Table 3.

Advanced oxidation process for SARS-CoV-2 pharmaceutical drugs removal

AOP	Pharmaceutical drug	Conditions	Efficiency/toxicity	By-product	Advantages and disadvantages
Photocatalysis	Lamivudine (An et al. 2011)	TiO2 = 1.0 g/L pH = 6.7 Lamivudine = 60 µM High-pressure mercury lamp (GGZ-125, Shanghai Yaming Lighting, Emax = 365 nm, 0.38 mW/cm2)	87.1%	m/z values: 246: monohydroxylated intermediates 262: dihydroxylated derivatives 136: photohole attack at N3, 112: photohole attack at N3, 129: oxidized by HO• 69: opening of aromatic ring	Advantages: Catalyst must be recovered Is effective to mineralize organic compounds High oxidation capacity Immobilizing the catalyst solve the recovery issues The process is stable Disadvantages: The bandgap of catalyst limits the use of solar irradiation Modification of catalyst increase the cost Poor capability for carrier charge separation
	Ivermectin (Havlíková et al. 2016)	TiO2 = 2 g/L UV Camag lamp (366 nm) Room temperature (25 °C) Aerobic conditions using a bubbling air pump, 5 h, pH 5	92.5%	DII1 ivermectin monosaccharide C41H62O11 (MW 730.4), m/z 741.3 and 633.3 DII2 ivermectin aglycone C34H50O8 (MW 586.4), m/z 608.8 and m/z 373.9 DII3 yielded the protonated ion [M + Ti]+ (m/z 649.1)
	Dexamethasone (Pazoki et al. 2016)	Ag coated TiO2 (1.5 g/L) 35 °C, pH = 3 Dexamethasone = 5 mg/L UV lamp 100 ≤ λ ≤ 280 nm, visible lamp 400 ≤ λ ≤ 700 nm	77.6% UV light irradiation 63.8%, VIS light irradiation	Mineralization of two carbon atoms, formation of a ketone group continued by the concerted losses of the HF molecule and of the H2O molecules
	Dexamethasone (Ghenaatgar et al. 2019)	Dexamethasone = 25 mg/L, catalyst dosage 500 mg/L. Catalyst: WO3 and ZrO2. Lamps: UVC (254 nm), UVA (365 nm), halogen (more than 380 nm)	180 min 81.16% UV/ZrO2 75.64% BLB/ZrO2 69.36% halogen/ZrO2 47% UV/WO3 100% BLB/WO3 (120 min) 100% halogen/WO3 (120 min)
	Azithromycin (Čizmić et al. 2019)	Nanostructured TiO2 film deposited on a borosilicate glass substrate UV-C lamp (254/185 nm) pH 10, 25 °C	k = 0.8 min−1 (ultrapure water) k = 0.9 min−1 (synthetic effluent) The formed degradation products are not toxic (Vibrio fischeri)	DP1 C15H31NO4 m/z 290 DP2 C16H33NO8 m/z 368 DP3 C22H43NO7 m/z 434 DP4 C30H58N2O9 m/z 592 DP5 C30H58N2O9 m/z 591
	Azithromycin (Kumar et al. 2021)	Ag@Bi4O5I2/SPION/Calg hybrid material 90 min under direct visible light (Xe lamp 300 W)	Ag@Bi4O5I2/SPION/Calg: 98.4% Bi4O5I2: 51.5%	P1 (via O-demetylation) P2 (m/z = 720) P4 (m/z = 593) L-cladinose ring P5 (m/z = 433) D-desosamine P8 (m/z = 177) loss of desosamine ring Cleavage of C-O bond further in P8 leads to ring opening of cladinose to form P9 (m/z = 121) and P10 (m/z = 85)
	Azithromycin (Naraginti et al. 2019)	ZrO2/Ag@TiO2 nanocomposite Visible light (250 W xenon lamp adjusted to 100 mW/cm2), 8 h 100 mg/50 mL (2 mg/mL) of catalyst	92% (20 mg/L) 52% (10 mg/L) 44% (5 mg/L) 18% (2.5 mg/L) Based on the E. coli growth, the effluent increased to 90.93 of detoxification efficiency, Using Vigna radiata, the germination index increased to 81.05% in effluent	TP-A and TP-B m/z 734.8 corresponds to O-demethylation or N-demethylation TP-C m/z 704.8 TP-D m/z 692.4 TP-E m/z 720.9 (simultaneous O-demethylation and N-demethylation) TP-K m/z 156.2 (dehydrated product of D-desosamine) TP-L m/z 114.2 (loss of N-methylenemethanamine fragment) TP-M m/z 121.1 TP-N m/z 85.3
	Azithromycin (Sayadi et al. 2019)	GO@Fe3O4/ZnO/SnO2 Batch system: pH = 3, 120 min, azithromycin: 30 mg/L and 1 g/L of catalyst, UV-C lamp Continuous system: bed height (6. 8 and 10 cm), flow rate (6 mL/min) and 30 mg/L	90.06% (batch) Column breakthrough point 5 min (6 cm) 8 min (8 cm) 14 min (10 cm)
	Ciprofloxacin (Alhokbany et al. 2020)	Chitosan based nanocomposite (g-C3N4/Ag3PO4/CS) 60 min, room temperature, neutral medium, 2 mg of catalyst, ciprofloxacin = 20 mg/L	90.43% 79.43% after six cycles	Decarboxylation of intermediate (I) produced intermediate (II) m/z 306.1 Then, intermediate (III) m/z 262.1 are produced. The cyclopropyl group form the quinolone ring produced intermediate (IV) with m/z 222.1, which was converted in to intermediate (V) with m/z 243.1 which are converted after decarboxylation and ring closing in to five member ring intermediate (VI), this produce the intermediate (VII) which are destroyed and produced the intermediate (V)
	Acyclovir (An et al. 2015)	25 °C, pH = 6.37, 2.0 mW/cm2 light intensity light source, Acyclovir = 50 µM, 0.5 g/L TiO2	Degradation 100% Mineralization 80% More toxic products were produced during the photocatalytic degradation of acyclovir	Acyclovir m/z 226 m/z = 242 (monohydroxylated acyclovir) m/z = 258 (dihydroxylated acyvlovir) m/z = 186 m/z = 204 m/z = 158 m/z = 152 (guanine)
	Tinidazole (Acosta-Rangel et al. 2018)	Iron-doped silica xerogels (1 g/L), Tinidazole = 25 mg/L, pH 7, 25 °C, 1 h, solar irradiation	98.38% HEK-293 cell viability was > 75%, indicating that neither tinidazole nor its byproducts have toxic effects on this type of cell	P1 178 g/mol P2 140 g/mol P3 137 g/mol P4 236.28 g/mol
	Sertraline (Rejek and Grzechulska-Damszel 2018)	TiO2 (1.15 g/L), sertraline = 0.1 g/L, mercury lamp	91%
	Hydroxychloroquine (Da Silva et al. 2021)	Hydroxychloquine = 10 m/L; catalyst dose: 2 g/L, pH = 7.5; UV-A radiation (0.061 W/m2)	96% Lactuca sativa and Artemia salina confirmed the reduction of effluent toxicity after treatment
Fenton	Citralopram (Hörsing et al. 2012)	Molar ratio Fe2+/H2O2 1/10, the concentrations of Fe2+ varied from 0.0003 to 12.5 mM, pH 3, initial concentration 100 µg/L	90%	Citralopram is demethylated into Di-desmethylcitalopram. The second breakdown pathway also mimics the human metabolism and gives rise to formation of citalopram-N-oxide	Advantages: Highly oxidative capacity Disadvantages: Narrow working pH range, High costs Risks associated with handling, transportation and storage of reagents (H2O2 and homogeneous solution of iron ions) Significant iron sludge related second pollution
Electro-Fenton	Sertraline (Rachidi et al. 2021)	Sertraline = 0.01 mM, 4 h, carbon–carbon-lorraine felt as cathode and Pt foil as anode, 0.05 M of Na2SO4, 0.1 mM Fe2+, pH 3, 400 mA	99% COD BOD5/COD ratio increased from 0.47 to 3		Advantages: The on-site production of H2O2 avoid the risks related to its transport, storage, and handling The continuous regeneration of Fe2+ on the cathode minimize the iron sludge production and improve the degradation efficiency Disadvantages: Low H2O2 yield Low unit cell body throughput Low current density and low conductivity EF-Feox: High consumption of anode and large amount of iron sludge production
	Chloroquine (Midassi et al. 2020)	Current density up to 60 mA/cm2, O2 flow rate up to 80 mL/min, pH 3.0 Electro-Fenton BDD or Pt systems	Electro-Fenton BDD 92% TOC Electro-Fenton Pt 84% TOC Electrolysis BDD 68% TOC Electrolysis Pt 17% TOC	7-chloro-4-quinolinamine Oxamic acid Oxalic acid
Photo electro-Fenton	Fluoxetine (Manrique et al. 2019)	700 kJ/L m2, IrO2/ RuO2 as anode, 20-30A, 0,05 mol/L Na2SO4, 18 μM de Fe2+, fluoxetine = 40 mg/L, neutral pH	70% 11% mineralization Degradation by-products do not increase or sustain toxicity		Advantages: Higher degradation and mineralization rate Great UV input pH intervals between 2 and 4 Photolysis of by-products enhancing the mineralization processes Disadvantages: High cost related to electrodes and UV lamps Low energy consumption
Fenton-like	Fluconazole ( Zhang et al. 2020a, b)	Cu-V bimetallic Catalyst, pH 6	15% H2O2 82% CuOx/H2O2 100% CuVOx/H2O2		Advantages: The metal-catalyst work over a broader pH The surface chemistry influences the H2O2 dissociation and HO● production The introduction of other transition metals improves the surface characteristics Metal ion doping improve the adsorption and catalytic performance Disadvantages Relative high cost (compared to conventional Fenton) Presence of transition metals on the effluent
	Fluconazole ( Zhang et al. 2020a, b)	Cu-Ce bimetallic catalysts, (0.1 g/L), fluconazole = 20 mg/L, H2O2 = 50 mM, pH = 5.0, at room temperature	94%
Fenton-like combined with coagulation	Azithromycin (Yazdanbakhsh et al. 2014)	Coagulation process Poly aluminum chloride (PAX-18), 100 mg/L and pH 7.0 Fenton-like process: Fe0 = 0.36 mM/L H2O2 = 0.38 mM/L pH = 7.0	Coagulation 82.14% COD Combined treatment: 96.89% COD		Advantages: Combined processes enhance the COD removal
Photo-Fenton	Lamivudine (Lucena et al. 2020)	Three UV-C lamps, 60 min, pH 5–6 Lamivudine: 30 mg/L Fe = 120 mg/L H2O2 = 600 mg/L (fractional addition at 0, 10 and 20 min)	62.34%		Advantages Accelerate the reduction of Fe3+ to Fe2+ Reduce the iron sludge production and the initial Fe2+ concentration Enhance the oxidation ability and the degradation efficiency of organic pollutants Higher degradation rate Decrease sludge volume generation Disadvantages Low utilization rate of light energy High operation costs Design of photoreactor Short operating lifecycle of artificial UV sources High energy consumption Variability and limited availability of solar radiation Wasting of oxidants (due to the radical-scavenging effect of H2O2 and its self decomposition) Formation of solid sludge Production of high amounts of anions in the effluent
	Amoxicilin (Elmolla and Chaudhuri 2010)	Amoxicilin = 104 mg/L, pH3, UV-A (365 nm) = 6 W, H2O2/Fe2+  = 20, 50 min	100% 58.4% mineralization
	Tinidazole (Velo-Gala et al. 2017)	120 min	45.20% (photolysis UVC) 49.80% (photolysis solar) 100% H2O2/UVC 59.59% H2O2/solar 100% (photo-Fenton UVC) 100% (solar photo-Fenton)
	Fluoxetine (Manrique Losada, Quimbaya Ñañez, and Torres Palma 2019)	90 μM de Fe2+, 1000 μM de H2O2 835 kJ/Lm2 (acidic pH) 1.269 kJ/Lm2 (neutral pH)	80% Acid pH 73% Neutral pH 44% mineralization Degradation by-products do not increase or sustain toxicity
Heterogeneous photo-Fenton	Chloroquine phosphate (Wang et al. 2022)	pH 5, 2D micron-sized MOF (metal organic frameworks) sheet (BUC-21(Fe),	21% under UV light 43.9% H2O2 + UV light 48.9% BUC-21(Fe) + H2O2 100% BUC-21(Fe) + H2O2 + UV light (365 nm) The toxicity of oxidation products was significant declined to not harmful	B m/z = 322 C m/z = 340 D m/z = 114 E m/z = 159	Advantages: Low iron ions leaching Efficient cycling of Fe3+ and Fe2+ Low iron sludge production Wide working pH range Reusability and long-term stability of catalysts Disadvantages Complicated synthesis routes High synthesis costs of catalysts Design of heterogeneous Fenton reactor
Sono-Fenton	Dexamethasone (Hasan Rahmani et al. 2015)	pH: 4, nano Fe0: 0.3 g/L, H2O2: 1.5 mmol, initial concentration: 15 mg/L and US: 140 kHz	92%		Advantages: Enhances the HO● production Another reactive radical are produced Low Fe requirement
EO PEO SEO	Hydroxychloroquine (Bensalah et al. 2020)	Electrochemical oxidation using BDD and its combination with UV irradiation and sonication 20 mA/cm2, pH 7.1, 25 °C,	EO = 100% (300 min) PEO = 100% (180 min) SEO = 100% (60 min)	EO: 7-chloro-4-quinolinamine (CQLA) Oxalic acid Oxamic acid Chloride, nitrate, and ammonium	Advantages Avoid the sludge generation and the need for sludge final disposal methods and the involved environmental impact Good quality of the treated wastewater Sustainability (use of only electrons as reagents) no another chemical, high degradation and mineralization efficiency ease of automation for small-scale Disadvantages: High cost Potentiality to be scaled up for large applications The degradation efficiency is affected by the low rate of diffusion
EO PEO	Dexamethasone (Grilla et al. 2021)	BDD as anode and a stainless steel or carbon cloth cathode For simulated solar light experiments, a solar simulator equipped with a 100 W xenon, O3-free lamp was employed	90% (45 min at 0.2 A/m2, 5 mg/L)) 92% ± 2% (0.25–1 mg/L, 0.2 A/m2) 95% (electrochemical oxidation, persulfate addition and simulated solar light irradiation	Dexamethasone C22H30O5F TP1 C22H30O6F TP2 C22H28O7F TP3 C21H28O6F TP4 C21H30O7F TP5 C20H22O3F TP6 C20H22O2F TP7 C16 H18O2F
EO	Abacavir (Zhou et al. 2019)	Penetration flux porous Ti/SnO2–Sb anode, 10 min at a j = 0.2 mA/cm2	97% 53.3% TOC (5 h, 5 mA/cm2) Abacavir showed chronic toxicity to fish, TP150 show the lowest toxicity	TP318 produced by the oxidation of the cyclopropylamine moiety TP246 formed from the cleavage of the cyclopropyl ring TP150 generated via the further degradation of the TP318 and TP246
EO	Lamivudine (Y. Wang et al. 2019a, b)	Ti/SnO2-Sb/Ce-PbO2 anode, 20 mM Na2SO4, j ≥ 10 mA/cm2	97.7% 14 mA/cm2 95.7% pH 5 98.3% 2.5 mg/L	Lamivudine (P229) Intermediates: P245, P111, S119, P135
UV/H2O2	Lamivudine (Lucena et al. 2020)	Three UV-C lamps (30 W and photons emissions of 1,98 × 10−3 W‧cm2) 180 min, pH 5–6 H2O2 = 600 mg/L [Lamivudine] = 5 mg/L	97.33% The compounds formed after the treatment present toxicity to Lactuca sativa		Advantages: The process takes place at room temperature, without sludge generation, easy handling, high stability, and present high removal rates of chemical oxygen demand chemical‐free treatment that requires relatively low maintenance and operational costs Disadvantages: The mineralization rate is affected if the H2O2 dosage in the solution is low
	Ciprofloxacin (Guo et al. 2013)	pH 7, H2O2 = 5 mM, 17-W low-pressure mercury lamp emitting at 254 nm, 25 °C, ciprofloxacin = 10 mg/L	K = 3.72 ± 0.24 × 10−3/s Toxicity of products assessed by Vibrio qinghaiensis demonstrated that UV/H2O2 process was more capable on controlling the toxicity of intermediates in CIP degradation than UV process	17 by-products keto-derivative are transformed to produce two products through hydroxyl group addition or amidation. Desethylene ciprofloxacin reveals further oxidation at the piperazinyl ring Compound 7 loss of the cyclopropyl group (2C and 2H atoms) followed by introducing a hydroxyl group and CH2 or losing a carboxyl group
	Acyclovir (Russo et al. 2017)	UV254 nm (4.7 mW/cm2), [H2O2]o/[acyclovir]o = 20, pH = 6	k = 2.30 ± 0.11 × 109 1/M s The inhibition of Vibrio fischeri luminescence remained unchanged in the presence of UV254/H2O2 irradiated solutions, in comparison to the untreated solution	Formation of hydroxylated imidazole-based compounds or species formed by the fragmentation of the pyrimidine ring
	Azithromycin (Cano et al. 2020)	pH 9, 482 mg/L H2O2, 500 W/m2 irradiance	80.0%
UV/H2O2 and moving-bed biofilm reactor	Azithromycin (Shokri et al. 2019)	Azithromycin = 2 mg/L, 254 nm: 12 h	91.2%		Advantages: MBBR have the ability to accumulate biomass and biofilm allow a large number of microorganisms
UV/chlorine	Fluconazole (Cai et al. 2020)	λ = 254 nm, pH 7, initial concentration of free available chlorine 100 μM, 25 ± 1 ℃	16.5% chlorine 62.1% UV photolysis 90.6% chlorine + UV Most of transformation products had lower toxicity than fluconazole	TP 305 TP 287 TP 303 TP 285 1 M 83 TP 151	Advantages: UV photolysis of HClO and ClO− generate HO● and Cl● Cl● degrade contaminants Disadvantages: Possible harmful by-products
Ultrasound	Azithromycin (Muñoz-Calderón et al. 2020)	Ultrasound (40 kHz), 50 W, pH 9, 60 min, azithromycin = 1.0 mg/L	46.15%		Advantages Safety, cleanliness, energy conservation, and no or minimal secondary pollution products not using chemicals to generate highly oxidizing species and not generating harmful products Disadvantages long time High cost lower degradation rate can result if the dose and size of catalyst are below or higher than the optimum difficulty of large scale and the low selectivity of the radicals generated
	Azithromycin (Yazdani and Sayadi 2018)	ZnO nanoparticles, pH 3, 40 °C, 15 min, 1 g/L of catalyst, 50 mg/L of H2O2, azithromycin = 20 mg/L, 35 kHz	98.4%
	Sulfamethoxazole (Al-Hamadani et al. 2016)	Glass beads and single-walled carbon nanotubes (45 mg/L) as catalyst	pH 7, power of 0.18 W/L, 15 °C: 72% (1000 kHz,) 33% (28 kHz) Glass beads and single-walled carbon nanotubes, 60 min: 88% (28 kHz) 97% (1000 kHz)
	Tinidazole (Rahmani et al. 2014)	pH 3, 120 kHz frequency, 333 mM/L of H2O2 and 150 min of operating time	75% ultrasound/H2O2 8.5% ultrasound	Free of hazardous intermediate(s)
Ultrasound combined with biological treatment	Fluoxetine (Serna-Galvis et al. 2015)	600 kHz, 20 °C	20% TOC (240 min) 70% TOC (360 min)		Advantages A combined system, transforms the recalcitrant pharmaceutical into biodegradable compounds that are treatable in a conventional biological system, without previous adaptation and/or optimization
O3/Fenton	Amoxicilin (Li et al. 2015)	Amoxicilin = 100 mg/L, Fe2+  = 0.6 mM, 800 rpm, T = 25 °C, pH = 3, Oxygen flow = 150 L/h, 120 min	100% degradation 65% mineralization	S1 C16H17N3O7S S2 C16H19N3O8S S3 C14H21N3O6S S4 C8H14N2O4S S5 C8H7N1O6 S6 C3H6N2O4S S7 C4H10O S8 C3H4O2 S9 CH6NS S11 C15H19N3O3S S12 C15H21N3O4 S13 C14H23N3O4 S14 C14H21N3O6	Advantages: Synergetic effect accelerate Fenton reagents to enhance HO● generation which leads to higher oxidation rates
Ozonation	Acyclovir (Prasse et al. 2012)	O3 generator 300, Fischer Technology, Germany	Using Vibrio fischeri, carboxyacyclovir revealed no toxic effects	m/z 274 m/z 198 m/z 170 m/z 153	Advantages: The volume of effluent remains constant along the process and sludge is not formed Installations require only a little space, O3 is generated in situ, so that no stock chemical solutions are needed Can be applied even if the effluent fluctuates both in terms of flow rate and/or composition O3 remnants can be eliminated as ozone tends to decompose into oxygen Disadvantages: is unstable and can quickly decompose into molecular oxygen alone does not cause complete oxidation of some refractory organic compounds, low reaction rate High cost of equipment and maintenance High requirements of energy
	Oseltamivir acid (Mestankova et al. 2012)	[Oseltamivir] = 25 mM (buffered to pH 7) and 10 mM t-butanol ( HO• scavenger)	K = 1.7 105 M−1 s−1
O3/H2O2	Sulfamethoxazole (Gomes et al. 2018)	O3 = 0.42 mM H2O2 = 5 mM 45 min	~ 100% by-products formed have a higher acute toxicity than the Sulfamethoxazole
Photocatalytic ozonation O3/UVA/TiO2	Ciprofloxacin (Asgari et al. 2021)	O3 0.34 g/h and catalyst doses of 1.0 g/L during 15 min reaction time at pH 9.0, λ = 365 nm	98.5% (15 min, first cycle) 81.1% of TOC (60 min) 93.4% (in the sixth cycle		Advantages Free electrons of the semiconductor can interact with ozone molecules forming ozonide radicals
Photocatalytic ozonation	Amoxicilin (Moreira et al. 2015)	Amoxicilin = 0.1 mM, TiO2 (0.5 g/L), natural pH, O3 Flow 150 Ncm3/min, UV–Vis > 300 nm	100% TOC in 30 min	By-products not inhibit the growth of S. aureus and E. coli
Catalytic ozonation process	Dexamethasone (G. Asgari et al. 2020)	Al2O3 nanoparticles (0.5 g/L, pH 10, dexamethasone = 10 mg/L, 12 min	100%		Advantages: Catalyst promote the ozonation of organics by oxidation–reduction reaction
Biological treatment coupled with ozonation	Sulfamethoxazole (Knopp et al. 2016)	0.87 ± 0.29 g O3 at hydraulic retention time: 17 ± 3 min	98%		Advantages Sludge reduction and removal of recalcitrant organic contaminants from wastewater Oxidation avoiding the harmful by-products
Biological treatment, sand filtration and ozonation	Carbamazepine Azithromycin Sulfamethoxazole (Nakada et al. 2007)	Activated sludge 9 h of retention time O3 = 3 mg/L during 27 min	Carbamazepine 43.3% via activated sludge, 22.4% via sand filtration 8.25% via ozonation, azithromycin 92.6% via ozonation, sulfamethoxazole 61.5% via activated sludge, 26.9% via sand filtration 92.6% via ozonation
O3/PMS	Rivabirin ( Liu et al. 2021a, b)	10 μM ribavirin solution under ambient temperature (25 °C), and the pH of solution was buffered with 5 mM phosphate	5% PMS K = 3.84 × 10−2 O3 K = 4.32 × 10−1 O3/PMS	Rivabirin m/z 245 TP-1 m/z 241 TP-2 m/z 211 TP-3 m/z 198 TP-4 m/z 149	Advantages: The system d simultaneously produce HO• and SO4•− PMS enhance ozonation Disadvantages: Toxic by-products
Photocatalysis-activated sulfate radical	Chloroquine phosphate (Yi et al. 2021)	Catalyst: 34,910-pyrenetetracarboxydiimine (PDINH)/ MIL-88A composite 30 min, irradiation of 300 ± 50 mW LED visible light, PDS, Chloroquine = 10 mg/L	94.6% Toxicity Estimation Software (T.E.S.T.) The LD50 was 3.07 mg/L for chloroquine, by-products D and C showed lower LC50 value, even the product D was “very toxic” By-products B, C, E, J, K, L, M and Q were even considered as “developmental non-toxicant”	Chloroquine (A) m/z = 320 By-products: B m/z = 292 C m/z = 264 D m/z = 247 E m/z = 159 F m/z = 179 G m/z = 164 H m/z = 142 I m/z = 114 J m/z = 158 K m/z = 102 L m/z = 159 M m/z = 118	Advantages: The active species are HO•, SO4•−, •O2− and h+ High degradation rate of organic pollutants The yield of photogenerated charge carriers is constant High activity and selectivity for removing organic pollutants Higher pH favors the non-radical activation Disadvantages: High cost and difficult acquisition for a large-scale applications
	Dexamethasone (Shookohi et al. 2019)	Persulfate dose = 0.1 mM, Dexamethasone = 20 mg/L and Al2O3 dose = 0.05 g/L	88% pH 3 52% pH 11 94% (0.5 mM persulfate) 66% (without Al2O3)
	Ciprofloxacin (Zhang et al. 2021)	CuO-LDH composite (0.25 g/L) 30 min, pH 4–10, Ciprofloxacin = 10 mg/L, oxidant = 1 mM	14.4% (LDH) 94.4% (Cu4-LDH)	P1 m/z 334 P2 m/z 306 P3 m/z 300 P4 m/z 263 P5 m/z 205
	Ciprofloxacin (Zou et al. 2019)	Magnetic nitrogen-doped microalgaederived carbon (Fe–N@MC) (0.2 g/L), ciprofloxacin 10 mg/L, 1 mM PMS, 120 min	92.6%	Ciprofloxacin m/z 330 Pathway 1: m/z 362, m/z 334, m/z 316, m/z 306, m/z 291, m/z 263, m/z 245 Pathway 2: m/z 330, m/z, 286 Pathway 3: m/z 348, m/z 362, m/z 334
	Ciprofloxacin (Shah et al. 2019)	ciprofloxacin = 10 mg/L, Mn0 = 1.0 g/L, and S2O82−  = 50 mg/L, 80 min	95% The ecotoxicity were estimated from the acute and chronic toxicities towards aquatic organisms, the final product to be nontoxic	NH4+, F–, NO2–, NO3–, and CH3COO–
Photo-Fenton-like (sulfate radical)	Ciprofloxacin (A. Wang et al. 2019a, b)	P2-Mn3O4 (0.1 g/L), 10 min, ciprofloxacin = 15 µM 1 mM PMS	79.4%	Pathway 1: m/z 334, m/z 306 and m/z 263 Pathway 2: m/z 362, m/z 334 and m/z 256 Pathway 3: m/z 346, m/z 362 and m/z 334	Advantages: Cost-effective and environment friendly Higher standard redox potential Better selectivity, longer half-life Wider range of pH Lower toxicity
	Chloroquine phosphate (Peng et al. 2022)	(SA Co–N-C(30), 30 min, PMS	97.5%	The single atom Co in the structure served as the active sites for pollutant degradation