Updated: 1 December 2013 CEE697K Lecture #21 1 Print version CEE 697K ENVIRONMENTAL REACTION KINETICS Lecture #21 Case Study: NOM-oxidant kinetics Primary Literature as noted Introduction
Kinetic Spectrum Analysis 2 For mixtures of many closely related compounds A new continuum of rate constants E.g., NOM n ∑ Kinetic: Shuman model − = k t [ C ] [ C ] e i t i 0 = Equilibria: Perdue model i 1 Very general, but highly subject to errors CEE697K Lecture #21
Factors affecting DBP levels 3 Raw water NOM levels (e.g., TOC) Specific precursor content of the RW NOM NOM removal Disinfection regime type & dose location in plant contact time & temp pH Degradation in DS (affects some) CEE697K Lecture #21
NOM Origins 4 Upper Soil Horizon Lower Soil Horizon Litter Layer Lake Algae Aquifer Sediment & Gravel in Lake Bed CEE697K Lecture #21
Practical Management Question: Which is the more important source? 5 or allochthonous autochthonous CEE697K Lecture #21
An Aquatic Humic “Structure” 6 Hydroxy Acid OH COOH From Thurman, 1985 HO COOH COOH Aliphatic HOOC Dicarboxylic Phenolic-OH Acid O OH HOOC HO Aromatic Aliphatic Acid Dicarboxylic Acid H 3 CO COOH COOH Aromatic CEE697K Lecture #21 Acid
Chorine + Aromatics 7 Chlorination of Resorcinol From Boyce & Hornig, 1983 All structures identified by GC/MS except those in brackets CEE697K Lecture #21
Aliphatics: Haloform Reaction 8 RLS is deprotonation (k 1 ) under many conditions H+ - - O O O [ ] C H 3 C C H 3 C H 3 C C H 2 C H 3 C C H 2 Many LFERs exist HO C l for estimating K a s H - E.g., Perrin et al., 1982 O O O O HO C l HO C l Then relate C H 3 C C H 2C l C H 3 C C H C l 2 C H 3 C C C l 3 H 2 O k 1 to K a H 2 O - O H - O O O O - C H 3 C C C l 3 C H 3 C O H C H 3 C O H CEE697K Lecture #21 - C C l 3 C H C l 3
An Aquatic Humic “Structure” 9 Hydroxy Acid OH COOH From Thurman, 1985 HO COOH COOH Aliphatic HOOC Dicarboxylic Phenolic-OH Acid O OH HOOC HO Aromatic Aliphatic Acid Dicarboxylic Acid H 3 CO COOH COOH Aromatic CEE697K Lecture #21 Acid
HPL= Hydrophi l ic NOM Fractions: HPO= Hydroph o bic Mass Balance A= Acids W= Weak B= Bases 10 u= ultra HA N= Neutrals 8% HPL-N 25% HA HPL-A 0% HPL-B 15% 3% FA FA 29% HPL-A 42% 9% HPL-N 11% HPO-N 7% HPO-B HPL-B W-HPO-A 2% 5% 4% Northeast MA W-HPO- 16% Tap Water Forge Pond uHPL-A HPO-B Granby, MA 22% HPO-N 0% 10 CEE697K Lecture #21 2%
10 Absorbance Humic Acid 11 of Acid Sp. Abs. (L/m/mg-C) Weak Hydrophobic Acids Fulvic Acid Fractions 1 Hydrophilic Acids 0.1 Same DOC 200 250 300 350 400 450 500 550 600 650 Wavelength (nm) 254 nm CEE697K Lecture #21
Formation Potentials of NOM Fractions 12 70 FP 60 High dose TTHMFP (µg/mg-C) 50 Forces 40 reaction to endpoint 30 20 10 0 Weak Acids Fulvic Acid Humic Acid Neutrals Neutrals Bases Bases Acids 12 CEE697K Lecture #21 Hydrophilic Hydrophobic
Aged leaves from 3 locations in Wachusett watershed Leaching Experiments 13 White White Red Oak Pine Maple CEE697K Lecture #21
14 Level 2 ecoregions CEE697K Lecture #21
Leaching of leaves 15 Dark 1.8 9 Maple UV Non-sterile 1.6 8 Oak UV conditions Pine UV 1.4 7 Maple SUVA UV 254 Absorbance (cm -1 ) Substantial slow Oak SUVA Pine SUVA 1.2 6 SUVA (L/mg-C/m) leaching of organics 1.0 5 0.8 4 0.6 3 0.4 2 0.2 1 0.0 0 0 2 4 6 8 UV Leaching Time (days) 254 x ≡ 100 SUVA CEE697K Lecture #21 DOC
Leaching: Sp-THAAFP 16 180 Filtered leachate Specific THAA Formation ( µ g/mg-TOC) 160 Chlorinated & 140 analyzed for 120 THAAs 100 Mostly 80 trichloroacetic acid 60 THAA yield 40 20 divided by DOC 0 Specific THAA Dark Maple #1 Dark Maple #2 Dark Oak #1 Dark Oak #2 Dark Pine #1 Dark Pine #2 Light Maple Light Oak Light Pine D.Biocide Maple D.Biocide Oak (precursors) Specific THAA Formation for Leaching Study CEE697K Lecture #21
COOH CHO COOH COOH Lignin Monomers OCH 3 CH 3 O OCH 3 17 OH OH OH OH 4-Hydroxy- Syringic acid Vanillic acid 4-Hydroxy- benzoic acid benzaldehyde CH 3 CH 3 Aromatic structures CHO CO CHO CO from CuO degradation CH 3 O OCH 3 OCH 3 OCH 3 Syringyl OH OH OH OH Vanillyl Vanillin 4-Hydroxy- Acetovanilione Syringaldehyde acetophenone Cinnamyl COOH COOH CH 3 CO CH 3 O OCH 3 OCH 3 OH OH OH CEE697K Lecture #21 4-Hydroxy- Acetosyringone Ferulic acid cinnamic acid
Lignin 18 From: Perdue & Ritchie, 2004 CEE697K Lecture #21
Other plant products 19 Steroids Nucleic Porphyrins Acids Water Soluble Acids Terpenoids Amino Acids Misc. N & S Mevalonic acid compounds Acetate Flavonoids Unsaponifiable Liquids Pyruvate Proteins Shikimic Acid Saponifiable Liquids Carbohydrates Nitrogenous Aromatic Compounds precursors CEE697K Lecture #21 From: Robinson, 1991 Activated non-N precursors
O COOH COOH Cl C OH 1, 2, or 3 chlorinations Cl initially Cl Cl Cl Cl And or chlorination of OH NH 2 NCl 2 NH 2 the amine NH 2 Aromatic Amines Cl Cl 20 COOH COOH Cl Cl Cl Cl Cl Cl - NCl 2 H OH O NH 2 Cl 2 Cl Cl OH O Proposed degradation OH OH OH pathway for 3-amino Cl OH Cl Cl COOH benzoic acid. Cl COOH Cl COOH O Cl Cl Cl Cl Cl Cl Cl Cl Cl O O O Cl Cl Cl O Cl OH COOH Cl OHl COOH COOH Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl HO HO O O O O OH Cl Cl Cl Cl Cl -CO 2 O COOH COOH Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl HOOC Cl HO O O HO O Cl Cl Cl Cl OH Cl Cl O Cl CEE697K Lecture #21 Initial decarboxylation that we would predict for the para substituted compound is less likly here because the intermediate is not resonance stabilized
THMs HAAs HANs TOX Unknown TOX Aromatic 0.08 0.7 6.0 7.7 7.8 Cl 2 Demand (M/ M) 0.07 0.6 0.06 Amines 0.5 0.05 M-Cl/M 0.4 M/M 0.04 21 0.3 0.03 0.2 0.02 0.1 0.01 0.00 0.0 Anthranilic acid 3 Aminobenzoic 4 Aminobenzoic acid acid Unknow n TOX Unknow n 16% THMs TOX 25% THMs 51% HANs 31% 1% THMs 38% Unknow n TOX 58% HAA6 HAA6 HAA6 45% 15% HANs 15% HANs 3% 2% CEE697K Lecture #21 4-Aminobenzoic Acid Anthranilic Acid 3-Aminobenzoic Acid
Compare with Model Compounds 22 10-90% ile range for NOM Aromatics Wide Nucleic Bases 1000 Simple Aliphatics Amino Acids range for Amino Sugars TriHAA Precursors ( µ g/mg-C) 100 models Narrow 10 range for NOM 1 0.1 0.01 0.01 0.1 1 10 100 1000 10000 THM Precursors ( µ g/mg-C) CEE697K Lecture #21
Elemental Ratios 23 Van Krevelen Plot From: Perdue & Ritchie, 2004 CEE697K Lecture #21
Size and Charge Relationships for NOM Fractions from: Bezbarua and Reckhow, 1995 -25 Hydrophilic Acids -20 Charge Density @ pH 7 (meq/g-C) -15 Humic Acid -10 Fulvic Acid -5 Weak Hydrophobic Acids Neutrals 0 Hydrophobic Bases Hydrophilic Bases 5 10 100 1000 10000 100000 Molecular Weight 24 CEE697K Lecture #21
25 Van Krevelen diagram for the Dismal Swamp DOM, compound classes are represented by the circles overlain on the plot. The distinctive lines in the plot denote the following chemical reactions: (A) methylation/demethylation, or alkyl chain elongation; (B) hydrogenation/dehydrogenation; (C) hydration/condensation; and (D) oxidation/reduction. CEE697K Lecture #21 Sleighter & Hatcher, 2007 [J. Mass Spec. 42:559]
Fate & Transport: 26 Watershed Water Treatment Plant “Full-scale monitoring Natural system Engineered System Physical processes Physical processes Chemical processes Chemical processes Biological processes “Lab-scale Biological processes simulation Fundamental Testing CEE697K Lecture #21
Biodegradation of leaf leachate 27 ~ 50% biodegradable Bacteria grow preferentially on 1.2 Phase 1 (C o =6.7 mg/L) NOM <3000 amu Phase 2 (C o =5.4 mg/L) 1.0 ) Phase 3 (C o =7.9 mg/L) o 0.8 0.6 0.4 0.2 DOC F 0.0 0 20 40 60 80 100 ti Time (Days) CEE697K Lecture #21 R
Leaching & Biodegradation 28 0.6 Maple 60 120 Surface Waters Groundwaters 0.5 Specific THM-SDS ( µ g/mg-C) 50 Specific THMFP ( µ g/mg-C) 100 Pre-exponential Term (a) Oak 0.4 Pine 40 80 0.3 30 60 0.2 20 40 0.1 10 20 0 0 0.0 0.0 0.2 0.4 0.6 0.8 1.0 CEE697K Lecture #21 Cumulative Frequency
Transport & Soil Properties 29 Case study: TOC & soil properties Parallel watersheds in Australia (Cotsaris et al., 1994) Clearwater Creek, high clay content: 2.5 mg/L TOC Redwater Creek, sandy soil: 31.7 mg/L TOC Presumed Attenuated of TOC by adsorption to clay soils Impacts on specific NOM components & precursors ?? CEE697K Lecture #21
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