Valencia, 26-29. September, 2016 Evaluation of solid-phase chromatography as a method for natural organic matter characterization Dr Aleksandra Tubić, Dr Jasmina Agbaba, Dr Jelena Molnar Jazić, Dr Božo Dalmacija Department of Chemistry, Biochemistry and Environmental Protection Faculty of Science, University of Novi Sad, R. Serbia

Overview Relevance of NOM in drinking water resource and treatment Valencia, 26-29. September, 2016 Overview Relevance of NOM in drinking water resource and treatment Methods for NOM characterisation Solid phase extraction as a tool for NOM characterisation Conclusion

What is NOM? Complex mixture of organic compouns Acid Base Neutral Valencia, 26-29. September, 2016 What is NOM? Complex mixture of organic compouns H Y D R O F I L C Acid Base Neutral Aliphatic structures Carbohydrates Proteins Sugars Aminoacids B IC Aromatic structures Phenol structures Structures whit conugated doble bonds

Hypothetical structures Natural organic matter (NOM) found has extreme mixture and molecular structural complexity Valencia, 26-29. September, 2016 Attempts to determine molecular structural components of NOM into pure compounds required for structural analyses have not yet been successful. Hypothetical structures (Schulten, 1999, J.Analytical Applyed Pyrolysis 49, 385-415)

NOM Local issue in Serbia As NOM NOM-As interactions Valencia, 26-29. September, 2016 NOM Microbial growth in distribution system DBP formation Influence on other constituents behaviour Increase in chemical demand during treatment Influence on organoleptic characteristics of water Local issue in Serbia NOM-As interactions NOM As

Characterisation of NOM? Valencia, 26-29. September, 2016 Leenhee, 1981; Marhaba et al., 2003 Matilainen, 2010; Amy, 2011 Fractionation NOM alteration Filtration XAD-8 resin Hydrophobic bases and neutrals Week hydrophobic acids Cation exchange resin Hydrophylic bases Anion exchange resin Hydrophylic acids Hydrophylic neutrals left in water Protocol for characterisation without NOM alteration HPSEC FTIR NMR LC-OCD-OND F-EEM TEP Get knowledge and separate on MW Humic/fulvic like structures Protein like structures hydrophilic surface active acid polysaharides Comparison of efforts nowdays and 30 years ago- how we see them?

Solubility based fractionation Valencia, 26-29. September, 2016 Raw water cc HCL, pH 2 0.1 N NaOH cc HCl pH 1 Precipitate Dissolution in 0.1N NaOH 0.45 µm membrane filter Molnar, 2011

XAD-8 – hydrofobic fractions fulvic acid fraction - FAF Valencia, 26-29. September, 2016 Developed in 1981. (Leenheer, 1981, Environmental Science and Technology, 15(5), 578-587) Standard method for isolation of humic and fulvic acids – International Humic Substance Society XAD-8 – hydrofobic fractions fulvic acid fraction - FAF humic acid fraction - HAF XAD-4 – hydrophilic fractions week hydrophilic acid fraction - HPIA hydrophilic non-acid fraction – HPI-NA Hydrophilic fraction further fractionation (Marhaba i sar., 2003, J.Hazard. Mater. B101,43-54) AG-MP-50 – cation resin WA-10 – week anion resin

Disadvantages of the method? Valencia, 26-29. September, 2016 Disadvantages of the method? Possible: change of chemical/physical structure of NOM due to extreme pH irreversible adsorption of NOM molecules on resins contamination by leaking from the resin exclusion effect

DOC Recovery Bulk water After fractionation 10.2 mg C/L 10.1 mg C/L Valencia, 26-29. September, 2016 DOC Recovery Bulk water 10.2 mg C/L After fractionation 10.1 mg C/L Higher than 98% Fraction Fraction ratio % of total DOC Average SD RSD x1 x2 x3 HAF 14.0 15.5 13.0 14.2 1.26 8.9 FAF 68.0 66.5 67.8 67.4 0.81 1.2 HPINA 12.0 13 1 7.7 HPIA 6.0 5.0 5.2 5.4 0.53 9.9

Recovery after resin regeneration I cycle – 99% Valencia, 26-29. September, 2016 Recovery after resin regeneration II cycle – 97% III cycle – 88%

Groundwater of Vojvodina region, Republic of Serbia Valencia, 26-29. September, 2016 Example from my collegues related to our groundwater characterisation Molnar et al. (2012) Environmental Science and Pollution Research, 19, 3079-3086. Tubić et al. (2013) Journal of Environmental Management, 118, 153-163 Agbaba et al. (2015) Water Science & Technology: Water Supply, 15(1), 75-83.

Thank you for your attention Valencia, 26-29. September, 2016 Authors Thank you for your attention Aleksandra Tubić Assistant professor Jasmina Agbaba Full professor Jelena Molnar Božo Dalmacija