title: Remediation of trichloroethylene by bio-precipitated and encapsulated palladium nanoparticles in a fixed bed reactor.
abstract: Trichloroethylene is a toxic and recalcitrant groundwater pollutant. Palladium nanoparticles bio-precipitated on Shewanella oneidensis were encapsulated in polyurethane, polyacrylamide, alginate, silica or coated on zeolites. The reactivity of these bio-Pd beads and zeolites was tested in batch experiments and trichloroethylene dechlorination followed first order reaction kinetics. The calculated k-values of the encapsulated catalysts were a factor of six lower compared to non-encapsulated bio-Pd. Bio-Pd, used as a catalyst, was able to dechlorinate 100 mgL(-1) trichloroethylene within a time period of 1h. The main reaction product was ethane; yet small levels of chlorinated intermediates were detected. Subsequently polyurethane cubes empowered with bio-Pd were implemented in a fixed bed reactor for the treatment of water containing trichloroethylene. The influent recycle configuration resulted in a cumulative removal of 98% after 22 h. The same reactor in a flow through configuration achieved removal rates up to 1059 mg trichloroethylene g Pd(-1)d(-1). This work showed that fixed bed reactors with bio-Pd polyurethane cubes can be instrumental for remediation of water contaminated with trichloroethylene.
authors: Laboratory of Microbial Ecology and Technology, Ghent University, Coupure Links 653, B-9000 Gent, Belgium.
authors: Tom
authors: T
authors: Hennebel
authors: Pieter
authors: P
authors: Verhagen
authors: Henri
authors: H
authors: Simoen
authors: Bart
authors: B
authors: De Gusseme
authors: Siegfried E
authors: SE
authors: Vlaeminck
authors: Nico
authors: N
authors: Boon
authors: Willy
authors: W
authors: Verstraete
mesh_terms: D001673:Biodegradation, Environmental; D019149:Bioreactors; D002384:Catalysis; D007700:Kinetics; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000382:microbiology; D010165:Palladium / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D020592:Shewanella / Q000378:metabolism; D014241:Trichloroethylene / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D011108:Polymers; D014874:Water Pollutants, Chemical; D014241:Trichloroethylene; D010165:Palladium