Treatment of Soils Contaminated with γ-Hexachlorocyclohexane in Sequential Methanogenic-Aerobic...
3
Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576 S559 Fig. 1. Effect of surfactant concentration on PCE solubility and liquor surface tension: (a) Solubility of PCE; (b) Surface tension. Effect of Tween 80 on Solubilization of Perchloroethylene L. Breton-Deval 1 , C.U. Moreno-Medina 1 , F. Fava 2 , E. Rios-Leal 1 , H.M. Poggi-Varaldo 1,∗ 1 Environmental Biotechnology and Renewable Energies R&D Group, Department Biotechnology & Bioengineering, CINVESTAV-I.P.N. P.O. Box 14-740, 07000, México D.F., México 2 Department of Applied Chemistry and Sciences of Materials, Faculty of Engineering, Universita di Bologna, Italy Keywords: ad situ remediation; perchloroethylene; solubility; sur- face tension; surfactant; Tween 80 E-mail address: [email protected] (H.M. Poggi-Varaldo). Introduction: One way to increase PCE availability in aquifers so it could be pumped out for ad situ remediation (Herrera-Lòpez et al., 2006, Herrera-López et al., 2007, Moreno-Medina et al., 2010) is to supply surfactants that would solubilize the pollutant. Therefore, this work aimed at evaluating the effect of Tween 80 addition on PCE solubility in water. Methods: Solubility tests were carried out in serum bottles filled with water, 1 mL PCE, and Tween concentrations at 0, 100, 200, 300, 400, 600, 800 mg/L and mixed with magnetic mixers for 2 h, 300 rpm, 25 o C. PCE in the aqueous phase was analyzed by headspace FID GC. Parameters K m and molar solubilization ratio (MSR) were calculated according to Eq. 1 and 2, respectively (Harendra and Vipulanandan, 2008) MSR = Y − Y 0 X − X 0 (1) K m (x) = Y − Y 0 Y 0 (2) where Y is the molar concentration of PCE at a given molar concen- tration of surfactant (X), Yo is the molar concentration of PCE at the critical micellar concentration (CMC) of the surfactant (Xo). Surface tension was determined with a Lauda TD1C tensiometer based on the dish technique. Results: PCE solubility linearly increased with surfactant con- centration (Fig. 1a). The absolute maximum of solubilized PCE was 1532 mg/L at 800 mg/L of Tween 80. The coefficient K m also linearly increased with the net concentration of Tween 80 and reached a maximum 4.8. The MRS remained nearly constant beyond 300 mg Tween 80/L. This was consistent with surface tension that decreased from 70 to 35 dyne/cm in the interval 0 to 300 mg Tween 80/L, and remained fairly constant beyond 300 mg/L of surfactant (Fig. 1b). Discussion: It has been reported ca. 270 and 300 mg PCE/L at 800 mg/L of sodium dodecyl sulfate and a biosurfactant UH, respec- tively (Harendra and Vipulanandan, 2008), i.e., solubility ratios of 2.90 and 3.23, respectively. On the other hand, the solubility ratio was 16.47 at 800 mg/L Tween 80 in our research. The strong sol- ubilization power of Tween 80 and its reported lack of toxicity to several microorganisms suggest that this surfactant is an attractive tool for solubilizing high concentrations of PCE in aquifers, in this way facilitating PCE extraction for ad situ remediation. Reference Harendra, S., Vipulanandan, C., 2008. Degradation of high concentrations of PCE solubilized in SDS and biosurfactant with Fe/Ni bi-metallic particles. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 322 (1–3), 6–13. Herrera-Lòpez, D.; Ríos-Leal, E.; Ponce-Noyola, M.T.; Esparza-García, F.; García- Mena, J.; Poggi-Varaldo, H.M. (2006). A comparison of two fluidized bed bioreactors with combined electron acceptors for removal of high concentra- tions of perchloroethylene. In: Sass, B.M. (Editor). Remediation of chlorinated and recalcitrant compounds-2006. Battelle Press, Columbus, OH. ISBN 1-57477r- r157-4. Herrera-López, D.; García-Mena, J.; Poggi-Varaldo, H.M. (2007). Influence of zero- valent iron addition to batch bioreactors with simultaneous electron acceptors on removal of high concentrations of perchloroethylene. In: Gavasakar, A.; Sil- ver, C. (Editors). In situ and on site remediation-2007. Battelle Press, Columbus, Ohio. Moreno-Medina, C.U.; Breton-Deval, L.; Ríos-Leal E.; Galíndez- Mayer J.; Ortega- Clemente, A.; Fava F.; Rinderknecht-Seijas, N.; Poggi-Varaldo, H.M. (2010). Effect of sudden increase of PCE concentration on performance of fluidized bed biore- actors operated in simultaneous electron acceptor modes. Submitted to this Symposium. doi:10.1016/j.jbiotec.2010.10.021 Treatment of Soils Contaminated with - Hexachlorocyclohexane in Sequential Methanogenic-Aerobic Slurry Bioreactors B. Camacho-Pérez 1 , E. Ríos-Leal 2 , J. Barrera-Cortés 3 , F. Esparza- García 4 , N. Rinderknecht-Seijas 1,2,3,4 , H.M. Poggi-Varaldo 1,∗ 1 Environmental Biotechnology and Renewable Energies R&D Group, Department Biotechnology and Bioengineering, Centro de Investi- gación y de Estudios Avanzados del Instituto Politécnico Nacional, P.O. Box 14-740, México D.F., 07000, México 2 Central Analítica, ibídem 3 Control Inteligente de Procesos, ibídem 4 ESIQIE del IPN, México E-mail address: [email protected] (H.M. Poggi-Varaldo). Introduction: Negative impacts of lindane on the environment and human health have been reported worldwide (Bachmann et al., 1988; Robles-González et al., 2008). The aim of this work was to evaluate the effect of supplementation with a readily degradable carbon source (sucrose) and the addition of silicone oil solvent on lindane removal from an agricultural soil with high contents of clay and organic matter, using lab scale batch slurry bioreactors (SB). Methodology: The soil contained 8% organic matter, 41% clay, and 100 mg lindane/kg. SBs were operated in a sequential mode (15 d methanogenic followed by 15 d aerobic, herein after M- A). The experimental design was a factorial 2 2 with co-substrate (sucrose) and silicone oil at two concentration levels (0 and 1 g/L, 0
Transcript of Treatment of Soils Contaminated with γ-Hexachlorocyclohexane in Sequential Methanogenic-Aerobic...
Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576 S559
Fig. 1. Effect of surfactant concentration on PCE solubility and liquor surface tension: (a) Solubility of PCE; (b) Surface tension.
Effect of Tween 80 on Solubilization of Perchloroethylene
L. Breton-Deval 1, C.U. Moreno-Medina 1, F. Fava 2, E. Rios-Leal 1,H.M. Poggi-Varaldo 1,∗
1 Environmental Biotechnology and Renewable Energies R&D Group,Department Biotechnology & Bioengineering, CINVESTAV-I.P.N. P.O.Box 14-740, 07000, México D.F., México2 Department of Applied Chemistry and Sciences of Materials, Facultyof Engineering, Universita di Bologna, ItalyKeywords: ad situ remediation; perchloroethylene; solubility; sur-face tension; surfactant; Tween 80
E-mail address: [email protected] (H.M. Poggi-Varaldo).
Introduction: One way to increase PCE availability in aquifers soit could be pumped out for ad situ remediation (Herrera-Lòpez etal., 2006, Herrera-López et al., 2007, Moreno-Medina et al., 2010) isto supply surfactants that would solubilize the pollutant. Therefore,this work aimed at evaluating the effect of Tween 80 addition onPCE solubility in water.
Methods: Solubility tests were carried out in serum bottlesfilled with water, 1 mL PCE, and Tween concentrations at 0, 100,200, 300, 400, 600, 800 mg/L and mixed with magnetic mixersfor 2 h, 300 rpm, 25oC. PCE in the aqueous phase was analyzedby headspace FID GC. Parameters Km and molar solubilizationratio (MSR) were calculated according to Eq. 1 and 2, respectively(Harendra and Vipulanandan, 2008)
MSR = Y − Y0
X − X0(1)
Km(x) = Y − Y0
Y0(2)
where Y is the molar concentration of PCE at a given molar concen-tration of surfactant (X), Yo is the molar concentration of PCE at thecritical micellar concentration (CMC) of the surfactant (Xo). Surfacetension was determined with a Lauda TD1C tensiometer based onthe dish technique.
Results: PCE solubility linearly increased with surfactant con-centration (Fig. 1a). The absolute maximum of solubilized PCEwas 1532 mg/L at 800 mg/L of Tween 80. The coefficient Km alsolinearly increased with the net concentration of Tween 80 andreached a maximum 4.8. The MRS remained nearly constant beyond300 mg Tween 80/L. This was consistent with surface tension thatdecreased from 70 to 35 dyne/cm in the interval 0 to 300 mg Tween80/L, and remained fairly constant beyond 300 mg/L of surfactant(Fig. 1b).
Discussion: It has been reported ca. 270 and 300 mg PCE/L at 800mg/L of sodium dodecyl sulfate and a biosurfactant UH, respec-tively (Harendra and Vipulanandan, 2008), i.e., solubility ratios of2.90 and 3.23, respectively. On the other hand, the solubility ratiowas 16.47 at 800 mg/L Tween 80 in our research. The strong sol-ubilization power of Tween 80 and its reported lack of toxicity to
several microorganisms suggest that this surfactant is an attractivetool for solubilizing high concentrations of PCE in aquifers, in thisway facilitating PCE extraction for ad situ remediation.
Reference
Harendra, S., Vipulanandan, C., 2008. Degradation of high concentrations of PCEsolubilized in SDS and biosurfactant with Fe/Ni bi-metallic particles. Colloidsand Surfaces A: Physicochemical and Engineering Aspects. 322 (1–3), 6–13.
Herrera-Lòpez, D.; Ríos-Leal, E.; Ponce-Noyola, M.T.; Esparza-García, F.; García-Mena, J.; Poggi-Varaldo, H.M. (2006). A comparison of two fluidized bedbioreactors with combined electron acceptors for removal of high concentra-tions of perchloroethylene. In: Sass, B.M. (Editor). Remediation of chlorinatedand recalcitrant compounds-2006. Battelle Press, Columbus, OH. ISBN 1-57477r-r157-4.
Herrera-López, D.; García-Mena, J.; Poggi-Varaldo, H.M. (2007). Influence of zero-valent iron addition to batch bioreactors with simultaneous electron acceptorson removal of high concentrations of perchloroethylene. In: Gavasakar, A.; Sil-ver, C. (Editors). In situ and on site remediation-2007. Battelle Press, Columbus,Ohio.
Moreno-Medina, C.U.; Breton-Deval, L.; Ríos-Leal E.; Galíndez- Mayer J.; Ortega-Clemente, A.; Fava F.; Rinderknecht-Seijas, N.; Poggi-Varaldo, H.M. (2010). Effectof sudden increase of PCE concentration on performance of fluidized bed biore-actors operated in simultaneous electron acceptor modes. Submitted to thisSymposium.
doi:10.1016/j.jbiotec.2010.10.021
Treatment of Soils Contaminated with �-Hexachlorocyclohexane in Sequential Methanogenic-AerobicSlurry Bioreactors
B. Camacho-Pérez 1, E. Ríos-Leal 2, J. Barrera-Cortés 3, F. Esparza-García 4, N. Rinderknecht-Seijas 1,2,3,4, H.M. Poggi-Varaldo 1,∗
1 Environmental Biotechnology and Renewable Energies R&D Group,Department Biotechnology and Bioengineering, Centro de Investi-gación y de Estudios Avanzados del Instituto Politécnico Nacional, P.O.Box 14-740, México D.F., 07000, México2 Central Analítica, ibídem3 Control Inteligente de Procesos, ibídem4 ESIQIE del IPN, México
E-mail address: [email protected] (H.M. Poggi-Varaldo).
Introduction: Negative impacts of lindane on the environmentand human health have been reported worldwide (Bachmann etal., 1988; Robles-González et al., 2008). The aim of this work was toevaluate the effect of supplementation with a readily degradablecarbon source (sucrose) and the addition of silicone oil solvent onlindane removal from an agricultural soil with high contents of clayand organic matter, using lab scale batch slurry bioreactors (SB).
Methodology: The soil contained 8% organic matter, 41% clay,and 100 mg lindane/kg. SBs were operated in a sequential mode(15 d methanogenic followed by 15 d aerobic, herein after M-A). The experimental design was a factorial 22 with co-substrate(sucrose) and silicone oil at two concentration levels (0 and 1 g/L, 0
S560 Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576
Fig. 1. Removals of lindane in sequential M-SR slurry bioreactors after 30 d of oper-ation. (a) with co-substrate; (b) without co-substrate. Keys: SB-MA-C sterile soilinoculated with acclimated seed and co-substrate sucrose; SB-MA-CS sterile soilinoculated with acclimated seed, co-substrate and silicone oil; SB-MA: sterile soilinoculated with acclimated seed, no solvent no cosubstrate; SB-MA-S sterile soilinoculated with acclimated seed and solvent, no cosubstrate; A: sterile soil withsterilized seed; B: live soil inoculated with sterilized seed; C: live soil inoculatedwith live seed.
and 20% v/v, respectively). All active SBs were bioaugmented withlindane-acclimated inocula from suspended growth seed bioreac-tors (methanogenic at day 0 and aerobic at day 15).
Fig. 1.Results: The ANOVA indicated that both silicone oil and sucrose
had significant positive effects on lindane removal (P < 0.05). Thebest result was obtained in SB operated in presence of silicone oiland sucrose, which yielded 82% lindane removal after 30 days ofoperation. The second stage of SB operation, the aerobic one, con-tributed more (37 to 72%, depending on the treatment) than themethanogenic stage to lindane removal (16 to 35%) (Table 1). Mainmetabolites from lindane degradation were 1,4-dichlorobenzeneand chlorobenzene as well as several unidentified more peaks(Fig. 2). Concentrations of all detected metabolites significantlydecreased during the aerobic stage.
Discussion: Sequential M-A SBs in our work showed perfor-mances superior to those reported for simultaneous M-A SBtreating the same soil (9.5 and 18% lindane reductions, Robles-González, 2008) and only M SBs (41%). Quintero et al. (2006) workedwith a sandy soil polluted with �-HCH and other isomers in ananaerobic batch SB, biostimulated with starch. They found 62%removal of �-HCH after 60 d treatment.
Finally, in our research we found distinct, beneficial effects ofboth silicone oil (solvent) and sucrose supplementation on lin-dane reduction. The first, methanogenic stage of SB operationcontributed less than the aerobic stage to lindane removal.
Uncited references
Camacho-Pérez et al., 2010.
Reference
Bachmann, A., Walet, P., Wijnen, P., De Bruin, W., Huntjens, J.L.M., Roelofsen, W.,Zehnder, A.J.B., 1988. Biodegradation of alpha- and beta hexachlorocyclohexanein a soil slurry under different redox conditions. Appl Environ Microbiol. 54,143–149.
Camacho-Pérez, B., Ríos-Leal, E., Esparza-García, F., Barrera-Cortés, J., Fava, F.,Poggi-Varaldo, H.M., 2010. Bioremediation of an agricultural soil polluted with
Table 1Stage and overall lindane removal efficiencies in this experiment. Efficiencies are expressed in decimal numbers.
Treatment �1 (0 to 15 d) Methanogenic stage �2 (15 to 30 d) Aerobic stage �0 (30 d) Sequential M-A
M-A, neither solvent nor sucrose 0.180 0.367 0.481M-A with solvent 20% v/v 0.155 0.506 0.583M-A with sucrose 1 g/L 0.195 0.450 0.558M-A with solvent and sucrose 0.352 0.718 0.817
Fig. 2. Chromatograms of the formation of intermediate metabolites in slurry reactors without oil silicone after 15 and 30 days. Peaks V,W,X,Y,Z were not identified.
Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576 S561
lindane in triphasic, sequential methanogenic-sulfate reducing slurry bioreac-tors. Abstract submitted to 14th International Biotechnology Symposium andExhibition.
Quintero, J.C., Moreira, M.T., Lema, J.M., Feijoo, G., 2006. An anaerobic bioreactorallows the efficient degradation of HCH isomers in soil slurry. Chemosphere. 63,1005–1013.
Robles-González, I.V. (2008). Biorremediación de suelos minerales orgánico-arcillosos contaminados con agroquímicos utilizando reactores de suelosactivados. Tesis de doctorado. CINVESTAV del IPN, México D.F., México.
Robles-González, I.V., Fava, F., Poggi-Varaldo, H.M., 2008. A review on slurry biore-actors for bioremediation of soils and sediments. Microbial Cell Factories 7,5.
doi:10.1016/j.jbiotec.2010.10.022
Bioremediation of an Agricultural Soil Polluted with Lindanein Triphasic, Sequential Methanogenic-Sulfate Reducing SlurryBioreactors
B. Camacho-Pérez 1, E. Ríos-Leal 2, F. Esparza-García 3, J. Barrera-Cortés 4, F. Fava 5, H.M. Poggi-Varaldo 1,∗
1 Environmental Biotechnology and Renewable Energies R&D Group,Department Biotechnology and Bioengineering, Centro de Investi-gación y de Estudios Avanzados del Instituto Politécnico Nacional, P.O.Box 14-740, 07000 México D.F., México2 Central Analítica, ibídem3 Ecología Bioquímica, ibídem4 Control inteligente de Procesos, ibídem5 Department of Applied Chemistry and Sciences of Materials, Facultyof Engineering, Universita di Bologna, Italy
E-mail address: [email protected] (H.M. Poggi-Varaldo).
Introduction: Due to the toxicity and persistence of �-HCH, envi-ronmental matrices contaminated with this compound have beentargeted for bioremediation (Robles-González, 2008; Quintero etal., 2005). Slurry bioreactors (SBs) are successfully used for ex situand ad situ treatment of contaminated soils and sludges (Robles-González et al., 2006, 2008). The purpose of this research was toevaluate the effect of solvent (silicone oil, 0 and 20% v/v) on lin-dane removal from an agricultural soil with high contents of clayand organic matter, using lab scale batch sequential methanogenic-sulfate reducing (M-SR) SBs.
Methodology: The soil contained 8% organic matter, 41% clay, and100 mg lindane/kg. SBs were operated in a sequential mode (15 d
Fig. 1. Degradation of �-HCH in sequential slurry bioreactors after 30 d operation.Keys: SB-M-SR sterile soil seeded with live acclimated inocula; SB-M-SR-S sterilesoil seeded with live acclimated inocula and silicone oil; A sterile soil with sterilisedacclimated inocula; B nonsterile soil seeded with sterilised acclimated inocula; Cnonsterile soil seeded with live acclimated inocula.
methanogenic followed by 15 sulfate reducing, herein after sequen-tial M-SR). Selected units received 20% v/v silicone oil and wereoperated as triphasic SBs (soil-aqueous phase-solvent). All activeSBs were bioaugmented with lindane-acclimated inocula from sus-pended growth seed bioreactors (methanogenic at day 0 and SR atday 15) (Camacho-Pérez, 2009).
Results: The M-SR SB without silicone oil showed the highest lin-dane removal efficiency 98% (Fig. 1). Yet, units added with siliconeoil exhibited a close removal (93%). The second (sulfate-reducing)stage of operation contributed the most to lindane reduction(Table 1). On average, ca. 41% of lindane was removed in the 15-d Mstage whereas the SR stage was responsable for 93% disappearanceof the pollutant. After 15 d operation pentachlorocyclohexene wasdetected in the slurry, whereas 1,2,4-trichlorobenzene was presentafter 30 d incubation (Fig. 2).
Discussion: Sequential M-SR operation of SB proved to performbetter than bioaugmented, only M and only SR SBs (removals of 41and 82%, respectively); the sequential process was also superior toSB operated as simultaneous M-SR that achieved just 65% lindanereduction (Robles-González, 2008). Sequential M-SR in our workalso showed higher lindane removals than triphasic sequential M-ASBs (58 to 82%, Camacho-Pérez et al., 2010).
Table 1Stage and overall lindane removal efficiencies in this experiment. Efficiencies are expressed in decimal numbers.
Treatment �1 (0 to 15 d) Methanogenic stage �2 (15 to 30 d) Sulfate-reducing stage �0 (30 d) Sequential M-SR
M-SR with no solvent 0.42 0.97 0.98M-SR with solvent at 20% v/v 0.40 0.89 0.93
Fig. 2. Mass spectra of: (a) pentachlorocyclohexene (m/z: 255); (b) 1,2,4-trichlorobenzene (m/z: 182) present in sequential methanogenic-sulfate reducing slurry bioreactorsafter (a) 15 and (b) 30 days of operation.
