title: Transport of Organic Compounds Through Porous Systems Containing Humic Acids.
abstract: Soil pollution by the presence of different contaminants (e.g. heavy metal ions or pesticides) is one of the biggest problems worldwide. The positive affinity of natural humic acids towards these contaminants might contribute to the soil and ground water protection; therefore it is necessary to study the reactivity and barrier properties of humic acids. An original reactivity-mapping tool based on diffusion techniques designed to study the reactivity and barrier properties of polyelectrolytes was developed and tested on humic acids. The results of diffusion experiments demonstrate that the electrostatic interactions between humic acids functioning as a polyelectrolyte interpenetrated in a supporting hydrogel matrix (agarose) and cationic dye (methylene blue) as a model solute have a crucial impact on the rate of diffusion processes and on the barrier properties of hydrogels. The intensity of interactions was evaluated by fundamental diffusion parameters (effective diffusion coefficients and breakthrough time). The impact of modification of humic acids was also studied by means of diffusion experiments conducted on two types of standard humic acids (Leonardite 1S104H) and humic acids with selectively methylated carboxylic groups.
authors.affiliation: Faculty of Chemistry, Materials Research Centre, Brno University of Technology, Purkynova 118/464, 612 00, Brno, Czech Republic. xcsmilek@fch.vutbr.cz.
authors.forename: Jiri
authors.initials: J
authors.lastname: Smilek
authors.affiliation: Faculty of Chemistry, Materials Research Centre, Brno University of Technology, Purkynova 118/464, 612 00, Brno, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Sedlacek
authors.affiliation: Faculty of Chemistry, Materials Research Centre, Brno University of Technology, Purkynova 118/464, 612 00, Brno, Czech Republic.
authors.forename: Marcela
authors.initials: M
authors.lastname: Lastuvkova
authors.affiliation: Faculty of Chemistry, Materials Research Centre, Brno University of Technology, Purkynova 118/464, 612 00, Brno, Czech Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Kalina
authors.affiliation: Faculty of Chemistry, Materials Research Centre, Brno University of Technology, Purkynova 118/464, 612 00, Brno, Czech Republic.
authors.forename: Martina
authors.initials: M
authors.lastname: Klucakova
mesh_terms: D004058:Diffusion; D006812:Humic Substances / Q000032:analysis*; D008751:Methylene Blue / Q000032:analysis*; D012685:Sepharose / Q000737:chemistry; D012987:Soil / Q000737:chemistry
chemical_list: D006812:Humic Substances; D012987:Soil; D012685:Sepharose; D008751:Methylene Blue
keywords: Diffusion; Humic acids; Hydrogel; Reactivity-mapping tool; Transport properties