Table 3.
Works on graphene-based catalysts used in photocatalytic ozonation.
| Photocatalysts | Target pollutants | Radiation Source and Reactor | Ozonation Conditions | Process Performance | Reference |
|---|---|---|---|---|---|
| SWNTs, MWCNTs, C60, g-C3N4, and rGO | Oxalic acid C0 = 10−3 M |
300 W Xe lamp with visible filter Semi-batch tank V = 300 mL |
CO3g = 50 mg L−1
Fg = 100 mL min−1 pH0 = Not provided Ccat = 0.1 g L−1 |
Oxalic acid removal Ozonation time = 30 min O3 alone: <5%; O3/rGO: ca. 90%; Rad/O3/rGO: ca. 95% |
[118] |
| g-C3N4-rGO (1–4% rGO) | Oxalic acid s C0 = 1.1 × 10−4 M |
500 W High Pressure Xe Lamp Semi-batch tubular reactor V = 1L |
mO3 = 75 mg h−1 Fg = 1 L min−1 pH0 = Not provided Ccat = 0.2 g L−1 |
Oxalic acid removal Ozonation time = 40 min O3 alone: 7.1%; Vis Rad/O3/g-C3N4-rGO: 70.6%; UV-Vis Rad/O3/g-C3N4-rGO: 93.2%; |
[51] |
| TiO2-rGO | Bisphenol A (BPA) C0 = 10 mgL−1 |
175 W HighPressure Hg lamp with quartz well (max. at 365 nm) Semi-batch tubular reactor V = 1 L |
CO3g = 80 mg L−1 Fg = 1 mL min−1 pH0 = Not provided Ccat = 0.5 g L−1 |
TOC removal Ozonation time = 45 min O3 alone: 18.7%; O3/TiO2-rGO:19.7%; Rad/O3/TiO2-rGO: 60.7% |
[52] |
| TiO2 (P25)-rGO(0.33% rGO) | Phenol (P), nitrophenol (NP) and chlorophenol (CP) C0 = 20 mgL−1
Hydrogen peroxide: 70 μL |
150W Xe Lamp with visible filter 12 mW cm−2 0.1 L tubular semi-batch reactor |
O3 from electrochemical generation. H2O2 was also used. CO3g = 4.1–7.6 g L−1 CH2O2 = 700 L·L−1 when applied Ccat = 1 g L−1 |
Compound removals Ozonation time: 30 min O3/TiO2-rGO: P: 58%; NP: 100%; CP: 90% Ozonation time: 20 min O3/H2O2/TiO2-rGO: P: 70%; NP: 100%; CP: 90% |
[119] |
| TiO2-N-rGO and TiO2-S-rGO (2–3% rGO) |
Diphenhydramine (DP) C0 = 100 mgL−1 |
Heraeus TQ 150 medium-pressure Hg vapour lamp, 350–700 nm (140 W m−2) Semi-batch tank reactor V = 7.5 mL |
CO3g = 50 mg L−1
Fg = 150 mL min−1 pH0 = Not provided Ccat = 1 g L−1 |
DP removal Ozonation time = 1 h O3 alone: <5%; Rad/O3/TiO2-N-rGO: ca. 60%; Rad/O3/TiO2-S-rGO: ca. 65% |
[49] |
| TiO2-N-GO/titan grid sheet | Cefixime, C0 = 5–20 mgL−1 |
432 visible LEDs (7.45 W m−2) Semi-batch tubular reactor V = 1 L |
CO3g = 24 mg L−1
Fg = 150 mL min−1 pH0 = 4–10 Ccat = 0.25 g L−1 |
Cefixime removal at pH = 10 Ozonation time = 2 h O3 alone: ca. 50%; O3/TiO2-N-GO: ca. 70%; Rad/O3/ TiO2-N-GO: ca. 80% |
[53] |
| ZnO-rGO | Perfluorocatanoic acid (PFOA) C0 = 10 mgL−1 |
254 nm low pressure Hg lamp in a quartz well Semi-batch tubular reactor V = Not provided |
Tª = 15–45 °C mO3g = 50 mgh−1 Fg = 150 mLmin−1 pH0 = Not provided mcat = 0.2 g CPersulfate = 100 mgL−1 |
PFOA removal Ozonation time = 4 h O3 alone: ca. 10%; Rad/O3/ZnO-rGO: ca. 85%; Rad/O3/ZnO-rGO/S2O82−: ca. 99% |
[50] |
| TiO2-GO (0.3–2% GO) |
Primidone (PRM) C0 = 20 mgL−1 |
44 visible LEDs (max. 425 nm) 25-455 Wm−2 Semi-batch tank V = 0.5 L |
CO3g = 10 mgL−1 Fg = 35 Lh−1 pH0 = Not provided Ccat = 0.125–0.5 gL−1 |
100% PRM removal Ozonation time: 10 min 70% TOC removal Ozonation time: 120 min Optimum GO %: 4 |
[54] |
Nomenclature: C0 = initial pollutant concentration; V = working volume; CO3: dissolved ozone concentration; CO3g: ozone gas concentration; mO3 = ozone mass flow rate; Fg: gas flow rate; Ccat: catalyst concentration; mCat = catalyst mass; pH0 = initial pH.