?? 4.1 ??? ???? ?? ???????? K? ?? ??? ??? 25 ??? ??? ? ???. - PowerPoint PPT Presentation

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?? 4.1 ??? ???? ?? ???????? K? ?? ??? ??? 25 ??? ??? ? ???.

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Title: ?? 4.1 ??? ???? ?? ???????? K? ?? ??? ??? 25 ??? ??? ? ???.


1
4? ?? ??
  • ?????
  • 20081425
  • ???

2
?? 4.1 ??? ???? ?? ???????? K? ?? ??? ??? 25 ???
??? ? ???.
  • ? ?? ?????, ??? ??? ???? ??
  • ???? ???? ??
  • ? ?? ?? ???? ??????? ???
  • ???.
  • ???, ??? ???? ?? ? ? ???? ?
    ?? ??? ????. 25??? ??.

3
??? ? 4.2?? ???? ? ??? ?? ??? ?? ????.
4
?? 4.2 ?? ????? K? ??
  • ?? 4.1??? ? ?? ?? ? ??? 25???? 10??? ????.
  • ? Stumm? Morgan14? ?? ???? ??? ??? ???? ???? ??
    ????? ???.

5
  • 10???? ??? ?? ??? ??? ??? ?(23)? ????.
  • ?? ????, ?? ??? 25???? ??? 0.85? ? ??. ??? ???
    ?????? ? ?? ??? ???? ?? ??? ? ?? ??(??)?
    ????, ??? ????? ??? ????.

6
  • ????? ?? ??? ??? ???? ??? 10-1000 atm?? ???? ??
    ??? ???? ???? ??? ??? ? ??. ??? ????, ???? ????
    ?? ? ??? ??? ???? ?(24)? ?? ??? ??? K? ???? ???
    ??? ? ??.
  •                 
          (24)
  • ???, ? ?????? ??? ?? ? ??( )? ????(P
    1 atm), K? ?????? P? ?????. ? ?? ? ??? ??
    ?????? ????, ? (24)? ??? ????.

7
  •                     (25)
  • ???, ? ??????? ??????, ? ??? ?? ????, ?
    ??? ????. ???, ? ??????( ).
  •    Stumm? Morgan14? ????? ???? ??? ?? ??? ?? ???
    ??? ????? ?, ?? ?? ????? ???? ??? ??? ????. 1000
    atm? ??(?? ?? 10,000m)?? ???? ???? ? ??
    ?????? 8.1? ??.

8
Example 4.3 Activity Corrections for the
Carbonate System
  • In exact calculations with the carbonate system
    in a groundwater ( ) we need
    activity corrections. pH is measured
    operationally with standard buffers, that is, as
    (infinite dilution). It is convenient to
    retain concentration units for the carbonate
    species (conservative quantities like total
    inorganic carbon or alkalinity have to be
    expressed as concentrations). Thus we apply our
    corrections to the equilibrium constants, K, and
    then make our calculations numerically or
    graphically as before.

9
  • Solution
  • Using the Guntelberg approximation equation (3),
    Table 4.3, we obtain

10
  • and for , the divalent carbonate ion has a
    valence Z 2
  • In this example, the corrections on p? values for
    activity coefficients are not very large. We did
    not use an activity correction for assuming
    that pH measurements correspond most closely to
    an activity measurement.

11
Example 4.4 Activity Coefficient of
Nonelectrolytes
  • Find the activity coefficient of dissolved oxygen
    , in seawater ( ).
  • Solution Morel and Herlng16 give the general
    empirical equation for neutral molecules
  • where f is the activity coefficient of the
    neutral molecule and I is the ionic strength, M.
    At ionic strengths less than 0.1 M, the activity
    correction is less than 2. In seawater it
    becomes significant. For molecular oxygen in
    seawater, the activity coefficient is
    according to the equation above.

12
  • Actual studies of dissolved oxygen in seawater in
    the laboratory have yielded the following (more
    accurate) equation fur the activity coefficient.
  • which yields an activity coefficient of
    . Neutral molecules have activity coefficients
    greater than 1.0 in electrolyte solutions and
    this is known as the "salting out" effect.

13
Example 4.5 Langmuir Adsorption Model
  • ??? ?? ????? ? 1??? ?? ??? 5.98??? ?? ?? ??????
    ?? ????(??Schecher and McAvoy22). ???? ???? ????
    ?? Langmuir ???? ?  ??? ? ??? ????

14
Dissolved Adsorbed
ConcentrationM ConcentrationM,ConcentrationS-M
mol L-1 mol L-1
4.57 10-7 5.43 10-7
6.28 10-5 4.34 10-5
0.000148 6.37 10-5
0.000244 7.24 10-5
0.000345 7.71 10-5
0.000450 7.69 10-5
0.000655 8.16 10-5
0.000759 8.35 10-5
15
  • ? ??? ??? ??? ???? ?(75)?
  • ??? ? ? ??.
  •    ??? ??? ?? ??/?? ???? ???
  • ???
  • ? ?? ? ?? ??? ????. ? ??.
    ?? ??? 10-3 M?? ??, ??? ??? ? ??? ?
    ??(??? ??? ?? 4.4? ????? ?? ??? ???? ???? ??). 

16
  • ?? 4.5? ??? ??? ??? ????. ??? 9 10-5 mol L-1?
    ?? ??? ??? ???? ???? ?? ????(?)? ????. ??? ????
    ???(??)? ?? Langmuir? ??? ????.
  • ???? ?? ??? ?? 4.6? ?????. ??? ?? ??
    ? ?? ? ?????. ???? ? ?? 1.1039 104 L/mol
    ??. ????, ??? ? ??? ??. ???
    ??? ????? . Q.E.D??.

17
?? 4.6 ?? ??? ?? ??? ??? ?? ?? ?? ??
  • ??? ?? ?? ??? ???, pH 7 ?  I 0.1 M?? ?? ?? ???
    ???.
  •                               
  • Dzombak and  Morel26? ??? ?? ??, ?? ?? ????? ??
    ?? ??? ????.
  • ? I 0.1 M, pH 7??? ?? ?? ?? ? ??? ?? ?? 4.9?
    ????.
  •                      

18
  • ? (89a)? ? ???? ?? ??(??) ? ??? ?? ???.
  •             
  •                                       
  • ? ?? P? ??? ??
  •     
  •                         
  •                           

19
  • ?? ?????,  pH 7 ? I 0.1 M?? HFO? ??? ???? H
    ??? ?? ?? ??? ?? 0.127? ??? ?? ?? ??? ?? ????. ??
    ??? HFO? I gt 0.01 M? ???? pH ?? 7?? ?? ?? ? 9??
    ? ??? ?? ????.

20
?? 4.7 ?-??, ???(???), ?? ???
  • ????? ???? ???? ? ???? ??? ? ??
    ???? ??? ???. ??????? ??, ????. log?? ? pH? ???
    ?????. pH ??? ?? ?? ? ???? ??? ??? ??? ????. ?
    ????, ????? ??? ? ??. ??? ??? ??????? ????? ????
    ? ??? ??? ??? ??? ???.

21
  • ?? ????? ? ? ? 4.2? ??? ?? ?? ?? ??? ????. ???
    ???? ??? ? ?? ????? ?? ????. ????? ??(?? ??)
    ????? ?? ??? ? ??. 
  • Species(???)
    (six species)
  • Components(????) (three
    components)

22
  • ? ????? Type I ????? ?? ?? ??? Type II ?????. ??
    ?????, ??? ???? ?? ?? ? ?? ????? ??? ? ? ??. ???
    ? ???? ??????? Na? ??? ? ??. ???? ??? ????
    ? ??? ????? Na ??? ??? ??? ?? ?? ????.
    ???? ???? ?? ????? ??? ??? ??? ? ??. ? ????? ????
    ????? ??. ??? ????? ???? ??(??? ??? ???). 

23
  • ??? ??? ?????? ????. ?? ???? ?? ?? ?? ??? ????(??
    ??). ??? ????? ??? ???? ??(?? ??).

24
  • ?? ? ??? ?(i)-(vi)? ??? ?? ??? ? ??. ??? ? ?? ??
    ??? ?? ? ????? ??? ????.

Components Components Components Components Components Components
Species
1 1 0 1 6.3
2 1 0 0 0
3 1 0 -1 -10.2
4 0 1 0 0
5 0 0 -1 -14
6 0 0 1 0

25
  • ? ?????? ???? ?? ???? ??.
  •      TOT Carbonate
  •     TOT Na
  •     TOT H
  • ???? ?? ????? ? ?? H??? ???? ?? ??? ??? ?? ??.
    H?? ??? ???? ?? ?? pH ????. ? ?????? ???? ???
    ????? ????(???) pH ?? ? ??? ???? pH ?? ???? ??? 
    ???. TOT H ?? ????? ??????. ??
    ??? ?? ?????? ????.

26
  • ?? ??, ? ??? ???? ??? pH?? ?? ??? ???. ??? ?????
    ???, ??? ??? ???? ?????? ??? ??? ?? 4.10? ??
    ????? ?? ?????.  M ???? ???? ?? ???
    pH 8.2?? ????.  ??? ????, ???? ??? 
    , pH 8.2?? ?????. ??? ??? ?? ?
    ??? ?? ???  , ,
    ,
  • pH 8.22??.

27
?? 4.8 f(pH)? ?? ???? ? ??? 
  • ? ????? ??? ??? ?? ???? ???? ?? ?????. ??? ?? ?
    ??? ???? ??. ??? ??? pH?? ? ????? ?????. ????
    ????? ???? ??(??)?? ? ???? ????. ?
    ????? ?? ? ?? ??? ????(??? ??? ?????
    Cüntelberg ?? ??? Davies ???? ???? ?? ??? ???
    ????? ?? ? ??).  

28
?? 4.10 ?? 4.7? ?? ??? Log C? pH? ??
29
  • ?? ??? ??? ???? ????? ????. ?? ????? ?? ?????
    ???? ? ? ????. ?? ??
    ???? ?? ??? ??? ????? ????.
  • ????? ??? ???? ???? ???? ?? ?????, ?,

30
  • ??? ?? OH-? ??(ova) ????? ???? ???, ??? ????
    (H)? ??? ??? ??? ? ?? ?,
  • ?? ? ?? ??? ?? ? ? ??.
  • Species
  •   Components

31
  • ????? ????, ??? ?? ?? ?? ???  Fe(III) ????
    ??? ? ??. ??? ? ??? ????? ?? ????? 
    ????? ?????. ?? ??? ?? ?? ???? ????? ???? ?????
    ?? ???? ????.
  • ????? ?? pH ??? ? ?????? ?? ????? ??. ??? ????
    ?????? pC ? pH? ??? ???? ???? ??(????, 0.2??? pH
    ??)??? ?? pH? ??? ???. (MacµQL??,17 ??? ? ??? ??
    ????? ???? ????.)

32
  • ? ?????(mass action expressions)? ??? ?? ???? ???
    ?? ????? ??? ?? ??????. ??? ? ?? ??
    ??? ??? ???. ???? ??? ???? ??? ? ???? ?? ????
    ??? ?? ???? ??? ???? Type III ?????. ??? ??
    ?????? ?????.

33
(No Transcript)
34
  • ? ??? ???? ????? ????? ??? ??? ??. ? ????? pH?
    ?? ?? ?? ?? ???.

Components Components Components Components Components
Species Species Species Species Species
1 1 3 3.3
2 1 2 0.5
3 1 1 -2.6
4 1 0 -9.8
5 1 -1 -18.5
6 0 -1 -14.0
7 0 1 0
??? ?? 4.11? ???? ??. ??? ?????? ???? ??.
35
?? 4.9  -FeOOH??  Pb(II)? ?? ???
  •   a-FeOOH(geothite)?? M Pb(II)? ??? ? pH?
    ???? ???? ?? ??? ????. ????? ??? ??? ??. ??? ?
    ???? ??? ??? Cd, Cu, Zn, Pb, Hg? ?? ??? ????
    ????? ?? ?? ???? ??? ??? ????.
  • ??????? ???? ?? log C ? pH? ??? ?????.  ??
    ????(capacitance) 2.9 ? ?? ??? ???? ???
    ????. ??? ?? ??? 14.7 ? ????. ?? ??? ?? SOH
    0.000135 , ????? ?? 0.1 , ????? 0.01
    ??.

36
?? 4.1 25 ?, ??(??)?? ? ???? ?? log C?
pH? ??(?? 4.8)
37
  • ?? ?????? ????
  • Species(???) 
  •         
  • ?? "gt"? ? ?? ???? ???. ? ??? ??( ?
    ????, ???)? ?? ?????. ? ??????? ?? ??? ??
    ??? ? ??. ??? ? ?? ?? ??(??) ?? ?
    ?????, ??-? ??? ??? ? ?? ?? ??(??) ?? ? ???
    ? ??. ??? ???? ?? ???? ??? ???? ??? ??? ? ??
    ? ??? ??? ???. 

38
  • ????? , , ? ??? ???? ????. ? ???,
    ??, ?? ??? ??? ???? ?? ?? ?? ??? ??? ?? ?????. ??
    7?? ???? ?? ??? ? ?? ????? ??? ??? ? ??. ???? ???
    ???? ??(capacitance model)? ??? pH? ?? ?? ????
    ???, ??????? ?? ??? ????? ??.
  •    Components(????) , surface
  • charge, ,
    '(four components)

39
  • ? ?????? ????? ??? FeOOH? ???? ????.
  • Surface charge
  • ????? ??? ?? ????.

40
  • ????? ?????, ??? ??? ????? ? ??? ??? ???? ?? ?? ?
    ? ??.
  • (i)                    
  • (ii)                    
  • (iii)                   
  • (iv)                    
  • (v)                    
  • (vi)                    
  • (vii)                   

41
A B C D E F
1 FeOOH surfCharge Pb2 H log K
2 adsorbent charge 1 total free
3 FeOOH 1 0 0 0 0
4 FeOO- 1 -1 0 -1 -9
5 1 1 0 1 6.7
6 FeOOPb 1 1 1 -1 -0.52
7 (FeOO)2Pb 2 0 1 -2 -6.72
8 Pb2 0 0 1 0 0
9 H 0 0 0 1 0
10 1.00 0.00 1.00E-0.6 1.00E-0.7
11 constantCap model "constantCap", "diffuseLayer" or "tripleLayer" model "constantCap", "diffuseLayer" or "tripleLayer" model "constantCap", "diffuseLayer" or "tripleLayer" model "constantCap", "diffuseLayer" or "tripleLayer" model "constantCap", "diffuseLayer" or "tripleLayer"
12 14.7 specific surface area in m2 specific surface area in m2 specific surface area in m2 specific surface area in m2 specific surface area in m2
13 1.35E-0.4 no. of active surface sites in mol/g no. of active surface sites in mol/g no. of active surface sites in mol/g no. of active surface sites in mol/g no. of active surface sites in mol/g
14 0.1 conc. of adsorbent in g/l) conc. of adsorbent in g/l) conc. of adsorbent in g/l) conc. of adsorbent in g/l) conc. of adsorbent in g/l)
15 0.01 ionic strength in mol/l ionic strength in mol/l ionic strength in mol/l ionic strength in mol/l ionic strength in mol/l
16 2.9 capacitance of inner layer in F m-2 capacitance of inner layer in F m-2 capacitance of inner layer in F m-2 capacitance of inner layer in F m-2 capacitance of inner layer in F m-2
  • ? ?? ??? ?? Westall? ??? MICROQL.? Beat Müller?
    ???? ????? MacµQL? ???? ??????? ??? ??? ?? ????.

42
  • FeOOH? ????? 10?, 2?? 1.0? ???? ??? ?????. ?
    ??(??)? ??? 0.10.000135 mol/L??.
  •  
  • 7?? ??? ??? ?? 3??? ??? ??? ?? 4.1? ? ??? ?????.
    pH 6.3????, ?? ???? ???? ????. ??? ???? pH
    6.?? ??? ?? ?? ??. pH? 7?? ? ?, ??? ?? ?? ????
    ??????(????? ?? ). ? ???? ?? ????
    ??(mol/L)? ???? ??? ?? ?? ??? ????.

43
pH
4 6.47 10-6 3.00 10-8 7.00 10-6 4.22 10-11 2.25 10-15
5 8.35 10-6 6.89 10-8 5.07 10-6 3.05 10-9 3.73 10-13
6 1.00 10-5 1.60 10-7 3.15 10-6 1.59 10-7 4.54 10-11
7 1.09 10-5 4.72 10-7 1.26 10-6 8.83 10-7 7.42 10-10
8 1.08 10-5 1.27 10-6 4.59 10-7 9.94 10-7 2.24 10-9
9 9.67 10-6 2.74 10-6 1.77 10-7 9.95 10-7 4.68 10-9
10 8.04 10-6 4.37 10-6 7.42 10-8 9.92 10-7 7.72 10-9
44
?? 4.12 ?? 4.9??? geothite( FeOOH)? ?? ???? ?? 
M ? log C? pH? ??
45
  • 2? ?? ??? ? ??? ?? ???? ??, ??
    pH??? ? ????, ?? pH???
  • ??, , ? ????.

46
?? 4.10 ???  ? ? ???? ??
  • ???? ??? ???, ????? nitrate? ??? ???. ????(??)
    ???? ??? ??, ??? ? ??? ?????(??????) ?? ? ????. ?
    ??? 5104 mol/L? ????. pH? ??? ?? ????, ????,
    nitrate? ??? ???. ?? ???? ????? ????. 5.52.
    ? ?? Müller.17? ????.

47
  • ?? ? ?? ???? ????. ??? ???? ?? ??? ??? H2? O2?
    ??? ??? H2O ? ??????? ??? ? ??. ??? ??? ?????
    H2(g)? O2(g)? ???? ?? ??? ???? ?? ??.
  •   
  •    Species
  • (Seven Species)
  •    Components (three components)

48
  • ???? ????, ??????? ? ???? ?? ?? ??. ?? pH
    ????, ??? ?????? ? ????? ??. ????? ??? ???? ????
    ???, ?? ??, nitrate ??? ??????. ???? nitrate?
    ???? ?? ????, ?? ?????
  • ? ?? ????? ? ??? ??????? ? ??????? ???? ?
    ?? ????. ??? ??? ??? ?? ?, ? ????? ??? ?????
    ????? ????. ?(half) ??? MINTEQ? MINEQL.21.22?
    ????  ??? ??? ??.

49
  • (?? ? ?????? ???? ????? ???? . ??? ? ????  ?????
    ???? ?? ?? ??? ??? ?? ??.)

50
  • ???? ?? 7?? ????
  • (i)                         
  • (ii)                 
  • (iii)                
  • (iv)                   
  • (v)                     
  • (vi)                         
  • (vii)                        

51
  • ?????? ??? ??? ? ?? ?? ??? ??? ??.
  •  
  • (initial value)

52
A B C D E
1 log K
2 TOTAL FREE FREE
3 1 0 0 0
4 1 8 9 109.9
5 1 8 10 119.2
6 0 -4 -4 -83
7 0 2 2 0
8 0 1 0 0
9 0 0 1 0
10 5.00E-04 3.00E-06 3.00E-08 (concentration )
53
  • ?? ???? ?? 4.13? ??????. ?? pH ???? ? ????,
    ?? ????? ????? ? nitrate? ??? ???. pH 5?? pH?
    ????, ? ?????? ?? ?? ??? ????. ??? ??? pH?
    ???? ?? nitrate???? ????. ?
  • 5.52? ? ? ????,  ?????? ? ? ??
    ?? ??(??? ??? pH 4?? M, pH 10?? ?? ?? M
    ????? ??? pH 4? ? ? , pH10?? ? ? M).
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