Table 3.

Brief summary of dye removal using selected advanced oxidation processes (last three years).

Object	Catalyst	Conditions	Effectiveness	Reference
Ozonation
Reactive Orange 16, Reactive Red 120, Direct Red 80	none	Found as optimal: pH 11, time 10 min, initial dye concentration 2000 mg L−1	52–64% dye removal	[74]
Direct Red 81	none	Found as optimal: pH 11, time 27 min, initial dye concentration 2000 mg L−1	61% dye removal	[193]
Acid Black 1	none	Found as optimal: ozone concentration 70 mg L−1, pH 6, time 20 min, initial dye concentration 200 mg L−1	95.5% decolorization	[167]
Direct Red 80	none	Ozone dosage 1.25 g L−1 min−1, pH 2–13.5 (optimal 12), initial dye concentration 100 mg L−1	99% decolorization, 27.4% COD removal	[77]
Reactive Red 239	none	Ozone concentration 20 mg L−1, pH 7, time 20 min, ozone consumption 106.9 mgO3 L−1, initial dye concentration 50 mg L−1	100% decolorization, 62% COD and 35% DOC removals	[35]
Acid Red 14	none	pH 10.7 (tested also 6.65), time 25 min, initial dye concentration 1500 mg L−1	93% decolorization	[194]
Crystal Violet	none	Ozone dose 2 mg L−1 min−1, pH 6.8, time 60 min, initial dye concentration 50 mg L−1	78% decolorization	[79]
Direct Black 22	none	Ozone dose 5 g h−1, pH 3–11 (optimal 11), time 30 min	55% COD removal	[195]
Rinsing effluents containing Reactive Blue 19, Reactive Red 239, Reactive Yellow 176	none	Ozone concentration 20 mg L−1, gas flow rate 0.5 L min−1, pH 7	60% COD removal after 60 min	[196]
Effluents after electrocoagulation containing mainly Reactive Black 5	none	Transferred ozone dose 600 mgO3 L−1, pH 11, time 30 min,	Above 90% decolorization	[75]
Catalytic Ozonation
Methyl Orange	Ni-based layered double hydroxides (Ni-LDHs) nanomaterials 1–3 g L−1	Ozone flow rate 109 mg h−1, pH 9, initial dye concentration 100–500 mg L−1	96% decolorization, 72% COD removal	[197]
Direct Black 22	Zinc slag 0.125–1 g L−1	Ozone dose 5 g h−1, pH 3–11 (optimal 11), time 30 min, 100 mg L−1 H2O2 addition	69% COD removal, 76% COD removal with H2O2	[195]
Reactive Blue 194	Activated carbon	Ozone concentration 178.8 mg L−1, time 40 min, pH 5–12, 25–50 °C, NaCl addition 5–50 g L−1	100% decolorization, up to 90% COD removal	[198]
Reactive Black 5	Silver-cobalt composite oxide 0.2–1 g L−1	Gas flow rate 30 L h−1, pH 2.2–12, initial dye concentration 100–1000 ppm	Up to 99% TOC removal	[72]
Alizarin Red S	activated carbon powder/c-Fe2O3 nano-composite 0.2–2 g L−1	Ozone dose 5 g h−1, pH 3–11, time 30 min, initial dye concentration 100–500 mg L−1	Up to 95% dye removal, 40% mineralization	[199]
Rinsing effluents containing Reactive Blue 19, Reactive Red 239, Reactive Yellow 176	MnFe2O4@CA 1 g L−1	Ozone concentration 20 mg L−1, gas flow rate 0.5 L min−1, pH 7	100% decolorization after 15 min, 65% COD removal after 40 min	[196]
Effluents after electrocoagulation containing mainly Reactive Black 5	Activated carbon 0.5 g L−1	Transferred ozone dose 500 mgO3 L−1, pH 11, time 30 min,	Above 90% decolorization, toxicity decrease	[75]
Textile wastewater	Copper-doped zinc oxide 1–4 g L−1	Ozone flow 10 to 40 g m−3, time 30 min, pH 3–11 (optimal 7)	Up to 90% COD removal	[176]
Peroxone
Crystal Violet	none	Ozone dose 2 mg L−1 min−1, pH 3–9 (optimal 9), time 30 min, initial dye concentration 25–200 mg L−1	100% decolorization	[79]
Direct Red 80	none	Ozone dose 1.25 g L−1 min−1, H2O2:O3 ratio equal to 1:10500, pH 2–13.5 (optimal 13), initial dye concentration 100 mg L−1	99% decolorization, 43% COD removal	[77]
Direct Black 22	none	Ozone dose 5 g h−1, pH 3–11 (optimal 11), time 30 min, 100 mg L−1 H2O2 addition	66% COD removal	[195]
Fenton Based
Methylene Blue	iron (II) sulphate 2–5 mM	10–80 mM H2O2, 20–40 °C, pH 2–7 (optimal 3), initial dye concentration 10–50 ppm, time 30 min	98.8% decolorization, 85% COD removal	[183]
Acid Yellow 17	iron (II) sulphate 0.04–0.07 mM	0.50–1.1 mM H2O2, 25 °C, pH 2–8 (optimal 3), initial dye concentration 0.06–0.09 mM, time 60 min	89% degradation	[184]
Acid Red 27	iron (II) sulphate 60–100 mg L−1	20–100 mgH2O2 L−1, pH 2–5 (optimal 3.5), time 30 min, initial dye concentration 100 mg L−1	72% COD removal	[192]
Ponceau Xylidine, calconcarboxylic acid	iron (II) sulphate 1.7 mM	7.3 mM H2O2 or Na2S2O8,	Decolorization: 94% (1 min), 100% (240 min), COD removal (240 min): 40% Fe/HP, 60% Fe/SPS	[95]
Methylene Blue	pulverized Malacantha alnifolia tree bark modified with iron (II) sulfate 0.5–1 g L−1	Fe2+/H2O2 ratios: 10/10,000–100/10,000, pH 2–8, time 60 min	97% dye removal	[96]
Acid Red 27	Zero valent iron 60–100 mg L−1	20–100 mgH2O2 L−1, pH 2–5 (optimal 3), time 30 min, initial dye concentration 100 mg L−1	69% COD removal, toxicity decrease	[192]
Crystal Violet	zerovalent iron nanoparticles dispersed on polyester fabrics 5 g L−1	20–100 mLH2O2 L−1 (optimal 100), pH 5–9 (optimal 5)	99% dye removal	[92]
Methyl Orange	iron (III) nanoparticles synthesised with Dimocarpus longan extract 0–18.5 mg L−1	0–46.8 mM H2O2, time 30 min, pH 2–10 (optimal 3), initial dye concentration 50–250 mg L−1	100% dye removal	[200]
Methylene Blue	iron (III) loaded on activated carbon (2–15 wt%)	Packed bed reactor, 0.0163–0.326 M H2O2, pH 2–9 (optimal 3.5), temperature 30–50 °C, initial dye concentration 100 mg L−1	70% dye removal	[94]
Eriochrome Black, Methylene Blue, Rhodamine B	core-shell nickel cobalt spinel coated with iron phthalocyanine 4–6 g L−1	40–60 mM H2O2, pH 4–6.7, initial dye concentration 5–20 mg L−1	100% dye removal, 90% TOC removal (Rhodamine B)	[93]
Orange II	calcium strontium copper loaded perovskite 1 g L−1	Without H2O2, time 90 min, initial dye concentration 10–100 ppm	95% degradation, 40% carbon removal	[188]
Methyl Orange	Perovskite 10–25 mg L−1	Without H2O2, pH 2–10 (optimal 2.5), time 20 min, initial dye concentration 20 ppm	90% degradation	[201]