Effect of inoculum type, packing material and operational conditions on the biofiltration of a mixture of hydrophobic volatile organic compounds in air

Paula Alejandra Lamprea Pineda; Kristof Demeestere; José Joaquín González-Cortés; Allan A Alvarado-Alvarado; Nico Boon; Frank Devlieghere; Herman Van Langenhove; Christophe Walgraeve

doi:10.1016/j.scitotenv.2023.167326

Effect of inoculum type, packing material and operational conditions on the biofiltration of a mixture of hydrophobic volatile organic compounds in air

Sci Total Environ. 2023 Dec 15:904:167326. doi: 10.1016/j.scitotenv.2023.167326. Epub 2023 Sep 23.

Authors

Paula Alejandra Lamprea Pineda¹, Kristof Demeestere², José Joaquín González-Cortés³, Allan A Alvarado-Alvarado⁴, Nico Boon⁵, Frank Devlieghere⁶, Herman Van Langenhove⁷, Christophe Walgraeve⁸

Affiliations

¹ Research group EnVOC, Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium. Electronic address: PaulaAlejandra.LampreaPineda@UGent.be.
² Research group EnVOC, Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium. Electronic address: Kristof.Demeestere@UGent.be.
³ Research group EnVOC, Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Department of Chemical Engineering and Food Technology, Vine and Agri-Food Research Institute (IVAGRO), University of Cadiz, Pol. Río San Pedro s/n, Puerto Real 11510, Cadiz, Spain. Electronic address: JoseJoaquin.GonzalezCortes@UGent.be.
⁴ Research group EnVOC, Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium. Electronic address: Allan.AlvaradoAlvarado@UAntwerpen.be.
⁵ Center for Microbial Ecology and Technology - CMET, Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium. Electronic address: Nico.Boon@UGent.be.
⁶ Research group FMFP, Department of Food Technology, Safety and Health, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium. Electronic address: Frank.Devlieghere@UGent.be.
⁷ Research group EnVOC, Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium. Electronic address: Herman.VanLangenhove@UGent.be.
⁸ Research group EnVOC, Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium. Electronic address: Christophe.Walgraeve@UGent.be.

PMID: 37748600
DOI: 10.1016/j.scitotenv.2023.167326

Abstract

The emission of volatile organic compounds (VOCs) into the atmosphere causes negative environmental and health effects. Biofiltration is known to be an efficient and cost-effective treatment technology for the removal of VOCs in waste gas streams. However, little is known on the removal of VOC mixtures and the effect of operational conditions, particularly for hydrophobic VOCs, and on the microbial populations governing the biofiltration process. In this study, we evaluated the effect of inoculum type (acclimated activated sludge (A-AS) versus Rhodococcus erythropolis) and packing material (mixture of compost and wood chips (C + WC) versus expanded perlite) on the removal of a mixture of hydrophobic VOCs (toluene, cyclohexane and hexane) in three biofilters (BFs), i.e., BF1: C + WC and R. erythropolis; BF2: C + WC and A-AS; and BF3: expanded perlite and R. erythropolis. The BFs were operated for 374 days at varying inlet loads (ILs) and empty bed residence times (EBRTs). The results showed that the VOCs were removed in the following order: toluene > cyclohexane > hexane, which corresponds to their air-water partitioning coefficient and thus bioavailability of each VOC. Toluene is the most hydrophilic VOC, while hexane is the most hydrophobic. BF2 outperformed BF1 and BF3 in each operational phase, with average maximum elimination capacities (ECmax) of 21 ± 3 g toluene m^-3 h^-1 (removal efficiency (RE): 100 %; EBRT: 82 s), 11 ± 2 g cyclohexane m^-3 h^-1 (RE: 86 ± 6 %; EBRT: 163 s) and 6.2 ± 0.9 g hexane m^-3 h^-1 (RE: 96 ± 4 %; EBRT: 245 s). Microbial analysis showed that despite having different inocula, the genera Rhodococcus, Mycobacterium and/or Pseudonocardia dominated in all BFs but at different relative abundances. This study provides new insights into the removal of difficult-to-degrade VOC mixtures with limited research to date on biofiltration.

Keywords: 16S rRNA gene amplicon sequencing; Cyclohexane; Hexane; SIFT-MS; Toluene.

MeSH terms

Air Pollutants* / analysis
Biodegradation, Environmental
Bioreactors / microbiology
Cyclohexanes
Filtration / methods
Hexanes
Toluene
Volatile Organic Compounds* / analysis

Substances

Volatile Organic Compounds
Perlite
n-hexane
Hexanes
Cyclohexane
Cyclohexanes
Toluene
Air Pollutants