4 th IWA Specialist Conference Natural Organic Matter: from Source to Tap 2-4 th September, 2008 Bath, UK. using informative parameters

Transcription

1 4 th IWA Specialist Conference Natural Organic Matter: from Source to Tap 2-4 th September, 2008 Bath, UK Characterizing natural organic matters using informative parameters Kangmin Chon, Jaeweon Cho Gwangju Institute t of Science and Technology (GIST)

2 Outline Introduction Problematics / Motivation Objectives Materials and Methods Sample preparation Analytical methods Results and Discussion Water characteristics Total nitrogen (TN) and organic nitrogen (org-n) measurement High-performance size-exclusion exclusion chromatography (HPSEC) 3D fluorescence excitation-emission matrix (EEM) Fourier transform infrared spectroscopy (FTIR) NOM fractionation using XAD 8/4 resins Summaries Application to environmental samples Conclusions 2 / 29

3 Introduction Problematics / Motivation Objectives

4 Problematics / Motivation Problematics of NOM Disinfection by-products (DBPs) Flux decline The previous research on NOM NOM characterization (Barrett, ACS Symposium Series, 2000) NOM removal in membrane filtration system (Braghetta, J. Environ. Eng., 1997) The recent research on NOM The origin, chemical interaction, transport mechanism, and biological availability of NOM (Leenheer, Humics and Soils, 1991) 4 / 29

5 Problematics / Motivation The chemical characterization of NOM should be performed. To better understand the biochemical cycles Informative parameters were developed d to characterize the NOM. Water source, characteristics, and water Informative parameters Quick and easy tool to characterize NOM 5 / 29

6 Objectives To characterize the NOM using informative parameters. To characterize various types of NOM with respect to the source. To compare the physical and chemical characteristics s of NOM To evaluate and predict the water quality using informative parameters 6 / 29

7 Materials and Methods Sample preparation p Analytical methods

8 Sample preparation p Four different types of NOM Autochthonous NOM Algogenic g organic matter (AOM) Bacterial organic matter (BOM) Allochthonous NOM Humic acid Fulvic acid Microcystis Flavobacterium Suwannee River Suwannee River aeruginosa lutescens humic acid (SRHA) fulvic acid (SRFA) (NIER, Korea) (KCTC, Korea) (IHSS, USA) IHSS, USA) Sample preparation Filtration with 0.45 μm filter Subcultured algae and bacteria Centrifugation at 7000 rpm SMPs were extracted by for 10 min to remove sonication for 20 min the liquid medium using DI water SMPs: soluble microbial products 8 / 29

9 Analytical methods Categories Methods Details DOC analysis TOC measurement 800 TOC analyzer, Sievers UV absorbance UVA at 254 nm UV-1601, Shimadzu TN and Org-N measurement MW distribution and averaged-mw Major component and complexity TN measurement TOC-V CPH equipped with TNM-1, Shimadzu Ion chromatography High performance sizeexclusion chromatography (HP-SEC) 3D fluorescence excitation-emission matrix (EEM) ICS-90/DX-120, Dionex Column: Protein pak 125, Waters UV/Vis detector: SPD-10A VP, Shimadzu Fluorescence detector: RF-10A XL, Shimadzu F-2500 fluorescence spectrophotometer equipped with xenon lamp, Hitachi Specific functional Fourier Transformation FT/IR-460 plus FTIR, Jasco Groups Infrared NOM structure NOM fractionation XAD 8/4 resins, Amberlite TN: Total nitrogen, Org-N: Organic nitrogen, MW: Molecular weight 9 / 29

10 Results and Discussion Water characteristics TN and Org-N measurement High-performance size-exclusion chromatography 3D fluorescence excitation-emission matrix Fourier transform infrared spectroscopy NOM fractionation using XAD 8/4 resins Summary

11 Water characteristics Water characteristics of NOM ph Conductivity DOC SUVA UVA (μs/cm) 254 (mgc/l) (L m -1 mg -1 ) AOM BOM SRHA SRFA SRHA and SRFA were mainly comprised of aromatic compounds. 11 / 29

12 TN and org-n measurement Calculation of organic nitrogen concentration Org-N = TN Total inorg-n (Nitrite, Nitrate, and Ammonia) Nitrogen properties of NOM TN Inorganic nitrogen (mg/l) org-n org-n/c (mg/l) Total Nitrite Nirate Ammonia (mgn/l) (molar) AOM BOM SRHA SRFA org-n: organic nitrogen concentration as nitrogen TN: total nitrogen concentration, Total inorg-n: total inorganic nitrogen concentration AOM and BOM exhibited relatively higher microbial activity than the SRHA and SRFA. 12 / 29

13 High-performance size-exclusion chromatography MW distribution of aromatic substances 3,550 1, nm (mv) UV response ( AOM BOM SRHA SRFA nm Molecular weight (Da) SRHA and SRFA included d more relatively l large characteristic MW than AOM and BOM. 13 / 29

14 High-performance size-exclusion chromatography MW distribution of protein-like substances Ex = 278 nm Em = 353 nm 3,550 58,360 1, nm 41, , , AOM and BOM consisted of a wide range of MW compared with SRHA and SRFA. 14 / 29

15 High-performance size-exclusion chromatography Averaged-MW and polydispersity measured by UVA Averaged-MW and polydispersity measured by fluorescence detector Numberaveraged MW (Mn) Weightaveraged MW (Mw) Polydispersity (Mw/Mn) Numberaveraged MW (Mn) Weightaveraged MW (Mw) Polydispersity (Mw/Mn) AOM AOM BOM BOM SRHA SRHA SRFA SRFA Protein-like compounds of BOM can be easily degraded by microorganisms. 15 / 29

16 3D fluorescence excitation-emission matrix Fluorescence contour maps of different NOMs: (a) AOM, (b) BOM, (c) SRHA, and (d) SRFA Protein-like (Coble, Marine Chemistry, 1996) at Ex= nm and Em= nm Humic-like (Coble, Marine Chemistry, 1996) at Ex= nm and Em= nm, Ex= nm and Em= nm (a) (b) (c) (d) 16 / 29

17 3D fluorescence excitation emission matrix Maximum peak and corresponding compounds of NOM Maximum peak location Excitation (nm) Emission (nm) Compounds type AOM Protein-like BOM Protein-like SRHA Humic-like Humic-like SRFA Humic-like Humic-like AOM and BOM could present relatively l hydrophilic hili characteristics. ti 17 / 29

18 Fourier transform infrared spectroscopy Absorbance SRHA N-H Amines 2930 O-H Carboxylic acid CH Aldehydes C=O Aldehydes d 2350 P-H Phosphorus C=O Aldehydes AOM BOM SRHA SRFA 1230 C-O Alcohols CNH Amides C-N Amides 1350 CH 3 N acetyl groups of amino sugar CNH amides C-O alcohols FTIR spectra of four different types of NOM SRHA.0 Autochthonous NOM and allochthonous NOM additionally included BOM different functional groups. 0.5 AOM Wavenumber (cm -1 ) /

19 NOM fractionation using XAD 8/4 resins Structural analysis results of four different types of NOM NOM fractions (%) HPO fraction HPI fraction TPI fraction AOM BOM SRHA SRFA HPO: Hydrophobic, HPI: Hydrophilic, TPI: Transphilic Hydrophilic fraction of BOM was about four times as high h as those of SRHA and SRFA. 19 / 29

20 Summaries Hydrophilic characteristics, ti in terms of SUVA, major components and hydrophilic fractions AOM and BOM > SRHA and SRFA Microbial activity, in terms of org-n/c molar ratio AOM and BOM > SRHA and SRFA High utilization of NOM by microorganisms Protein-like substances of BOM Water quality might be easily evaluated and predicted by the informative parameters. 20 / 29

21 Application to environmental samples Three different types of environmental samples 1. Wetland (NOM, Acrous): Damyang constructed wetland, Korea 2. Wetland (NOM, Typha): Damyang constructed wetland, Korea 3. Eutrophicated lake (AOM, Dongbok): Dongbok reservoir, Korea

22 Relationship between SUVA and org-n/c 8.0 Allochthonous NOM SRHA 6.0 SUVA (L m-1 mg-1) SRFA Wetland (Acrous) Wetland (Typha) Autochthonous NOM 2.0 AOM BOM Eutrophicated lake (Donbok) Molar ratio of org-n/c Environmental samples exhibited different trends of SUVA and org-n/c molar ratio. 22 / 29

23 High-performance size-exclusion chromatography 3, nm Ex = 278 nm, Em = 353 nm 1, ,360 41, ,070 12,270 UV resp ponse (mv) Wetland (Acorus) Wetland (Typha) Eutrophicated p lake (Dongbok) 1, ,150 Fluorescence e response (mv V) nm Ex = 278 nm Em = 353 nm Wetland (Acorus) Wetland (Typha) Eutrophicated lake (Dongbok) 36, e+0 1e+1 1e+2 1e+3 1e+4 1e+5 1e+6 Molecular weight (Da) 0 1e-1 1e+0 1e+1 1e+2 1e+3 1e+4 1e+5 1e+6 1e+7 Molecular weight (Da) Environmental samples were comprised of slightly small characteristic MW. 23 / 29

24 3D fluorescence excitation-emission matrix 340 Wetland (Typha) 310 Protein-like Wetland (Acorus) Peak II of SRFA Peak II of SRHA Excitatio ion (nm) 280 AOM BOM Eutrophicated lake (Dongbok) Humic-like Peak I of SRHA Peak I of SRFA Emission (nm) Eutrophicated lake corresponds to the protein-like form while wetland samples correspond to the humic-like form. 24 / 29

25 Fourier transform infrared spectroscopy Absorbance N-H Amines O-H Carboxylic acids CH Aldehydes Eutrophicated lake (Dongbok) Wetland (Acorus) Wetland (Typha) Eutrophicated lake (Dongbok) C=O Aldehydes OH Alcohols P-H Phophorus C-N Amines C-O Alcohols O-H Carboxylic acids NH Amines sorbance Abs SRHA SRHA BOM N-H Amines 2930 O-H Carboxylic acid CH Aldehydes C=O Aldehydes 2350 P-H Phosphorus C=O Aldehydes AOM BOM SRHA SRFA 1230 C-O Alcohols CNH Amides C-N Amides 1350 CH 3 N acetyl groups of amino sugar CNH amides C-O alcohols 0.5 AOM 0.5 Wetland (Typha) Wavenumber (cm -1 ) Wetland (Acorus) Amines, carboxylic acids, aldehydes and alcohols were common functional groups Wavernumber (cm -1 ) /

26 NOM fractionation using XAD 8/4 resins 100 Hydrophobic hydrophilic transphilic 80 Fractions (%) AOM BOM SRHA SRFA Wetland (Acrous) Wetland (Typha) Eutrophicated lake (Dongbok) Hydrophilic factions of all environmental samples were similar to autochthonous NOM. 26 / 29

27 Conclusions

28 Conclusions Different trends of SUVA and org-n/c molar ratio Complexity of their origins Higher hydrophilic fractions Major component: protein-like form Informative parameters gave us a potential way To characterize NOM To characterize NOM [On-going g research] 1. Comparison of pyrochromatograms and 3D fluorescence EMM 2. Molecular identification of NOM structures 28 / 29

29 Acknowledgements This research was supported by National Research Laboratory from the Korea Science and Engineering Foundation and basic research project of GIST. Thank you for Presenter: your attention! Advisor: 29 / 29 t tl