Supporting Information for

Transcription

1 Supporting Information for Activation of Persulfates by Graphitized Nanodiamonds for Removal of Organic Compounds Hongshin Lee a, Hyoung-il Kim a, Seunghyun Weon b, Wonyong Choi b, Yu Sik Hwang c, Jiwon Seo d, Changha Lee d, *, Jae-Hong Kim a, * a Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States b School of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Pohang , Republic of Korea c Future Environmental Research Center, Korea Institute of Toxicology (KIT), Jinju, , Republic of Korea; Human and Environmental Toxicology Program, University of Science and Technology (UST), Daejeon, , Republic of Korea d School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulju-gun, Ulsan , Republic of Korea *Corresponding author. J.-H.K.: jaehong.kim@yale.edu; phone: ; fax: C.L: clee@unist.ac.kr; phone: ; fax:

2 Text S1. Detailed experimental setup and procedure information of GC/MS system for phenol oxidation products analysis: Analysis for phenol oxidation products was performed on GC/MS system (HP6890/MSD5972A). The analytical chromatographic column was a Rxi -lms (60 m 0.32 mm, 1.0 μm). The GC oven column temperature program was 5 C/min rate 40 C to 90 C holding for 36.5 min, 15 C/min rate to the final temperature of 300 C holding for 2 min (total analysis time 62.5 min) as helium carrier gas (1.2 ml/min). Helium was employed as a carrier gas (1.2 ml/min). Injector was operated at 260 C in the splitless mode (1 min). MS monitoring conditions were set as follows: transfer line temperature (250 C); Ionization energy (70 ev); ion source temperature (280 C); Electron impact ionization in the positive mode and SIM (Selected Ion Monitoring) acquisition mode were used. Samples were extracted three times with n-hexane. 2

3 Table S1. Water quality parameters of field water samples DOC (mg C/L) DTN (mg N/L) Alkalinity (mg/l as CaCO 3 ) ph Ca 2+ (mg/l) Mg 2+ (mg/l) Conductivity (µs/cm) Turbidity (NTU) A 254 (cm -1 ) Surface water Ground water Sea water

4 1.0 with PBS buffer wihout PBS buffer 0.8 [Phenol]/[Phenoll] Figure S1. Phenol removal by G-NDs/PDS system with and without phosphate buffer solution: [Phenol] 0 = 1 mm; [G-ND] 0 = 0.1 g L -1 ; [PDS] 0 = 1 mm; 1 mm phosphate buffer at ph 0 = 7; Reaction time = 60 min. 4

5 1.0 with dissolved oxygen wihout dissolved oxygen 0.8 [Phenol]/[Phenoll] Figure S2. Phenol removal by G-NDs/PDS system with and without dissolved oxygen (by purging the solution with N 2 ): [Phenol] 0 = 1 mm; [G-ND] 0 = 0.1 g L -1 ; [PDS] 0 = 1 mm; 1 mm phosphate buffer at ph 0 = 7; Reaction time = 60 min. 5

6 Figure S3. (a) Photographs and (b) XPS spectra of G-NDs prepared at different annealing temperatures. 6

7 Figure S4. HR-TEM images of G-ND. 7

8 10 Intensity (%) Average particle size (nm) Particle size (nm) Figure S5. Particles size distribution and average particles size for suspension of G-ND in DI water measured by dynamic light scattering. 8

9 [Phenol]/[Phenol] Bare-NDs O-NDs G-NDs Figure S6. Phenol removal by surface modification nanodiamonds without persulfate systems: [Phenol] 0 = 1 mm; [ND] 0 = [O-ND] 0 = [G-ND] 0 = 0.1 g L -1 ; 1 mm phosphate buffer at ph 0 = 7 9

10 1.0 (a) 1.0 (b) [Phenol]/[Phenoll] g/l G-NDs 2 g/l G-NDs 5 g/l G-NDs 0.1 g/l G-NDs [Phenol]/[Phenoll] mm Phenol 5 mm Phenol 0.1 mm Phenol 0.2 mm Phenol Pseudo first order rate constant, k (min -1 ) (c) Pseudo first order rate constant, k (min -1 ) (d) G-NDs loading (mg/l) Phenol conc. (mm) Figure S7. (a, b) Phenol removal and (c, d) pseudo first order rate constant for the removal of phenol by G-NDs/PDS system as a function of G-NDs loading and phenol concentrations: [Phenol] 0 = 1, 5, 0.1, 0.2 mm; [G-ND] 0 = 1, 2, 5, 0.1 g L -1 ; 1 mm phosphate buffer at ph 0 = 7; Reaction time = 60 min. 10

11 [Phenol]/[Phenol] (a) Only G-NDs with Hydrogen Peroxide with Periodate with Peroxymonosulfate with Peroxydisulfate [Oxyanions]/[Oxyanions] (b) with Hydrogen Peroxide with Periodate with Peroxymonosulfate with Peroxydisulfate Figure S8. Decomposition of (a) phenol and (b) oxyanions by G-NDs in the presence of oxyanions: [Phenol] 0 = 1 mm; [G-ND] 0 = 0.1 g L -1 ; [PDS] 0 = [PMS] 0 = [Periodate] 0 = [Hydrogen peroxide] 0 = 1 mm; 1 mm phosphate buffer at ph 0 = 7; Reaction time = 60 min. 11

12 800 BET specific surface area (m 2 /g) Graphite Bare-NDs O-NDs G-NDs MWCNT SWCNT 0 Figure S9. BET specific surface area of carbon-materials. 12

13 After UV treatment Asym. str. S=O=S Symm. str. S=O=S Before UV treatment Intensity (a. u.) Quinoid ring Benzenoid ring Aromatic C-H out of plane bends Wavenumber (cm -1 ) Figure S10. FT-IR spectrum of G-NDs/PDS system with and without UV treatment: [Phenol] 0 = 0.1 mm; [G-ND] 0 = 0.1 g L -1 ; [PDS] 0 =1 mm; 1 mm phosphate buffer at ph 0 = 7; Reaction time = 60 min; UV light treatment (4 W germicidal Lamp, Philips Co) = 180 min. 13

14 (a) (b) y: Hydroxyl radical G-NDs/PDS Intensity (a. u.) y y y y Intensity (a. u.) Fe(II)/H 2 O 2 Only PDS Magnetic Field (G) Magnetic Field (G) Figure S11. EPR spectra obtained by spin trapping with DMPO in the (a) Fe(II)/H 2 O 2 and (b) G- NDs/PDS system at (a) acidic ph and (b) neutral ph: ((a): [DMPO] 0 = 10 mm; [G-ND] 0 = 0.1 g L -1 ; [PDS] 0 = 1 mm; 1 mm phosphate buffer at ph 0 = 7; Reaction time = ~10 min, (b): [DMPO] 0 = 10 mm; [Fe(II)] 0 = 0.1 mm; [H 2 O 2 ] 0 = 10 mm; ph 0 = 3; Reaction time = ~10 min). 14

15 Removal Recovery 0.10 after filtering and washing 8 G-NDs G-NDs/PDS Phenol conc. (mm) Figure S12. Removal and recovery of phenol by G-NDs with and without persulfate systems: [Phenol] 0 = 0.1 mm; [G-ND] 0 = 0.1 g L -1 ; [PDS] 0 = 1 mm; 1 mm phosphate buffer at ph 0 = 7; Reaction time = 120 min, Recovery: ph = 12 (NaOH), 90 C. 15

16 Figure S13. GC/MS spectra of products from phenol degradation by G-NDs/PDS system: [Phenol] 0 = 0.2 mm; [G-ND] 0 = 0.1 g L -1 ; [PDS] 0 = 1 mm; 1 mm phosphate buffer at ph 0 = 7; Reaction time = 90 min. 16

17 DI water Surface water Ground water Seawater [Phenol]/[Phenoll] Figure S14. Phenol removal by G-NDs/PDS system with different type of tap water: [Phenol] 0 = 1 mm; [G-ND] 0 = 0.1 g L -1 ; [PDS] 0 = 1 mm; Reaction time = 60 min. 17