodegradable organic matter, after which ozone could react directly with the recalcitrant organic pollutants. In this case, the concentrations of the target compounds in the wastewater of the investigated company decreased below the legally allowed concentration of the European water legislation.
Jan Dries - One of the best experts on this subject based on the ideXlab platform.
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pilot scale evaluation of ozone as a polishing step for the removal of nonylphenol from Tank Truck cleaning wastewater
Journal of Environmental Management, 2021Co-Authors: Maarten Nagels, Sven Poelmans, Jan Dries, Nico Lambert, Pieter Van Aken, Lise Appels, Barbara Rossi, Deirdre Cabooter, Raf DewilAbstract:Abstract The presence of nonylphenol (NP) in the wastewater of the Tank Truck cleaning industry is a major concern because of its endocrine disruptive properties. In this paper, the use of ozone for degrading NP from Tank Truck cleaning wastewater was investigated by operating a pilot-scale biological wastewater treatment in combination with an ozonation unit. The impact of the added ozonation step on the removal of NP, soluble chemical oxygen demand (sCOD) and total organic carbon (TOC) was monitored over one year. sCOD and TOC removal were not significantly enhanced, but the NP peak concentrations in the effluent were significantly lower than those obtained after biological treatment only: a relatively low NP concentration was observed, even when peak loads were present in the influent of the pilot-scale biological wastewater treatment plant (influentbio). Contrariwise, the effluent of the sole biological treatment follows the peak load trends of the influentbio. During the ozonation period, the average NP concentration in the combined biological-ozone unit was 0.29 μg/L, compared to 1.89 μg/L for the effluent obtained after a sole biological treatment, resulting in an improved average removal efficiency of 32%.
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Effect of ozonation as pre-treatment and polishing step on removal of ecotoxicity and alkylphenol ethoxylates from Tank Truck cleaning wastewater
Journal of Water Process Engineering, 2020Co-Authors: Sven Poelmans, Maarten Nagels, Deirdre Cabooter, Raf Dewil, Mélanie Mignot, Jan DriesAbstract:Wastewater originating from Tank Truck cleaning (TTC) industry is reputed for its large variability and may lead to emission of recalcitrant and ecotoxic substances in discharge waters. In this study, TTC wastewater was biologically treated in two lab-scale activated sludge sequencing batch reactors. Two strategies were used, (1) influent pre-treatment with ozone followed by activated sludge treatment and (2) activated sludge treatment followed by polishing with ozone. Effluent soluble chemical oxygen demand (sCOD), ecotoxicity and the 4-nonylphenol (NP) concentration were used to evaluate and compare both strategies. Experiments were conducted for two different TTC companies using the same set-up. For Company 1, a decrease in ecotoxicity of 80 % was observed for algal growth inhibition and 10 % for Daphnia immobilization when using effluent polishing compared to pre-treatment. Hereby the NP concentration decreased below discharge limits (0.3 ng.mL−1). For Company 2 the ecotoxic effect in the algal growth inhibition test increased to 100 % when conducting effluent polishing, while ecotoxicity for the original effluent and the effluent from the pre-treated system were similar. sCOD did not decrease significantly and the discharge limit of NP was only met for one sample. Extended (7 h) effluent ozone polishing tests were conducted at two pH setpoints to assess the impact of radical formation during ozone treatment. In general, it was observed that ozone as a pre-treatment step had no significant influence on ecotoxicity and COD removal. Effluent polishing can improve ecotoxicity and effluent characteristics, despite the dependence on wastewater composition, as toxic side products may be produced.
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Fast liquid chromatography-tandem mass spectrometry methodology for the analysis of alkylphenols and their ethoxylates in wastewater samples from the Tank Truck cleaning industry
Analytical and Bioanalytical Chemistry, 2019Co-Authors: Mélanie Mignot, Maarten Nagels, Sven Poelmans, Jan Dries, Alexander Kensert, Raf Dewii, Deirdre CabooterAbstract:A fast methodology to quantify 4- tert -octylphenol (4-t-OP) and 4-nonylphenol (4-NP) and their mono- and di-ethoxylates was developed, validated, and applied to real wastewater samples. Dispersive liquid-liquid microextraction was employed as a sample preparation step, leading to a pre-concentration factor of roughly 30. Analysis was carried out by liquid chromatography-tandem mass spectrometry with electrospray ionisation in multiple reaction monitoring mode. Average recoveries were generally between 80 and 120% for both the alkylphenols and their mono- and di-ethoxylates in influent and effluent wastewater. A minimum of 5 concentration levels per compound, ranging between 1 and 500 ng/mL, were prepared to construct calibration curves making use of isotopically labelled internal standards. The method presented good linearity and repeatability over the whole range of concentrations. Taking into account the concentration factor, and the recovery of the compounds, lower limits of quantification obtained in effluent wastewater were 0.04 ng/mL for 4-t-OP and 0.14 ng/mL for 4-NP, complying with European regulations, and between 0.03 ng/mL and 0.39 ng/mL for the ethoxylates. In influent wastewater, these limits were slightly higher. The total run time of 5 min for the alkylphenols and 8 min for the ethoxylates ensured high throughput. The developed method was applied to determine 4-t-OP and 4-NP and their mono- and di-ethoxylates in wastewater from several Tank Truck cleaning companies, which was subjected to ozonation and/or biological treatment. It was demonstrated that ozonation was best applied after the biological treatment, since in this case, the biological treatment could degrade most of the biodegradable organic matter, after which ozone could react directly with the recalcitrant organic pollutants. In this case, the concentrations of the target compounds in the wastewater of the investigated company decreased below the legally allowed concentration of the European water legislation.
Sven Poelmans - One of the best experts on this subject based on the ideXlab platform.
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pilot scale evaluation of ozone as a polishing step for the removal of nonylphenol from Tank Truck cleaning wastewater
Journal of Environmental Management, 2021Co-Authors: Maarten Nagels, Sven Poelmans, Jan Dries, Nico Lambert, Pieter Van Aken, Lise Appels, Barbara Rossi, Deirdre Cabooter, Raf DewilAbstract:Abstract The presence of nonylphenol (NP) in the wastewater of the Tank Truck cleaning industry is a major concern because of its endocrine disruptive properties. In this paper, the use of ozone for degrading NP from Tank Truck cleaning wastewater was investigated by operating a pilot-scale biological wastewater treatment in combination with an ozonation unit. The impact of the added ozonation step on the removal of NP, soluble chemical oxygen demand (sCOD) and total organic carbon (TOC) was monitored over one year. sCOD and TOC removal were not significantly enhanced, but the NP peak concentrations in the effluent were significantly lower than those obtained after biological treatment only: a relatively low NP concentration was observed, even when peak loads were present in the influent of the pilot-scale biological wastewater treatment plant (influentbio). Contrariwise, the effluent of the sole biological treatment follows the peak load trends of the influentbio. During the ozonation period, the average NP concentration in the combined biological-ozone unit was 0.29 μg/L, compared to 1.89 μg/L for the effluent obtained after a sole biological treatment, resulting in an improved average removal efficiency of 32%.
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Effect of ozonation as pre-treatment and polishing step on removal of ecotoxicity and alkylphenol ethoxylates from Tank Truck cleaning wastewater
Journal of Water Process Engineering, 2020Co-Authors: Sven Poelmans, Maarten Nagels, Deirdre Cabooter, Raf Dewil, Mélanie Mignot, Jan DriesAbstract:Wastewater originating from Tank Truck cleaning (TTC) industry is reputed for its large variability and may lead to emission of recalcitrant and ecotoxic substances in discharge waters. In this study, TTC wastewater was biologically treated in two lab-scale activated sludge sequencing batch reactors. Two strategies were used, (1) influent pre-treatment with ozone followed by activated sludge treatment and (2) activated sludge treatment followed by polishing with ozone. Effluent soluble chemical oxygen demand (sCOD), ecotoxicity and the 4-nonylphenol (NP) concentration were used to evaluate and compare both strategies. Experiments were conducted for two different TTC companies using the same set-up. For Company 1, a decrease in ecotoxicity of 80 % was observed for algal growth inhibition and 10 % for Daphnia immobilization when using effluent polishing compared to pre-treatment. Hereby the NP concentration decreased below discharge limits (0.3 ng.mL−1). For Company 2 the ecotoxic effect in the algal growth inhibition test increased to 100 % when conducting effluent polishing, while ecotoxicity for the original effluent and the effluent from the pre-treated system were similar. sCOD did not decrease significantly and the discharge limit of NP was only met for one sample. Extended (7 h) effluent ozone polishing tests were conducted at two pH setpoints to assess the impact of radical formation during ozone treatment. In general, it was observed that ozone as a pre-treatment step had no significant influence on ecotoxicity and COD removal. Effluent polishing can improve ecotoxicity and effluent characteristics, despite the dependence on wastewater composition, as toxic side products may be produced.
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Fast liquid chromatography-tandem mass spectrometry methodology for the analysis of alkylphenols and their ethoxylates in wastewater samples from the Tank Truck cleaning industry
Analytical and Bioanalytical Chemistry, 2019Co-Authors: Mélanie Mignot, Maarten Nagels, Sven Poelmans, Jan Dries, Alexander Kensert, Raf Dewii, Deirdre CabooterAbstract:A fast methodology to quantify 4- tert -octylphenol (4-t-OP) and 4-nonylphenol (4-NP) and their mono- and di-ethoxylates was developed, validated, and applied to real wastewater samples. Dispersive liquid-liquid microextraction was employed as a sample preparation step, leading to a pre-concentration factor of roughly 30. Analysis was carried out by liquid chromatography-tandem mass spectrometry with electrospray ionisation in multiple reaction monitoring mode. Average recoveries were generally between 80 and 120% for both the alkylphenols and their mono- and di-ethoxylates in influent and effluent wastewater. A minimum of 5 concentration levels per compound, ranging between 1 and 500 ng/mL, were prepared to construct calibration curves making use of isotopically labelled internal standards. The method presented good linearity and repeatability over the whole range of concentrations. Taking into account the concentration factor, and the recovery of the compounds, lower limits of quantification obtained in effluent wastewater were 0.04 ng/mL for 4-t-OP and 0.14 ng/mL for 4-NP, complying with European regulations, and between 0.03 ng/mL and 0.39 ng/mL for the ethoxylates. In influent wastewater, these limits were slightly higher. The total run time of 5 min for the alkylphenols and 8 min for the ethoxylates ensured high throughput. The developed method was applied to determine 4-t-OP and 4-NP and their mono- and di-ethoxylates in wastewater from several Tank Truck cleaning companies, which was subjected to ozonation and/or biological treatment. It was demonstrated that ozonation was best applied after the biological treatment, since in this case, the biological treatment could degrade most of the biodegradable organic matter, after which ozone could react directly with the recalcitrant organic pollutants. In this case, the concentrations of the target compounds in the wastewater of the investigated company decreased below the legally allowed concentration of the European water legislation.
Maarten Nagels - One of the best experts on this subject based on the ideXlab platform.
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pilot scale evaluation of ozone as a polishing step for the removal of nonylphenol from Tank Truck cleaning wastewater
Journal of Environmental Management, 2021Co-Authors: Maarten Nagels, Sven Poelmans, Jan Dries, Nico Lambert, Pieter Van Aken, Lise Appels, Barbara Rossi, Deirdre Cabooter, Raf DewilAbstract:Abstract The presence of nonylphenol (NP) in the wastewater of the Tank Truck cleaning industry is a major concern because of its endocrine disruptive properties. In this paper, the use of ozone for degrading NP from Tank Truck cleaning wastewater was investigated by operating a pilot-scale biological wastewater treatment in combination with an ozonation unit. The impact of the added ozonation step on the removal of NP, soluble chemical oxygen demand (sCOD) and total organic carbon (TOC) was monitored over one year. sCOD and TOC removal were not significantly enhanced, but the NP peak concentrations in the effluent were significantly lower than those obtained after biological treatment only: a relatively low NP concentration was observed, even when peak loads were present in the influent of the pilot-scale biological wastewater treatment plant (influentbio). Contrariwise, the effluent of the sole biological treatment follows the peak load trends of the influentbio. During the ozonation period, the average NP concentration in the combined biological-ozone unit was 0.29 μg/L, compared to 1.89 μg/L for the effluent obtained after a sole biological treatment, resulting in an improved average removal efficiency of 32%.
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Effect of ozonation as pre-treatment and polishing step on removal of ecotoxicity and alkylphenol ethoxylates from Tank Truck cleaning wastewater
Journal of Water Process Engineering, 2020Co-Authors: Sven Poelmans, Maarten Nagels, Deirdre Cabooter, Raf Dewil, Mélanie Mignot, Jan DriesAbstract:Wastewater originating from Tank Truck cleaning (TTC) industry is reputed for its large variability and may lead to emission of recalcitrant and ecotoxic substances in discharge waters. In this study, TTC wastewater was biologically treated in two lab-scale activated sludge sequencing batch reactors. Two strategies were used, (1) influent pre-treatment with ozone followed by activated sludge treatment and (2) activated sludge treatment followed by polishing with ozone. Effluent soluble chemical oxygen demand (sCOD), ecotoxicity and the 4-nonylphenol (NP) concentration were used to evaluate and compare both strategies. Experiments were conducted for two different TTC companies using the same set-up. For Company 1, a decrease in ecotoxicity of 80 % was observed for algal growth inhibition and 10 % for Daphnia immobilization when using effluent polishing compared to pre-treatment. Hereby the NP concentration decreased below discharge limits (0.3 ng.mL−1). For Company 2 the ecotoxic effect in the algal growth inhibition test increased to 100 % when conducting effluent polishing, while ecotoxicity for the original effluent and the effluent from the pre-treated system were similar. sCOD did not decrease significantly and the discharge limit of NP was only met for one sample. Extended (7 h) effluent ozone polishing tests were conducted at two pH setpoints to assess the impact of radical formation during ozone treatment. In general, it was observed that ozone as a pre-treatment step had no significant influence on ecotoxicity and COD removal. Effluent polishing can improve ecotoxicity and effluent characteristics, despite the dependence on wastewater composition, as toxic side products may be produced.
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Fast liquid chromatography-tandem mass spectrometry methodology for the analysis of alkylphenols and their ethoxylates in wastewater samples from the Tank Truck cleaning industry
Analytical and Bioanalytical Chemistry, 2019Co-Authors: Mélanie Mignot, Maarten Nagels, Sven Poelmans, Jan Dries, Alexander Kensert, Raf Dewii, Deirdre CabooterAbstract:A fast methodology to quantify 4- tert -octylphenol (4-t-OP) and 4-nonylphenol (4-NP) and their mono- and di-ethoxylates was developed, validated, and applied to real wastewater samples. Dispersive liquid-liquid microextraction was employed as a sample preparation step, leading to a pre-concentration factor of roughly 30. Analysis was carried out by liquid chromatography-tandem mass spectrometry with electrospray ionisation in multiple reaction monitoring mode. Average recoveries were generally between 80 and 120% for both the alkylphenols and their mono- and di-ethoxylates in influent and effluent wastewater. A minimum of 5 concentration levels per compound, ranging between 1 and 500 ng/mL, were prepared to construct calibration curves making use of isotopically labelled internal standards. The method presented good linearity and repeatability over the whole range of concentrations. Taking into account the concentration factor, and the recovery of the compounds, lower limits of quantification obtained in effluent wastewater were 0.04 ng/mL for 4-t-OP and 0.14 ng/mL for 4-NP, complying with European regulations, and between 0.03 ng/mL and 0.39 ng/mL for the ethoxylates. In influent wastewater, these limits were slightly higher. The total run time of 5 min for the alkylphenols and 8 min for the ethoxylates ensured high throughput. The developed method was applied to determine 4-t-OP and 4-NP and their mono- and di-ethoxylates in wastewater from several Tank Truck cleaning companies, which was subjected to ozonation and/or biological treatment. It was demonstrated that ozonation was best applied after the biological treatment, since in this case, the biological treatment could degrade most of the biodegradable organic matter, after which ozone could react directly with the recalcitrant organic pollutants. In this case, the concentrations of the target compounds in the wastewater of the investigated company decreased below the legally allowed concentration of the European water legislation.
Mélanie Mignot - One of the best experts on this subject based on the ideXlab platform.
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Effect of ozonation as pre-treatment and polishing step on removal of ecotoxicity and alkylphenol ethoxylates from Tank Truck cleaning wastewater
Journal of Water Process Engineering, 2020Co-Authors: Sven Poelmans, Maarten Nagels, Deirdre Cabooter, Raf Dewil, Mélanie Mignot, Jan DriesAbstract:Wastewater originating from Tank Truck cleaning (TTC) industry is reputed for its large variability and may lead to emission of recalcitrant and ecotoxic substances in discharge waters. In this study, TTC wastewater was biologically treated in two lab-scale activated sludge sequencing batch reactors. Two strategies were used, (1) influent pre-treatment with ozone followed by activated sludge treatment and (2) activated sludge treatment followed by polishing with ozone. Effluent soluble chemical oxygen demand (sCOD), ecotoxicity and the 4-nonylphenol (NP) concentration were used to evaluate and compare both strategies. Experiments were conducted for two different TTC companies using the same set-up. For Company 1, a decrease in ecotoxicity of 80 % was observed for algal growth inhibition and 10 % for Daphnia immobilization when using effluent polishing compared to pre-treatment. Hereby the NP concentration decreased below discharge limits (0.3 ng.mL−1). For Company 2 the ecotoxic effect in the algal growth inhibition test increased to 100 % when conducting effluent polishing, while ecotoxicity for the original effluent and the effluent from the pre-treated system were similar. sCOD did not decrease significantly and the discharge limit of NP was only met for one sample. Extended (7 h) effluent ozone polishing tests were conducted at two pH setpoints to assess the impact of radical formation during ozone treatment. In general, it was observed that ozone as a pre-treatment step had no significant influence on ecotoxicity and COD removal. Effluent polishing can improve ecotoxicity and effluent characteristics, despite the dependence on wastewater composition, as toxic side products may be produced.
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Fast liquid chromatography-tandem mass spectrometry methodology for the analysis of alkylphenols and their ethoxylates in wastewater samples from the Tank Truck cleaning industry
Analytical and Bioanalytical Chemistry, 2019Co-Authors: Mélanie Mignot, Maarten Nagels, Sven Poelmans, Jan Dries, Alexander Kensert, Raf Dewii, Deirdre CabooterAbstract:A fast methodology to quantify 4- tert -octylphenol (4-t-OP) and 4-nonylphenol (4-NP) and their mono- and di-ethoxylates was developed, validated, and applied to real wastewater samples. Dispersive liquid-liquid microextraction was employed as a sample preparation step, leading to a pre-concentration factor of roughly 30. Analysis was carried out by liquid chromatography-tandem mass spectrometry with electrospray ionisation in multiple reaction monitoring mode. Average recoveries were generally between 80 and 120% for both the alkylphenols and their mono- and di-ethoxylates in influent and effluent wastewater. A minimum of 5 concentration levels per compound, ranging between 1 and 500 ng/mL, were prepared to construct calibration curves making use of isotopically labelled internal standards. The method presented good linearity and repeatability over the whole range of concentrations. Taking into account the concentration factor, and the recovery of the compounds, lower limits of quantification obtained in effluent wastewater were 0.04 ng/mL for 4-t-OP and 0.14 ng/mL for 4-NP, complying with European regulations, and between 0.03 ng/mL and 0.39 ng/mL for the ethoxylates. In influent wastewater, these limits were slightly higher. The total run time of 5 min for the alkylphenols and 8 min for the ethoxylates ensured high throughput. The developed method was applied to determine 4-t-OP and 4-NP and their mono- and di-ethoxylates in wastewater from several Tank Truck cleaning companies, which was subjected to ozonation and/or biological treatment. It was demonstrated that ozonation was best applied after the biological treatment, since in this case, the biological treatment could degrade most of the biodegradable organic matter, after which ozone could react directly with the recalcitrant organic pollutants. In this case, the concentrations of the target compounds in the wastewater of the investigated company decreased below the legally allowed concentration of the European water legislation.
