title: Removal of diatrizoate with catalytically active membranes incorporating microbially produced palladium nanoparticles.
abstract: There is an increasing concern about the fate of iodinated contrast media (ICM) in the environment. Limited removal efficiencies of currently applied techniques such as advanced oxidation processes require more performant strategies. The aim of this study was to establish an innovative degradation process for diatrizoate, a highly recalcitrant ICM, by using biogenic Pd nanoparticles as free suspension or immobilized in polyvinylidene fluoride (PVDF) and polysulfone (PSf) membranes. As measured by HPLC-UV, the removal of 20mg L(-1) diatrizoate by a 10mg L(-1) Pd suspension was completed after 4h at a pH of 10. LC-MS analysis provided evidence for the sequential hydrodeiodination of diatrizoate. Pd did not lose its activity after incorporation in the PVDF and PSf matrix and the highest activity (k(cat)=30.0+/-0.4h(-1) L g(-1) Pd) was obtained with a casting solution of 10% PSf and 500mg L(-1) Pd. Subsequently, water containing 20mg L(-1) diatrizoate was treated in a membrane contactor, in which the water was supplied at one side of the membrane while hydrogen was provided at the other side. In a fed batch configuration, a removal efficiency of 77% after a time period of 48h was obtained. This work showed that membrane contactors with encapsulated biogenic nanoparticles can be instrumental for treatment of water contaminated with diatrizoate.
authors: Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, B-9000 Gent, Belgium.
authors: Tom
authors: T
authors: Hennebel
authors: Simon
authors: S
authors: De Corte
authors: Lynn
authors: L
authors: Vanhaecke
authors: Katrien
authors: K
authors: Vanherck
authors: Ilse
authors: I
authors: Forrez
authors: Bart
authors: B
authors: De Gusseme
authors: Pieter
authors: P
authors: Verhagen
authors: Kim
authors: K
authors: Verbeken
authors: Bart
authors: B
authors: Van der Bruggen
authors: Ivo
authors: I
authors: Vankelecom
authors: Nico
authors: N
authors: Boon
authors: Willy
authors: W
authors: Verstraete
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D003973:Diatrizoate / Q000302:isolation & purification*; D007700:Kinetics; D013058:Mass Spectrometry; D008567:Membranes, Artificial; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010165:Palladium / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D011145:Polyvinyls / Q000737:chemistry; D013052:Spectrometry, X-Ray Emission; D013450:Sulfones / Q000737:chemistry; D005465:Fluorocarbon Polymers
chemical_list: D003973:Diatrizoate; D008567:Membranes, Artificial; D010165:Palladium; D011108:Polymers; D011145:Polyvinyls; D013450:Sulfones; C024865:polyvinylidene fluoride; D005465:Fluorocarbon Polymers; C017662:polysulfone P 1700