title: Innovative slow-release organic carbon-source material for groundwater in situ denitrification.
abstract: Slow-release organic carbon-source (SOC) material, a new kind of electron donor for in situ groundwater denitrification, was prepared and evaluated in this study. With starch as a biologically utilized carbon source and polyvinyl alcohol (PVA) as a frame, this material performed controllable carbon release rates and demonstrated stable behaviour during the simulated denitrification process. Raman spectrum analysis showed that the PVA skeleton formed cross-linking network structures for hydrogen-bonded water molecules reset in low temperatures, and the starchy molecules filled in the interspace of the skeleton to form a two-phase interlocking/disperse phase structure. In a static system, carbon release processes followed the Fickian law with (1.294-6.560)×10(-3) mg g(-1) s(-1/2) as the release coefficient. Under domestication and in situ groundwater simulation conditions, SOC material played a favourable role during denitrification, with 1.049±0.165 as an average carbon-nitrogen ratio. The denitrification process followed the law of zero-order kinetics, while the dynamics parameter kN was 0.563-8.753 gN m(-3) d(-1). Generally, SOC material was suggested to be a potential carbon source (electron donor) suitable for in situ groundwater denitrification.
authors.affiliation: a Lancaster Environment Centre , Lancaster University , Lancaster LA1 4YQ , UK.
authors.forename: Dayi
authors.initials: D
authors.lastname: Zhang
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.forename: Yun
authors.initials: Y
authors.lastname: Wang
authors.forename: Guizhong
authors.initials: G
authors.lastname: Zhou
authors.forename: Guanghe
authors.initials: G
authors.lastname: Li
mesh_terms: D058440:Denitrification; D060587:Groundwater / Q000737:chemistry*; D009930:Organic Chemicals / Q000008:administration & dosage*
chemical_list: D009930:Organic Chemicals
keywords: denitrification; groundwater; polyvinyl alcohol (PVA); slow-release organic carbon-source; starch