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CEE 697K ENVIRONMENTAL REACTION KINETICS Lecture #10 Special - PDF document

10/17/2013 Updated: 17 October 2013 CEE697K Lecture #10 1 Print version CEE 697K ENVIRONMENTAL REACTION KINETICS Lecture #10 Special Topics: DCP in Water Primary Literature (e.g., Guthrie & Cossar, 1986) Introduction David A. Reckhow


  1. 10/17/2013 Updated: 17 October 2013 CEE697K Lecture #10 1 Print version CEE 697K ENVIRONMENTAL REACTION KINETICS Lecture #10 Special Topics: DCP in Water Primary Literature (e.g., Guthrie & Cossar, 1986) Introduction David A. Reckhow Guthrie 2  J. Peter Guthrie  B.Sc.  Department of Chemistry  Univ. Western Ontario Western University, London, Ontario, Canada, N6A 5B7  PhD Chemistry, 1968  Harvard University  DECARBOXYLATION AND ENAMINE FORMATION: MODEL SYSTEMS FOR ACETOACETATE DECARBOXYLASE  By James Peter Guthrie  Princeton Univ.  1970, Faculty, Western Guthrie, J. P. and J. Cossar (1986). "The University Chlorination of Acetone - A Complete Kinetic Analysis." Canadian Journal of Chemistry-Revue Canadienne De Chimie 64(6): 1250-1266. CEE697K Lecture #10 David A. Reckhow 1

  2. 10/17/2013 Mechanisms: Haloform Reaction 3  Chlorine + acetone  Morris & Baum, 1978  Brezonik, 1994 Pg 240-241 CEE690K Lecture #09 David A. Reckhow Haloform reaction: initial step 4  Three potential pathways to enolate  Reaction with water (K O ), hydroxide (K OH ), and proton (K H )  k f =K O +K OH [OH - ]+K H [H + ]  For acetone, the OH pathway dominates above pH 5.5   k [ H ][ A ]   f What is k r ? K a k [ HA ] r David A. Reckhow CEE690K Lecture #09 2

  3. 10/17/2013 Guthrie & Cossar Pathway 5  Scheme 1 CEE697K Lecture #10 David A. Reckhow Hydrolysis of 1,1-DCP 6  a The many forms of 1,1-DCP The product CEE697K Lecture #10 David A. Reckhow 3

  4. 10/17/2013 DCP equilibria I 7  Bell K’s 1.2 H+ alpha E 1.0 alpha Q alpha L alpha 5 0.8 Alpha 0.6 0.4 0.2 0.0 0 2 4 6 8 10 12 14 CEE697K Lecture #10 David A. Reckhow pH DCP equilibria II 8  Bell K’s 1e+1 1e+0 1e-1 1e-2 1e-3 Alpha 1e-4 1e-5 H+ alpha E 1e-6 alpha Q alpha L 1e-7 alpha 5 1e-8 0 2 4 6 8 10 12 14 CEE697K Lecture #10 David A. Reckhow pH 4

  5. 10/17/2013 DCP equilibria III 9  Guthrie K’s 1.2 1.0 0.8 H+ alpha E Alpha alpha Q 0.6 alpha L alpha 5 0.4 0.2 0.0 0 2 4 6 8 10 12 14 CEE697K Lecture #10 David A. Reckhow pH DCP equilibria IV 10  Guthrie K’s 1e+1 1e+0 1e-1 1e-2 1e-3 Alpha 1e-4 1e-5 H+ alpha E 1e-6 alpha Q alpha L 1e-7 alpha 5 1e-8 0 2 4 6 8 10 12 14 CEE697K Lecture #10 David A. Reckhow pH 5

  6. 10/17/2013 Loss of intermediates in lab water 11  21C, ultrapure water  (Nikolaou et al., 2001) CEE690K Lecture #09 David A. Reckhow 12  chlorine CEE697K Lecture #10 David A. Reckhow 6

  7. 10/17/2013 13  a CEE697K Lecture #10 David A. Reckhow Model 14  Guthrie model for 1,1-DCP degradation 1000 Chlorine Hydrolysis 100 10 Half-Life (hrs) 1 0.1 0.01 0.001 0.0001 4 5 6 7 8 9 10 11 12 13 14 CEE697K Lecture #10 David A. Reckhow pH 7

  8. 10/17/2013 LFER Analysis 15  Baiyang Chen analysis  pH 7-7.5  20-25C  Predicted hydrolysis rate constant for 1,1- DCP is 10 -1.66 hr -1  Half-life of 31.7 hr  6.1 x 10 -6 sec -1  (Chen, 2011).  Data point estimated from Nikolaou et al., 2001 Chen, B. Y. "Hydrolytic Stabilities of Halogenated Disinfection Byproducts: Review and Rate Constant Quantitative Structure- Property Relationship Analysis." Environmental Engineering Science 28(6): 385-394. CEE697K Lecture #10 David A. Reckhow Comparison with Chen 2001 16  Guthrie model for 1,1-DCP degradation 1000 Chen, 2011 Chlorine Hydrolysis 100 10 Half-Life (hrs) 1 0.1 0.01 0.001 0.0001 4 5 6 7 8 9 10 11 12 13 14 CEE697K Lecture #10 David A. Reckhow pH 8

  9. 10/17/2013 Loss in water heaters 17  Liu et al., 3.0 0.6 a No heating b 6 hrs incubation+heating 2.5 0.5 24 hrs incubation+heating 2013 48 hrs incubation+heating 72 hrs incubation+heating 0.4 2.0 1,1-DCP (  g/L) 96 hrs incubation+heating CP (  g/L)  In review 0.3 1.5 No heating 0.2 1.0 6 hrs incubation+heating 24 hrs incubation+heating 48 hrs incubation+heating 0.5 0.1 72 hrs incubation+heating 96 hrs incubation+heating 0.0 0.0 0 20 40 60 80 100 120 0 20 40 60 80 100 120 Reaction Time (hr) Reaction Time (hr) 8.0 2.5 c d No heating No heating 6 hrs incubation+heating 6 hrs incubation+heating 24 hrs incubation+heating 2.0 24 hrs incubation+heating 6.0 48 hrs incubation+heating 48 hrs incubation+heating 72 hrs incubation+heating 72 hrs incubation+heating 96 hrs incubation+heating DCAN (  g/L) 1.5 96 hrs incubation+heating TCP (  g/L) 4.0 1.0 2.0 0.5 0.0 0.0 CEE690K Lecture #09 David A. Reckhow 0 20 40 60 80 100 120 0 20 40 60 80 100 120 Reaction Time (hr) Reaction Time (hr) Profile of 1,1-DCP in Water Systems 18  1,1-Dichloropropanone concentrations compared to the corresponding TTHM concentration for all samples 8.0 6.0 San Francisco Jan(Cl 2 /NH 4 Cl) Charleston(ClO 2 / NH 4 Cl) San Francisco Apr (Cl 2 /NH 4 Cl) 4.0 1,1-dichloropropanone (  g/L) Ann Arbor(O 3 /NH 4 Cl) East Bay( Cl 2 /NH 4 Cl) 3.5 Cincinnati(Cl 2 ) 3.0 Minneapolis (NH 4 Cl/NH 4 Cl) Monroe(O 3 /Cl 2 ) 2.5 Wyoming( Cl 2 /Cl 2 ) 2.0 Pinellas County(Cl 2 /Cl 2 ) Pinellas County(Cl 2 /NH 4 Cl) 1.5 Knoxville(ClO 2 /Cl 2 ) 1.0 0.5 0.0 0 20 40 60 80 100 120 140 CEE697K Lecture #10 David A. Reckhow Chloroform (  g/L) 9

  10. 10/17/2013 19  1,1-Dichloropropanone concentrations compared to the corresponding TTHM concentration for all samples: focus on free chlorine plants 1.0 San Francisco Jan(Cl 2 /NH 4 Cl) Charleston(ClO 2 / NH 4 Cl) San Francisco Apr (Cl 2 /NH 4 Cl) 0.8 1,1-dichloropropanone (  g/L) Ann Arbor(O 3 /NH 4 Cl) East Bay( Cl 2 /NH 4 Cl) Cincinnati(Cl 2 ) 0.6 Pinellas County Minneapolis (NH 4 Cl/NH 4 Cl) Monroe Monroe(O 3 /Cl 2 ) Wyoming( Cl 2 /Cl 2 ) Cincinnati 0.4 Pinellas County(Cl 2 /Cl 2 ) Pinellas County(Cl 2 /NH 4 Cl) Knoxville(ClO 2 /Cl 2 ) 0.2 Wyoming 0.0 0 20 40 60 80 100 120 CEE697K Lecture #10 David A. Reckhow Chloroform (  g/L) Profile of TCP in water systems 20  1,1,1-Trichloropropanone concentrations compared to the corresponding TTHM concentration for all samples 5 San Francisco Jan(Cl 2 /NH 4 Cl) Charleston(ClO 2 / NH 4 Cl) San Francisco Apr (Cl 2 /NH 4 Cl) 1,1,1- trichloropropanone (  g/L) 4 Monroe Ann Arbor(O 3 /NH 4 Cl) East Bay( Cl 2 /NH 4 Cl) Cincinnati(Cl 2 ) 3 Minneapolis (NH 4 Cl/NH 4 Cl) Monroe(O 3 /Cl 2 ) Wyoming( Cl 2 /Cl 2 ) Pinellas County(Cl 2 /Cl 2 ) 2 Pinellas Co. Pinellas County(Cl 2 /NH 4 Cl) Knoxville Knoxville(ClO 2 /Cl 2 ) 1 0 0 20 40 60 80 100 120 140 CEE690K Lecture #09 Chloroform (  g/L) David A. Reckhow 10

  11. 10/17/2013 Lab 2 21  15 Oct 2013 experiment 0.3 Absorbance at 292 nm absinf = 0.012 0.2 0.1 0.0 0 100 200 300 Reaction Time (sec) CEE697K Lecture #10 Time (s) vs Abs David A. Reckhow Lab 2 22  1 st order plot -1 absinf = 0.012 b[1] -0.0128851211 -2 K = 46 hr -1 Ln (Abs-Abs   -3 -4 -5 -6 0 100 200 300 Reaction Time (sec) Time (s) vs ln abs-absinf CEE697K Lecture #10 David A. Reckhow Plot 1 Regr 11

  12. 10/17/2013 Lab 2 23  2 nd order plot 300 250 200 1/(Abs-Abs   150 100 50 0 0 100 200 300 Reaction Time (sec) CEE697K Lecture #10 Time (s) vs 1/(abs-absinf) David A. Reckhow Plot 1 Regr 24  Guthrie model 1000 Chlorine Hydrolysis 100 10 Half-Life (hrs) 1 0.1 0.01 0.001 0.0001 4 5 6 7 8 9 10 11 12 13 14 CEE697K Lecture #10 David A. Reckhow pH 12

  13. 10/17/2013 25  To next lecture CEE697K Lecture #10 David A. Reckhow 13

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