The mobility of heavy metals in natural soil systems can be affected by the properties and compositions of those systems: the content and quality of organic matter as well as the character of inorganic constituents. In this work, the diffusion of copper(II) ions in humic hydrogels with incorporated calcium(II), magnesium(II), and iron(III) ions was investigated. The methods of instantaneous planar source and of constant source were used. Experimental data yielded the time development of the concentration in hydrogels and the values of effective diffusion coefficients. The coefficients include both the influence of the hydrogel structure and the interaction of diffusing particles with the hydrogel. Our results showed that the presence of natural metal ions such as calcium, magnesium, or iron can strongly affect the diffusivity of copper in humic systems. They indicate that the mobility of copper ions depends on their concentration. The mobility can be supported by higher contents of copper in the system. While the incorporation of Ca and Mg resulted in the decrease in the diffusivity of copper ions, the incorporation of Fe(III) into humic hydrogel resulted in an increase in the diffusivity of Cu(II) in the hydrogel in comparison with pure humic hydrogel.

Brno University of Technology Faculty of Chemistry Purkyňova 118 612 00 Brno Czech Republic

See more in PubMed

Bryan ND, Barlow J, Warwick P, Stephens S, Higg JJW, Griffin D (2005) The simultaneous modelling of metal ion and humic substance transport in column experiments. J Environ Monit 7:196–202. 10.1039/B413241F 10.1039/B413241F PubMed DOI

Chen W, Habibul N, Liu X-Y, Sheng G-P, Yu H-Q (2015) FTIR and synchronous fluorescence heterospectral two-dimensional correlation analyses on the binding characteristics of copper onto dissolved organic matter. Environ Sci Technol 49:2052–2058. 10.1021/es5049495 10.1021/es5049495 PubMed DOI

Christl I, Milne CJ, Kinniburgh DG, Kretzschmar R (2001) Relating ion binding by fulvic and humic acids to chemical composition and molecular size. 2. Metal Binding Environ Sci Technol 35:2512–2517. 10.1021/es0002520 10.1021/es0002520 PubMed DOI

Christl I, Metzger A, Heidmann I, Kretzschmar R (2005) Effect of humic and fulvic acid concentrations and ionic strength on copper and lead binding. Environ Sci Technol 39:5319–5326. 10.1021/es050018f 10.1021/es050018f PubMed DOI

Conte P, Piccolo A (1999) Conformational arrangement of dissolved humic substances. Influence of solution composition on association of humic molecules. Environ Sci Technol 33:1682–1690. 10.1021/es980860410.1021/es9808604 DOI

De Nobili M, Bragato G, Alcaniz JM, Puigbo A, Comellas L (1990) Characterization of electrophoretic fractions of humic substances with different electrofocusing behavior. Soil Sci 150:763–770. 10.1097/00010694-199011000-0000210.1097/00010694-199011000-00002 DOI

Ding Y, Liu M, Peng S, Li J, Liang Y, Shi Z (2019) Binding characteristics of heavy metals to humic acid before and after fractionation by ferrihydrite. Chemosphere 226:140–148. 10.1016/j.chemosphere.2019.03.124 10.1016/j.chemosphere.2019.03.124 PubMed DOI

Dinu MI (2015) Interaction between metal ions in waters with humic acids in gley-podzolic soils. Geochem Int 53”265–276. 10.1134/S0016702915030052

Evangelou VP, Marsi M (2001) Composition and metal ion complexation behaviour of humic fractions derived from corn tissue. Plant Soil 229:13–24. 10.1023/A:100486210092510.1023/A:1004862100925 DOI

Farina AO, Peacock CL, Fiol S, Antelo J, Carvin B (2018) A universal adsorption behaviour for Cu uptake by iron (hydr)oxide organo-mineral composites. Chem Geol 479:23–35. 10.1016/j.chemgeo.2017.12.02210.1016/j.chemgeo.2017.12.022 DOI

Francioso O, Ciavatta C, Tugnoli V, Sanchez-Cortes S, Gessa C (1998) Spectroscopic characterization of pyrophosphate incorporation during extraction of peat humic acids. Soil Sci Soc Am J 62:181–187. 10.2136/sssaj1998.03615995006200010024x10.2136/sssaj1998.03615995006200010024x DOI

Gao Y, Yan M, Korshin G (2015) Effects of calcium on the chromophores of dissolved organic matter and their interactions with copper. Water Res 81:47–53. 10.1016/j.watres.2015.05.038 10.1016/j.watres.2015.05.038 PubMed DOI

Gerzabek M, Pichlmayer F, Kirchmann H, Haberhauer G (1997) The response of soil organic matter to manure amendments in a long-term experiment at Ultuna, Sweden. Eur J Soil Sci 48:273–282. 10.1111/j.1365-2389.1997.tb00547.x10.1111/j.1365-2389.1997.tb00547.x DOI

Haberhauer G, Gerzabek MH (1999) Drift and transmission FT-IR spectroscopy of forest soils: an approach to determine decomposition processes of forest litter. Vibr Spectr 19:413–417. 10.1016/S0924-2031(98)00046-010.1016/S0924-2031(98)00046-0 DOI

Hamilton-Taylor J, Postill AS, Tipping E, Harper MP (2002) Laboratory measurements and modeling of metal-humic interactions under estuarine conditions. Geochim Cosmochim Acta 66:403–415. 10.1016/S0016-7037(01)00777-310.1016/S0016-7037(01)00777-3 DOI

Hayes TM, Hayes MHB, Skjemstad JO, Swift RS (2008) Compositional relationships between organic matter in a grassland soil and its drainage waters. Eur J Soil Sci 59:603–616. 10.1111/j.1365-2389.2007.01007.x10.1111/j.1365-2389.2007.01007.x DOI

Hayes TM, Hayes MH, Swift RS (2012) Detailed investigation of organic matter components in extracts and drainage waters from a soil under long term cultivation. Org Geochem 52:13–22. 10.1016/j.orggeochem.2012.07.01110.1016/j.orggeochem.2012.07.011 DOI

Haynes WM (2012) Handbook of chemistry and physics, 93rd edn. CRC Press, Boca Raton

Head MJ, Zhou WJ (2000) Evaluation of NaOH leaching techniques to extract humic acids from paleosols. Nucl Instr Meth Phys Res B 172:434–439. 10.1016/S0168-583X(00)00221-410.1016/S0168-583X(00)00221-4 DOI

Kang F, Hamilton PB, Long J, Wang Q (2010) Influence of calcium precipitation on copper sorption induced by loosely bound extracellular polymeric substance (LB-EPS) from activated sludge. Fundam Appl Limnol Arch Hydrobiol 176:173–181. 10.1127/1863-9135/2010/0176-017310.1127/1863-9135/2010/0176-0173 DOI

Klučáková M (2014) Complexation of metal ions with solid humic acids, humic colloidal solutions, and humic hydrogel. Environ Eng Sci 31:612–620. 10.1089/ees.2013.048710.1089/ees.2013.0487 DOI

Klučáková M (2022) The effect of supramolecular humic acids on the diffusivity of metal ions in agarose hydrogel. Molecules 27:1019. 10.3390/molecules27031019 10.3390/molecules27031019 PubMed DOI PMC

Klučáková M, Kalina M (2015) Diffusivity of Cu(II) ions in humic gels - influence of reactive functional groups of humic acids. Colloid Surface A 483:162–170. 10.1016/j.colsurfa.2015.05.04110.1016/j.colsurfa.2015.05.041 DOI

Klučáková M, Pekař M (2003a) Study of structure and properties of humic and fulvic acids. III. Study of complexation of Cu2+ ions with humic acid in sols. J Polym Mater 20:145–154

Klučáková M, Pekař M (2003b) Study of structure and properties of humic and fulvic acids. IV. Study of interactions of Cu2+ ions with humic gels and final comparison. J Polym Mater 20:155–162

Klučáková M, Pekař M (2004) Study of diffusion of metal cations in humic gels. In: Ghabbour EA, Davies G (eds) Humic substances: Nature`s most versatile materials. Taylor & Francis, New York, pp 263–273

Klučáková M, Pekař M (2009) Transport of copper(II) ions in humic gel – new results from diffusion couple. Colloid Surface A 349:96–101. 10.1016/j.colsurfa.2009.08.00110.1016/j.colsurfa.2009.08.001 DOI

Klučáková M, Kalina M, Sedláček P, Grasset L (2014) Reactivity and transport mapping of Cu(II) ions in humic hydrogels. J Soil Sediment 14:368–376. 10.1007/s11368-013-0730-210.1007/s11368-013-0730-2 DOI

Kogut M, Voelker B (2001) Strong copper-binding behavior of terrestrial humic substances in seawater. Environ Sci Technol 35:1149–1156. 10.1021/es0014584 10.1021/es0014584 PubMed DOI

Lippold H, Evans NDM, Warwick P, Kupsch H (2007) Competitive effect of iron(III) on metal complexation by humic substances: characterisation of ageing processes. Chemosphere 67:1050–1056. 10.1016/j.chemosphere.2006.10.045 10.1016/j.chemosphere.2006.10.045 PubMed DOI

Maia CMBF, Piccolo A, Mangrich AS (2008) Molecular size distribution of compost-derived humates as a function of concentration and different counterions. Chemosphere 73:1162–1166. 10.1016/j.chemosphere.2008.07.069 10.1016/j.chemosphere.2008.07.069 PubMed DOI

Martyniuk H, Więckowska J (2003) Adsorption of metal ions on humic acids extracted from brown coals. Fuel Process Technol 84:23–36. 10.1016/S0378-3820(02)00246-110.1016/S0378-3820(02)00246-1 DOI

Monk P (2004) Physical chemistry. Understanding our chemical world, first ed, John Wiley & Sons Ltd, Chichester

Muller FLL, Cuscov M (2017) Alteration of the copper-binding capacity of iron-rich humic colloids during transport from peatland to marine waters. Environ Sci Technol 51:3214–3222. 10.1021/acs.est.6b05303 10.1021/acs.est.6b05303 PubMed DOI

Novotny EH, Blum WEH, Gerzabek MH, Mangrich AS (1999) Soil management system effects on size fractionated humic substances. Geoderma 92:87–109. 10.1016/S0016-7061(99)00022-110.1016/S0016-7061(99)00022-1 DOI

Nuzzo A, Sanchez A, Fontaine B, Piccolo A (2013) Conformational changes of dissolved humic and fulvic superstructures with progressive iron complexation. J Geochem Explor 129:1–5. 10.1016/j.gexplo.2013.01.01010.1016/j.gexplo.2013.01.010 DOI

Paradelo M, Perez-Rodriguez P, Fernandez-Calvino D, Arias-Estevez M, Lopez-Periago JE (2012) Coupled transport of humic acids and copper through saturated porous media. Eur J Soil Sci 63:708–716. 10.1111/j.1365-2389.2012.01481.x10.1111/j.1365-2389.2012.01481.x DOI

Peuravuori J, Žbánková P, Pihlaja K (2006) Aspects of structural features in lignite and lignite humic acids. Fuel Process Technol 87:829–839. 10.1016/j.fuproc.2006.05.00310.1016/j.fuproc.2006.05.003 DOI

Peuravuori J, Simpson AJ, Lam B, Žbánková P, Pihlaja K (2007) Structural features of lignite humic acid in light of NMR and thermal degradation experiments. J Mol Struct 826:131–142. 10.1016/j.molstruc.2006.04.04810.1016/j.molstruc.2006.04.048 DOI

Rey-Castro C, Mongin S, Huidobro C, David C, Salvador J, Garcés JL, Galceran J, Mas F, Puy J (2009) Effective affinity distribution for the binding of metal ions to a generic fulvic acid in natural waters. Environ Sci Technol 43:7184–7191. 10.1021/es803006p 10.1021/es803006p PubMed DOI

Rosa HA, Oliveira LC, Bellin IC, Rocha JC, Romão LPC, Filho NLD (2005) Influence of alkaline extraction on the characteristics of humic substances in Brasilian soils. Thermochim Acta 433:81–86. 10.1016/j.tca.2005.02.00110.1016/j.tca.2005.02.001 DOI

Saito T, Koopal LK, Nagasaki S, Tanaka S (2005) Analysis of copper binding in the ternary system Cu2+/humic acid/goethite at neutral to acidic pH. Environ Sci Technol 39:4886–4893. 10.1021/es0500308 10.1021/es0500308 PubMed DOI

Scally S, Davison W, Zhang H (2006) Diffusion coefficients of metals and metal complexes in hydrogels used in diffusive gradients in thin films. Anal Chim Acta 558:222–229. 10.1016/j.aca.2005.11.02010.1016/j.aca.2005.11.020 DOI

Shi Z, Wang P, Peng L, Lin Z, Dang Z (2016) Kinetics of heavy metal dissociation from natural organic matter: roles of the carboxylic and phenolic sites. Environ Sci Technol 50:10476–10484. 10.1021/acs.est.6b01809 10.1021/acs.est.6b01809 PubMed DOI

Sowers TD, Adhikari D, Wang J, Yang Y, Sparks DL (2018) Spatial associations and chemical composition of organic carbon sequestered in Fe, Ca, and organic carbon ternary systems. Environ Sci Technol 52:6936–6944. 10.1021/acs.est.8b01158 10.1021/acs.est.8b01158 PubMed DOI

Sureshkumar MK, Das D, Mary G, Nuwad J (2013) Adsorption of Pb(II) ions using humic acid coated chitosan-tripolyphosphate (HA-CTPP) beads. Sep Sci Technol 48:1132–1139. 10.1080/01496395.2012.72450010.1080/01496395.2012.724500 DOI

Tatzber M, Stemmer M, Spiegel H, Katzlberger C, Haberhauer G, Mentler A, Gerzabek MH (2007) FTIR-spectroscopic characterization of humic acids and humin fractions obtained by advanced NaOH, Na4P2O7, and Na2CO3 extraction procedures. J Plant Nutr Soil Sci 170:522–529. 10.1002/jpln.20062208210.1002/jpln.200622082 DOI

Thurman EM, Malcolm RL (1981) Preparative isolation of aquatic humic substances. Environ Sci Technol 15:463–466. 10.1021/es00086a012 10.1021/es00086a012 PubMed DOI

Tipping E, Vincent CD, Lawlor AJ, Lofts S (2008) Metal accumulation by stream bryophytes, related to chemical speciation. Environ Pollut 156:936–943. 10.1016/j.envpol.2008.05.010 10.1016/j.envpol.2008.05.010 PubMed DOI

van Oort F, Monna F, Garnier S (2020) Zn/Pb concentration ratios emphasize spatiotemporal airborne metal dynamics in soils under different land use. Water Air Soil Pollut 231:109. 10.1007/s11270-020-04478-110.1007/s11270-020-04478-1 DOI

Watanabe, Kuwatsuka S (1991) Fractionation of soil fulvic acids using polyvinyl-pyrrolidone and their ionization difference spectra. Soil Sci Plant Nutr 37:611–617. 10.1080/00380768.1991.1041692910.1080/00380768.1991.10416929 DOI

Wieckowska J, Martyniuk H (2003) Adsorption of metal ions on humic acids extracted from brown coals. Fuel Process Technol 84:23–36. 10.1016/S0378-3820(02)00246-110.1016/S0378-3820(02)00246-1 DOI

Wu Y, Hendershot WH (2010) Effect of calcium and pH on copper binding and rhizotoxicity to pea (Pisum sativum L.) root: Empirical relationships and modeling. Arch Environ Contam Toxicol 59:109–119. 10.1007/s00244-009-9450-4 10.1007/s00244-009-9450-4 PubMed DOI

Zhang H, Davison W (1999) Diffusional characteristics of hydrogels used in DGT and DET techniques. Anal Chim Acta 398:329–340. 10.1016/S0003-2670(99)00458-410.1016/S0003-2670(99)00458-4 DOI