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TRANSCRIPT
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Assessment of bimetallic and trimetallic iron-based system for
persulfate activation: application to sulfamethoxazole degradation
Ghada Ayoub, Antoine Ghauch1
American University of Beirut, Faculty of Arts and Sciences, Department of ChemistryP.O. Box 11-0236 Riad El Solh – 1107-2020 Beirut – Lebanon
Prepared for Chemical Engineering Journal
April 7, 2014
Supplementary Material
6 Pages, 7 Figures
1 Corresponding author. Tel.: +961 1 350 000; fax: +961 1 365 217. E-mail address: [email protected]
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Fig. 1S. SEM images of CoFe (a) and AgFe (d) bimetallic systems as presented in Fig. 1. The corresponding X-ray maps of (b) Co (K1), (c) Fe (K1) and (e) Ag (K1) obtained from the two bimetallic systems CoFe and AgFe over the entire shown surface area (a, d). Areas of relatively high Fe concentrations are shown as bright regions in (c) and (f). In (b) less bright spots indicate areas of Co deposition whereas in (e) brighter spots indicate deposition of Ag at the surface of iron particles.
CoKa1 FeKa1
AgKa1 FeKa1Electron image
(b)(a) (c)
(d)
(b) (c)
Electron image
(e) (f)
(a)
29/01/2014 16:34:19
CoKa1
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Fig. 2S. SEM images of AgCoFe (a) and CoAgFe (d) trimetallic systems as presented in Fig. 2. The corresponding X-ray maps of (b) Ag (K1), (c) Co (K1) and (d) Fe (K1) obtained from the two trimetallic systems AgCoFe and CoAgFe over the entire shown surface area (a, e). Areas of relatively high Fe concentrations are shown as bright regions in (d) and (h). In (c), (f) and (g) less bright spots indicate areas of Co and primary Ag deposition whereas in (b) brighter spots indicate deposition of Ag at the surface of iron particles as second deposited metal after Co.
(a) (b) (c) (d)
(e) (f) (g) (h)
Electron image
Electron image
FeKa1
FeKa1
AgKa1
AgKa1
CoKa1
CoKa1
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Fe0/SMX/PS Fe0 Feeding
Fe2+/SMX/PS Direct Spiking
Fe2+/SMX/PS Sequential spiking
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
Ave
rage
% R
SE
Fig. 3S. Effect of direct vs sequential addition of Fe2+ compared to Fe0 in PS/SMX
solution on average % RSE over 30 min of reaction. Experimental conditions: [SMX]0 =
39.5 M, [Fe2+] = [Fe0] = 2.23 mM, m (Fe0) = 2.5 mg, pHi = 5.63.
Fig. 4S. Effect of bimetallic systems (CoFe and AgFe) and Fe0 on SMX degradation in
PS-free solutions. Experimental conditions: [SMX]0 = 39.5 M, m (Fe0) = m (AgFe) = m
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(CoFe) = 2.5 mg (2.23 mM), pHi = 5.63. Error bars represent uncertainty at 95%
confidence level.
0 10 20 30 40 50 600
0.2
0.4
0.6
0.8
1
1.2
Co2+/SMXAg+/SMXFe2+/SMX
Elapsed Time / [min]
[SM
X] /
[SM
X]0
Fig. 5S. Effect of transition metal ions Co2+, Fe2+, and Ag+ on SMX degradation in PS /
H2O free systems. Experimental conditions: [SMX]0 = 39.5 M, [Fe2+], [Co2+ ] = [Ag+ ] =
2.23 mM, pHi = 5.63. Error bars represent uncertainty at 95% confidence level.
Fe
100
CoFe 5:100
AgFe 5:100
AgCoFe 5:5:100
CoAgFe 5:5:100
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1Non-DisturbedDisturbed
Iron Based Systems
kobs
/ ko
bs (F
e)
Fig. 6S. Reactivity of plated and non-plated iron-based systems: vertical bars display the
ratio of k obs measured for each of the amended Fe0 systems to the k obs values measured for
the standalone Fe0 system (Kobs(amended Fe)
K obs (Fe) ).
Traces of non identified
by-products
SMX-Derivative
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Fig. 7S. Trace chromatograms of SMX treated in different metallic systems (Fe0, AgFe, and CoAgFe). Chromatograms with CoFe and
AgCoFe and similar to those presented; however, they are not shown for clarity. Experimental conditions: [SMX]0 = 39.5 M, [PS]0 = 1.0
mM, m (Fe0/ AgFe / CoAgFe) = 2.5 mg and m (Fe0) = 100 mg.
SMX
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