Reduction of Contaminants in Soil and Water By Direct Electric Current - Electrokinetics for Petroleum and Environmental Engineers - page 42

200

KS (I)
KS (h)
KG (h)
KH (h)
SS (h)
MS (I)
MS (h)
SSRM

Cd +2

K ef = 0.12
[Cd +2 ] ~ 0.0002 M

K ef = 0.05
[Cd +2 ] ~ 0.006 M

160

K ef = 0.05
[Cd +2 ] ~ 0.008 M

120

80

K ef = 0.015
[Cd +2 ] ~ 0.04 M

40

K ef = 0.008; Synthetic Soil
Reference Matrix (SSRM)

0

0 2000 4000

Cumulative Electrical Charge, C

6000 8000

Figure 2.2 Variation of Cumulative Flow with Electric Charge (Pamukcu and Wittle,
1992; Pamukcu, 2009)

0.5

0.15

Average values

K ef-blank KS = 0.14
K ef-blank MS = 0.04

0.425

0.4

0.359 0.364

0.12

0.3

0.09

0.2 0.06

0.03

0.1

0 0

Cs+ Cs+2

Major contributing ion in clay

Cs+ Cr+3 Pb+2 Zn+2

KS MS KG KH SS Molar Concentration

Figure 2.3 Variation of measured K ef factors with ion and soil type at same concentration
(Pamukcu and Wittle, 1992; Pamukcu, 2009)

treatise further strengthens the validity of these assumptions. Figure 2.3
presents the variation of the measured K ef for all soils and six selected major
contributing ions (Cd, Cs, Cr, Pb, Sr and Zn) in the bulk fluid, all applied
separately. There is a clear trend of decreasing K ef factor with increasing
ion concentration, where the normalized K ef of different soil types with
similar molar concentration cohort of different ions are shown. The values
are normalized by the measured K ef values of the respective “blank” clays,
those that were mixed and consolidated only with distilled water. At low