Abstract In this study, activated carbon produced from cassava peel (CP) via carbonization at 400°C was utilized as a biosorbent for the removal of chloride (Cl − ) and total hardness (TH) from groundwater. A response surface methodology (RSM) employing a Box–Behnken design (BBD) was implemented to optimize process parameters, including pH (3–10), biosorbent dosage (1–10 g), contact time (10–60 min), initial Cl − concentration (50–2000 mg/L), and initial TH concentration (40–900 mg/L). The biosorbent was applied in a batch reactor setup to evaluate its performance in removing Cl − and TH from groundwater under the optimized conditions. The experimental data showed good agreement with the model predictions, exhibiting R 2 of 0.991 and 0.905 for Cl − and TH removal, respectively. The CP biosorbent removed Cl − (245 mg/L) and TH (321 mg/L) by 84% and 90%, respectively, under optimal conditions of 6.9 g CP dose, 19.6 min, and initial pH of 8.1. The sorption kinetics followed a pseudo‐second‐order, and the equilibrium data fit the Freundlich and Langmuir models to Cl − and TH, respectively. The removal of Cl − and TH exhibited maximum adsorption capacities ( q m ) of 31.25 and 6.57 mg/g for Cl − and TH, respectively. Overall, CP shows potential as an adsorbent for remediating groundwater containing Cl − and TH.
{"title":"Simultaneous removal of chloride and hardness from groundwater by cassava peel biosorption: Optimization and sorption studies","authors":"Magori Jackson Nyangi","doi":"10.1002/rem.21770","DOIUrl":"https://doi.org/10.1002/rem.21770","url":null,"abstract":"Abstract In this study, activated carbon produced from cassava peel (CP) via carbonization at 400°C was utilized as a biosorbent for the removal of chloride (Cl − ) and total hardness (TH) from groundwater. A response surface methodology (RSM) employing a Box–Behnken design (BBD) was implemented to optimize process parameters, including pH (3–10), biosorbent dosage (1–10 g), contact time (10–60 min), initial Cl − concentration (50–2000 mg/L), and initial TH concentration (40–900 mg/L). The biosorbent was applied in a batch reactor setup to evaluate its performance in removing Cl − and TH from groundwater under the optimized conditions. The experimental data showed good agreement with the model predictions, exhibiting R 2 of 0.991 and 0.905 for Cl − and TH removal, respectively. The CP biosorbent removed Cl − (245 mg/L) and TH (321 mg/L) by 84% and 90%, respectively, under optimal conditions of 6.9 g CP dose, 19.6 min, and initial pH of 8.1. The sorption kinetics followed a pseudo‐second‐order, and the equilibrium data fit the Freundlich and Langmuir models to Cl − and TH, respectively. The removal of Cl − and TH exhibited maximum adsorption capacities ( q m ) of 31.25 and 6.57 mg/g for Cl − and TH, respectively. Overall, CP shows potential as an adsorbent for remediating groundwater containing Cl − and TH.","PeriodicalId":46411,"journal":{"name":"Remediation-The Journal of Environmental Cleanup Costs Technologies & Techniques","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135617012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andres Lancheros, Osmar Brito, Maria de Fátima Guimarães
Abstract Soil contamination caused by fossil fuels and biofuels can alter the chemical and physical properties of soil, limiting its use for agricultural, residential, and recreational purposes. Phytoremediation offers a cost‐effective and manageable solution to mitigate these environmental impacts that can be applied to large areas. The aim of this study was to evaluate Canavalia ensiformis (jack bean) growth and nutrition during the remediation of B10 biodiesel in artificially contaminated soil. The experimental design was fully randomized, with four replications and three contamination levels with B10, 0%, 1%, and 2% vol/wt, evaluated over 20, 40, and 60 days after sowing. Plant growth was assessed: shoot and root dry biomass, height, number of leaves, leaf area, and plant nutrition: macro‐ and micronutrient vegetable tissue. Dry biomass of shoots and roots, plant height, the number of leaves, and the leaf area decreased significantly in inverse proportion to the level of contamination. Twenty days after sowing, C. ensiformis growing in B10‐contaminated soil reduced the nitrogen and potassium concentrations, while phosphorus and sulfur increased, and calcium and magnesium remained unaffected. However, all except potassium tended to equilibrium after 60 days of sowing. Regarding micronutrients, manganese increased after 20 days of sowing, while iron decreased, and copper and zinc remained unchanged. Despite its growth and nutrition limitations, C. ensiformis is a viable option for phytoremediation in areas contaminated with hydrocarbons. Its nitrogen absorption capacity makes it an ideal natural fertilizer for the remediation of fuel‐contaminated soils.
{"title":"Exploring the effects of B10 biodiesel contamination on <i>Canavalia ensiformis</i> growth and nutrition in artificially contaminated soil","authors":"Andres Lancheros, Osmar Brito, Maria de Fátima Guimarães","doi":"10.1002/rem.21769","DOIUrl":"https://doi.org/10.1002/rem.21769","url":null,"abstract":"Abstract Soil contamination caused by fossil fuels and biofuels can alter the chemical and physical properties of soil, limiting its use for agricultural, residential, and recreational purposes. Phytoremediation offers a cost‐effective and manageable solution to mitigate these environmental impacts that can be applied to large areas. The aim of this study was to evaluate Canavalia ensiformis (jack bean) growth and nutrition during the remediation of B10 biodiesel in artificially contaminated soil. The experimental design was fully randomized, with four replications and three contamination levels with B10, 0%, 1%, and 2% vol/wt, evaluated over 20, 40, and 60 days after sowing. Plant growth was assessed: shoot and root dry biomass, height, number of leaves, leaf area, and plant nutrition: macro‐ and micronutrient vegetable tissue. Dry biomass of shoots and roots, plant height, the number of leaves, and the leaf area decreased significantly in inverse proportion to the level of contamination. Twenty days after sowing, C. ensiformis growing in B10‐contaminated soil reduced the nitrogen and potassium concentrations, while phosphorus and sulfur increased, and calcium and magnesium remained unaffected. However, all except potassium tended to equilibrium after 60 days of sowing. Regarding micronutrients, manganese increased after 20 days of sowing, while iron decreased, and copper and zinc remained unchanged. Despite its growth and nutrition limitations, C. ensiformis is a viable option for phytoremediation in areas contaminated with hydrocarbons. Its nitrogen absorption capacity makes it an ideal natural fertilizer for the remediation of fuel‐contaminated soils.","PeriodicalId":46411,"journal":{"name":"Remediation-The Journal of Environmental Cleanup Costs Technologies & Techniques","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136142269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Justin Miceli, Juby R. Varghese, Thomas M. Holsen, Michelle Crimi
Abstract The accumulation of significant amounts of investigation‐derived waste (IDW) from investigations of per‐ and polyfluoroalkyl substances (PFAS) contamination at active and former military installations has generated the need for viable disposal methods, which are currently limited to incineration or landfilling. Soil washing has been proposed as a more environmentally friendly alternative method to remove PFAS sorbed to IDW media, potentially allowing more cost‐effective disposal of the media as nonhazardous waste. This systematic investigation of IDW washing explored the effect of water‐, methanol‐, and salt‐based solutions, which are typically used for ion exchange (IX) resin regeneration. These solutions were tested for PFAS removal using four different field IDW solids with different pHs, total organic carbon content, and anion exchange capacity. In long washes extending to a week, distilled water was found to be effective in the removal of short‐chain PFASs (perfluorcarboxylic acids with fewer than seven fluorinated carbon atoms and perfluorosulfonic acids with fewer than six fluorinated carbon atoms) and some long‐chain PFASs including perfluorooctanoic acid, but not perfluorooctane sulfonic acid (PFOS). PFOS was only removed using water:methanol solutions with salt. Optimized 30‐min washes containing water:methanol and salt effectively removed precursors, and short‐ and long‐chain PFAS. Kinetic, soil extraction, and leaching experiments revealed that PFAS can be removed within a matter of minutes, with greater than 70% PFAS removal on the first wash; however, longer‐chain PFASs required up to three washes to be removed. Important IDW wash solution relationships influencing PFAS desorption are discussed and PFOS is proposed as an indicator species for IDW washing effectiveness. Results demonstrate that adapting components of IX regeneration solutions to IDW wash solutions facilitates an alternative means to separate PFAS contaminants from IDW, advancing PFAS remediation efforts.
{"title":"Soil washing for removal of per‐ and polyfluoroalkyl substances from investigation‐derived waste","authors":"Justin Miceli, Juby R. Varghese, Thomas M. Holsen, Michelle Crimi","doi":"10.1002/rem.21771","DOIUrl":"https://doi.org/10.1002/rem.21771","url":null,"abstract":"Abstract The accumulation of significant amounts of investigation‐derived waste (IDW) from investigations of per‐ and polyfluoroalkyl substances (PFAS) contamination at active and former military installations has generated the need for viable disposal methods, which are currently limited to incineration or landfilling. Soil washing has been proposed as a more environmentally friendly alternative method to remove PFAS sorbed to IDW media, potentially allowing more cost‐effective disposal of the media as nonhazardous waste. This systematic investigation of IDW washing explored the effect of water‐, methanol‐, and salt‐based solutions, which are typically used for ion exchange (IX) resin regeneration. These solutions were tested for PFAS removal using four different field IDW solids with different pHs, total organic carbon content, and anion exchange capacity. In long washes extending to a week, distilled water was found to be effective in the removal of short‐chain PFASs (perfluorcarboxylic acids with fewer than seven fluorinated carbon atoms and perfluorosulfonic acids with fewer than six fluorinated carbon atoms) and some long‐chain PFASs including perfluorooctanoic acid, but not perfluorooctane sulfonic acid (PFOS). PFOS was only removed using water:methanol solutions with salt. Optimized 30‐min washes containing water:methanol and salt effectively removed precursors, and short‐ and long‐chain PFAS. Kinetic, soil extraction, and leaching experiments revealed that PFAS can be removed within a matter of minutes, with greater than 70% PFAS removal on the first wash; however, longer‐chain PFASs required up to three washes to be removed. Important IDW wash solution relationships influencing PFAS desorption are discussed and PFOS is proposed as an indicator species for IDW washing effectiveness. Results demonstrate that adapting components of IX regeneration solutions to IDW wash solutions facilitates an alternative means to separate PFAS contaminants from IDW, advancing PFAS remediation efforts.","PeriodicalId":46411,"journal":{"name":"Remediation-The Journal of Environmental Cleanup Costs Technologies & Techniques","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136114628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Studies performed by Burns et al. in 2021 and 2022 demonstrated that a three‐stage batch‐wise adsorptive bubble separation process, surface active foam fractionation (SAFF), is effective at removing most per‐ and polyfluoroalkyl substances (PFASs) from contaminated groundwaters and landfill leachates. However, PFAS species with very low adsorption coefficients to bubble surfaces are difficult to remove, which is parallel to the difficulties in removing short‐chain PFAS in granulated activated carbon beds and other solid media. It is well known that the adsorption coefficient to bubble surfaces improves in the presence of electrolytes in solution and it has previously been shown that this improves the removal of PFAS. By developing a correlation for the removal percentage of one species or another of PFAS due to SAFF in commercial‐scale processes as a function of the adsorption coefficient, it is possible to generally estimate the removal percentage of any PFAS. The addition of a cationic co‐surfactant, cetrimonium bromide, to the feed can significantly further improve the adsorption coefficient and, as a consequence, materially improve the removal of short‐chain PFAS due to SAFF. A method for estimating this improved performance is in qualitative agreement with plant trials of SAFF at a North American site with a history of groundwater contamination due to the use of aqueous film forming foams firefighting foams, but the precise improvements appear to be dependent upon the concentration of the added co‐surfactant. The required concentration of co‐surfactant is significantly larger than might be expected on charge equivalence considerations, and this may be due to its consumption by other species in the feed, including PFAS that have not been accounted for. It is noted that the SAFF process may not be true foam fractionation and may, instead, be a bubble fractionator, both of which can be collectively described by the term “adsorptive bubble separation processes.”
{"title":"Commercial‐scale removal of short‐chain PFAS in a batch‐wise adsorptive bubble separation process by dosing with cationic co‐surfactant","authors":"Paul Stevenson, Stoyan I. Karakashev","doi":"10.1002/rem.21767","DOIUrl":"https://doi.org/10.1002/rem.21767","url":null,"abstract":"Abstract Studies performed by Burns et al. in 2021 and 2022 demonstrated that a three‐stage batch‐wise adsorptive bubble separation process, surface active foam fractionation (SAFF), is effective at removing most per‐ and polyfluoroalkyl substances (PFASs) from contaminated groundwaters and landfill leachates. However, PFAS species with very low adsorption coefficients to bubble surfaces are difficult to remove, which is parallel to the difficulties in removing short‐chain PFAS in granulated activated carbon beds and other solid media. It is well known that the adsorption coefficient to bubble surfaces improves in the presence of electrolytes in solution and it has previously been shown that this improves the removal of PFAS. By developing a correlation for the removal percentage of one species or another of PFAS due to SAFF in commercial‐scale processes as a function of the adsorption coefficient, it is possible to generally estimate the removal percentage of any PFAS. The addition of a cationic co‐surfactant, cetrimonium bromide, to the feed can significantly further improve the adsorption coefficient and, as a consequence, materially improve the removal of short‐chain PFAS due to SAFF. A method for estimating this improved performance is in qualitative agreement with plant trials of SAFF at a North American site with a history of groundwater contamination due to the use of aqueous film forming foams firefighting foams, but the precise improvements appear to be dependent upon the concentration of the added co‐surfactant. The required concentration of co‐surfactant is significantly larger than might be expected on charge equivalence considerations, and this may be due to its consumption by other species in the feed, including PFAS that have not been accounted for. It is noted that the SAFF process may not be true foam fractionation and may, instead, be a bubble fractionator, both of which can be collectively described by the term “adsorptive bubble separation processes.”","PeriodicalId":46411,"journal":{"name":"Remediation-The Journal of Environmental Cleanup Costs Technologies & Techniques","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136060654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Brownfields are viewed as an opportunity for sustainable development. Researchers across the world have argued about the benefits of brownfield redevelopment. However, India is still in the initial stages of defining brownfields, as no attempts have ever been made by researchers to define it and no definition is available for it in the Indian context. The main objective of this study is to derive a definition for a brownfield and fill the gap. We used the Delphi technique involving a panel of experts from relevant fields posted in governmental agencies and organizations. A list of eight keywords, derived from the definition of brownfields from various countries, and two keywords recommended by experts were rated in multiple rounds. Statistical validation for the responses was established using gray relational analysis and relative to identified distribution (RIDIT) analysis. A significant finding of this study is the importance given by the Indian experts to the “condition of the land” while attempting to define a brownfield. With a proposed definition “previously used, derelict, or polluted land is identified as a brownfield,” this research represents an attempt to provide further avenues for research on brownfields for sustainable cities in India.
{"title":"Defining the term “Brownfield” in India","authors":"Nihal S. Verma, Haimanti Banerji","doi":"10.1002/rem.21768","DOIUrl":"https://doi.org/10.1002/rem.21768","url":null,"abstract":"Brownfields are viewed as an opportunity for sustainable development. Researchers across the world have argued about the benefits of brownfield redevelopment. However, India is still in the initial stages of defining brownfields, as no attempts have ever been made by researchers to define it and no definition is available for it in the Indian context. The main objective of this study is to derive a definition for a brownfield and fill the gap. We used the Delphi technique involving a panel of experts from relevant fields posted in governmental agencies and organizations. A list of eight keywords, derived from the definition of brownfields from various countries, and two keywords recommended by experts were rated in multiple rounds. Statistical validation for the responses was established using gray relational analysis and relative to identified distribution (RIDIT) analysis. A significant finding of this study is the importance given by the Indian experts to the “condition of the land” while attempting to define a brownfield. With a proposed definition “previously used, derelict, or polluted land is identified as a brownfield,” this research represents an attempt to provide further avenues for research on brownfields for sustainable cities in India.","PeriodicalId":46411,"journal":{"name":"Remediation-The Journal of Environmental Cleanup Costs Technologies & Techniques","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43905169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Because of the remarkable chemical structure of perfluoroalkyl and polyfluoroalkyl substances (PFAS), as well as the complex conditions of water, selecting an appropriate adsorbent for treating PFAS is critical. Adsorption needs to be environmentally friendly, low cost, and consider the types of adsorbents that work well in mixed PFAS solutions. In the present study, we used mixed PFAS to estimate the PFAS activity. This research aimed to evaluate and compare the efficacy of the adsorption of PFAS from water using different adsorbents: granular activated carbon (GAC), IRA 910 (strong anion resin), and DOWEX MB‐50 (mixed exchange resin). Batch adsorption isotherms and kinetic studies were performed for perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), and perfluorohexane sulfonic acid (PFHxS). Freundlich models consistently described the kinetic behavior with a high correlation coefficient (R2 > 0.98). PFAS adsorption capacities on GAC and IRA910 were dependent on the chain length (PFOS > PFOA > PFHxS). The adsorption capacity of DOWEX MB‐50 decreased because of the sulfonate effects (PFOS > PFHxS > PFOA). The rate constants (k2) that represented the adsorption of PFAS on different adsorbents observed within 96 h were accurately determined by the pseudo‐second‐order (PSO) model. GAC achieved followed the relationship k2(PFOS) > k2(PFOA) > k2(PFHxS). Furthermore, k2 of IRA910 decreased in the order of k2(PFOA) > k2(PFOS) > k2(PFHxS), implying that IRA910 promoted hydrophobicity more significantly on the adsorption of PFCAs than perfluoroalkane (‐alkyl) sulfonic acids. The kinetics of DOWEX MB‐50 revealed k2(PFHxS) > k2(PFOS) > k2(PFOA) because gel‐type resins like DOWEX MB‐50 are more suitable for shorter‐chain PFAS. Further investigation is needed to determine the effect of organic matter under natural conditions and evaluate adsorptive selection caused by operational complexities.
{"title":"Evaluation of the adsorption behavior of mixed perfluoroalkyl and polyfluoroalkyl substances onto granular activated carbon and Styrene‐divinylbenzene resins","authors":"S. Sukeesan, N. Boontanon, S. Fujii, S. Boontanon","doi":"10.1002/rem.21766","DOIUrl":"https://doi.org/10.1002/rem.21766","url":null,"abstract":"Because of the remarkable chemical structure of perfluoroalkyl and polyfluoroalkyl substances (PFAS), as well as the complex conditions of water, selecting an appropriate adsorbent for treating PFAS is critical. Adsorption needs to be environmentally friendly, low cost, and consider the types of adsorbents that work well in mixed PFAS solutions. In the present study, we used mixed PFAS to estimate the PFAS activity. This research aimed to evaluate and compare the efficacy of the adsorption of PFAS from water using different adsorbents: granular activated carbon (GAC), IRA 910 (strong anion resin), and DOWEX MB‐50 (mixed exchange resin). Batch adsorption isotherms and kinetic studies were performed for perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), and perfluorohexane sulfonic acid (PFHxS). Freundlich models consistently described the kinetic behavior with a high correlation coefficient (R2 > 0.98). PFAS adsorption capacities on GAC and IRA910 were dependent on the chain length (PFOS > PFOA > PFHxS). The adsorption capacity of DOWEX MB‐50 decreased because of the sulfonate effects (PFOS > PFHxS > PFOA). The rate constants (k2) that represented the adsorption of PFAS on different adsorbents observed within 96 h were accurately determined by the pseudo‐second‐order (PSO) model. GAC achieved followed the relationship k2(PFOS) > k2(PFOA) > k2(PFHxS). Furthermore, k2 of IRA910 decreased in the order of k2(PFOA) > k2(PFOS) > k2(PFHxS), implying that IRA910 promoted hydrophobicity more significantly on the adsorption of PFCAs than perfluoroalkane (‐alkyl) sulfonic acids. The kinetics of DOWEX MB‐50 revealed k2(PFHxS) > k2(PFOS) > k2(PFOA) because gel‐type resins like DOWEX MB‐50 are more suitable for shorter‐chain PFAS. Further investigation is needed to determine the effect of organic matter under natural conditions and evaluate adsorptive selection caused by operational complexities.","PeriodicalId":46411,"journal":{"name":"Remediation-The Journal of Environmental Cleanup Costs Technologies & Techniques","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44242449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Timothy Boe, W. Calfee, P. Lemieux, S. Serre, A. Abdel-Hady, M. Monge, D. Aslett, Bruce Akers, J. Howard
This study evaluated the microbiocidal efficacy of a cleaning and disinfection (C&D) treatment using stainless‐steel coupons applied to three common types of animal mortality transport vehicles when exposed to agricultural conditions. Metal test coupons, inoculated with bacteriophage MS2, were affixed to the undercarriage of three types of animal mortality transport vehicles at various locations. Coupons were grimed by maneuvering the test vehicles down a series of wet dirt roads. Coupons were attached and extracted at various points to evaluate C&D performance with and without grime. C&D efficacy using a water‐supplied pressure washing system and a dilute sodium hypochlorite (NaOCl) solution was determined by comparing the difference in recovered viable virus between positive control coupons and test coupons. The results demonstrated a relatively high surface decontamination efficacy, with all but one location showing >5 log reduction of MS2. Coupons located on the roll‐off truck's inside‐back bumper contained the highest level of grime and resulted in a 4 log reduction of MS2. There was no significant difference in C&D efficacy across vehicle types, but locations impacted by grime and lack of accessibility achieved lower efficacies on average. These findings suggest that common C&D protocols, when applied to farm mortality transport vehicles, are effective. Hard‐to‐access locations containing high levels of grime may be candidates for additional targeted treatment.
{"title":"Evaluation of cleaning and disinfection protocols for commercial farm equipment following a foreign animal disease outbreak","authors":"Timothy Boe, W. Calfee, P. Lemieux, S. Serre, A. Abdel-Hady, M. Monge, D. Aslett, Bruce Akers, J. Howard","doi":"10.1002/rem.21762","DOIUrl":"https://doi.org/10.1002/rem.21762","url":null,"abstract":"This study evaluated the microbiocidal efficacy of a cleaning and disinfection (C&D) treatment using stainless‐steel coupons applied to three common types of animal mortality transport vehicles when exposed to agricultural conditions. Metal test coupons, inoculated with bacteriophage MS2, were affixed to the undercarriage of three types of animal mortality transport vehicles at various locations. Coupons were grimed by maneuvering the test vehicles down a series of wet dirt roads. Coupons were attached and extracted at various points to evaluate C&D performance with and without grime. C&D efficacy using a water‐supplied pressure washing system and a dilute sodium hypochlorite (NaOCl) solution was determined by comparing the difference in recovered viable virus between positive control coupons and test coupons. The results demonstrated a relatively high surface decontamination efficacy, with all but one location showing >5 log reduction of MS2. Coupons located on the roll‐off truck's inside‐back bumper contained the highest level of grime and resulted in a 4 log reduction of MS2. There was no significant difference in C&D efficacy across vehicle types, but locations impacted by grime and lack of accessibility achieved lower efficacies on average. These findings suggest that common C&D protocols, when applied to farm mortality transport vehicles, are effective. Hard‐to‐access locations containing high levels of grime may be candidates for additional targeted treatment.","PeriodicalId":46411,"journal":{"name":"Remediation-The Journal of Environmental Cleanup Costs Technologies & Techniques","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45275163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chlorinated organics have been frequently detected in groundwaters, threatening the quality of drinking water supplies worldwide. A promising method for groundwater remediation involves reductive dechlorination (RD), in which chlorine atoms are sequentially removed and substituted by hydrogen, producing less harmful byproducts. In this paper, for the first time, RD research is reviewed in light of the growing incorporation of density functional theory (DFT) as a research tool. DFT has been used to uncover a variety of reaction properties for a range of relevant groundwater pollutants, including 1,2,3‐trichloropropane, hexachlorobenzene, and various dioxins. DFT models have revealed the role of surface interactions in driving the kinetics of catalytically driven RD. Mechanisms involved with biologically mediated RD have also been elucidated with insights gleaned from DFT. Issues and challenges for future research are also discussed.
{"title":"Integrating density functional theory into reductive dechlorination research","authors":"Jaya Das Schober, S. Kurwadkar, W. Harper","doi":"10.1002/rem.21765","DOIUrl":"https://doi.org/10.1002/rem.21765","url":null,"abstract":"Chlorinated organics have been frequently detected in groundwaters, threatening the quality of drinking water supplies worldwide. A promising method for groundwater remediation involves reductive dechlorination (RD), in which chlorine atoms are sequentially removed and substituted by hydrogen, producing less harmful byproducts. In this paper, for the first time, RD research is reviewed in light of the growing incorporation of density functional theory (DFT) as a research tool. DFT has been used to uncover a variety of reaction properties for a range of relevant groundwater pollutants, including 1,2,3‐trichloropropane, hexachlorobenzene, and various dioxins. DFT models have revealed the role of surface interactions in driving the kinetics of catalytically driven RD. Mechanisms involved with biologically mediated RD have also been elucidated with insights gleaned from DFT. Issues and challenges for future research are also discussed.","PeriodicalId":46411,"journal":{"name":"Remediation-The Journal of Environmental Cleanup Costs Technologies & Techniques","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43328776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The emergence of synthetic micropollutants in wastewater due to domestic and industrial use has presented new challenges for treatment processes. Among these pollutants, pharmaceutical and personal care products (PPCPs) are considered emerging contaminants due to their potential to enter drinking water sources. Antibiotics, in particular, are of significant concern due to their high consumption in veterinary and human applications. In this study, the electrocoagulation (EC) process is used as an efficient technique for the removal of cephalexin (CFX) from pharmaceutical wastewater. The study aims to explore the ability of the EC process to remove CFX and optimize its performance using the response surface method based on Central Composite Design (RSM‐CCD). The effects of initial CFX concentration, electrolysis time, initial pH, and electrode type (non‐insulated and insulated) were considered in the optimization process. This research is distinct as it examines the influence of key factors on the elimination of CFX. The results showed that electrolysis time had the most significant effect on CFX removal using the EC process. The analysis of variance (ANOVA) test was used to evaluate the importance of independent variables and their interaction. The optimal operating conditions for maximum removal efficiency (86.53%) were an initial cephalexin concentration, reaction time, and initial pH of 34 mg/L, 34.35 min, and 6.5, respectively, using an insulated electrode. Under these optimal conditions, predicted cephalexin removal was 93.54%. These findings demonstrate that RSM‐CCD is a useful tool for optimizing electrochemical removal processes for micropollutants such as CFX from wastewater streams. The study highlights the importance of considering electrode type in optimizing EC processes for micropollutant removal from wastewater.
{"title":"A sustainable system for decontamination of cephalexin antibiotic using electrocoagulation technology and response surface methodology","authors":"Maliheh Arab, S. Danesh","doi":"10.1002/rem.21761","DOIUrl":"https://doi.org/10.1002/rem.21761","url":null,"abstract":"The emergence of synthetic micropollutants in wastewater due to domestic and industrial use has presented new challenges for treatment processes. Among these pollutants, pharmaceutical and personal care products (PPCPs) are considered emerging contaminants due to their potential to enter drinking water sources. Antibiotics, in particular, are of significant concern due to their high consumption in veterinary and human applications. In this study, the electrocoagulation (EC) process is used as an efficient technique for the removal of cephalexin (CFX) from pharmaceutical wastewater. The study aims to explore the ability of the EC process to remove CFX and optimize its performance using the response surface method based on Central Composite Design (RSM‐CCD). The effects of initial CFX concentration, electrolysis time, initial pH, and electrode type (non‐insulated and insulated) were considered in the optimization process. This research is distinct as it examines the influence of key factors on the elimination of CFX. The results showed that electrolysis time had the most significant effect on CFX removal using the EC process. The analysis of variance (ANOVA) test was used to evaluate the importance of independent variables and their interaction. The optimal operating conditions for maximum removal efficiency (86.53%) were an initial cephalexin concentration, reaction time, and initial pH of 34 mg/L, 34.35 min, and 6.5, respectively, using an insulated electrode. Under these optimal conditions, predicted cephalexin removal was 93.54%. These findings demonstrate that RSM‐CCD is a useful tool for optimizing electrochemical removal processes for micropollutants such as CFX from wastewater streams. The study highlights the importance of considering electrode type in optimizing EC processes for micropollutant removal from wastewater.","PeriodicalId":46411,"journal":{"name":"Remediation-The Journal of Environmental Cleanup Costs Technologies & Techniques","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48543723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shahrzad Saffari Ghandehari, Shih‐Huai Cheng, C. Hapeman, A. Torrents, B. V. Kjellerup
Trichloroethylene (TCE) is a toxic organic compound, which can adversely affect human health. The chemical is one of the most frequently found contaminants in groundwater in the United States and around the world. A landfill in Maryland contaminated with high levels of TCE decades ago was added to the National Priority List (NPL) in 1994 for clean up. A biowall was installed on the site in 2013 to promote the bioremediation of TCE and subsequently of its degradation products. Six‐year monitoring data indicated a steady removal of >99% groundwater TCE at the wall since installation. However, a concurrent buildup of intermediate byproducts was observed downgradient of the wall. An examination of the entire system was necessary to find the reason behind the inefficiency of the biowall. In this study, the background of the site, remediation plan, and installation were assessed. Monitoring data, including the concentration of TCE and its degradation byproducts, and geochemical and physical characteristics were evaluated to understand the conditions and challenges facing decision‐makers of this project and possible options to improve biowall efficacy.
{"title":"Ensuring the continued success of a mulch biowall at a trichloroethylene‐contaminated superfund site: Lessons learned","authors":"Shahrzad Saffari Ghandehari, Shih‐Huai Cheng, C. Hapeman, A. Torrents, B. V. Kjellerup","doi":"10.1002/rem.21764","DOIUrl":"https://doi.org/10.1002/rem.21764","url":null,"abstract":"Trichloroethylene (TCE) is a toxic organic compound, which can adversely affect human health. The chemical is one of the most frequently found contaminants in groundwater in the United States and around the world. A landfill in Maryland contaminated with high levels of TCE decades ago was added to the National Priority List (NPL) in 1994 for clean up. A biowall was installed on the site in 2013 to promote the bioremediation of TCE and subsequently of its degradation products. Six‐year monitoring data indicated a steady removal of >99% groundwater TCE at the wall since installation. However, a concurrent buildup of intermediate byproducts was observed downgradient of the wall. An examination of the entire system was necessary to find the reason behind the inefficiency of the biowall. In this study, the background of the site, remediation plan, and installation were assessed. Monitoring data, including the concentration of TCE and its degradation byproducts, and geochemical and physical characteristics were evaluated to understand the conditions and challenges facing decision‐makers of this project and possible options to improve biowall efficacy.","PeriodicalId":46411,"journal":{"name":"Remediation-The Journal of Environmental Cleanup Costs Technologies & Techniques","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45301278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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