Magnetic Fe3O4-N-doped carbon sphere composite for tetracycline degradation by enhancing catalytic activity for peroxymonosulfate: A dominant non-radical mechanism

Mechanistic insights of PO43- functionalized carbon nitride homojunction hydrogels in photocatalytic-self-Fenton-peroxymonosulfate system for tetracycline degradation

In this study, metal-free PO43- enriched g-C3N4/g-C3N4 (PGCN) homojunction alginate 3D beads were developed for in-situ H2O2 production under visible light. Later, the photocatalytic-self-Fenton system was integrated with peroxymonosulfate for tetracycline degradation. Initially, the PO43- enriched g-C3N4 (PCN) and a homojunction composed of PCN and g-C3N4 (GCN) were prepared via the wet-impregnation method. Later, PGCN homojunction was formulated into 3D alginate beads through the blend-crosslinking method. The comprehensive characterization of the homojunction beads affirmed the closer contact between the semiconductors, alteration of the bandgap, faster channelization of electron-hole pairs, and improved separation of charge carriers that attributed to higher catalytic efficacy. The PGCN beads exhibited a maximum H2O2 production of 535 ± 12 µM under visible light irradiation for 60 min. The homojunction hydrogels displayed 99 ± 0.25 % tetracycline degradation in 20 min in the photocatalytic-self-Fenton-PMS system. The experimental studies also claimed a maximum chemical oxygen demand removal of 81 ± 3.6 % in 20 min with maximum reusability of beads up to 20 cycles. The Z-scheme electron migration mechanism is proposed based on the results aided by scavenger and electron spin resonance analysis. Overall, the as-synthesized alginate-supported homojunction-based photocatalytic-self-Fenton-peroxymonosulfate system is highly versatile and reusable for energy and environmental remediation.

Activation of persulfate with magnetic Fe3O4-municipal solid waste incineration bottom ash-derived zeolite core-shell materials for tetracycline hydrochloride degradation

A novel and environmentally friendly magnetic iron zeolite (MIZ) core-shell were successfully fabricated using municipal solid waste incineration bottom ash-derived zeolite (MWZ) coated with Fe3O4 and innovatively investigated as a heterogeneous persulfate (PS) catalyst. The morphology and structure composition of as-prepared catalysts were characterised, and it was proved that the core-shell structure of MIZ was successfully synthesised by coating Fe3O4 uniformly on the MWZ surface. The tetracycline hydrochloride (TCH) degradation experiment indicate that the optimum equimolar amount of iron precursors was 3 mmol (MIZ-3). Compared with other systems, MIZ-3 possessed a superior catalytic performance, and the degradation efficiency of TCH (50 mg·L-1) in the MIZ-3/PS system reached 87.3%. The effects of reaction parameters on the catalytic activity of MIZ-3, including pH, initial concentration of TCH, temperature, the dosage of catalyst, and Na2S2O8, were assessed. The catalyst had high stability according to three recycling experiments and the leaching test of iron ions. Furthermore, the working mechanism of the MIZ-3/PS system to TCH was discussed. The electron spin resonance (ESR) results demonstrated that the reactive radicals generated in the MIZ-3/PS system were sulphate radical (S O 4 - ∙ ) and hydroxyl radical (•OH). This work provided a novel strategy for TCH degradation under PS with a broad perspective on the fabrication of non-toxic and low-cost catalysts in practical wastewater treatment.

Zn-Doped MnCO3/CS Composite Photocatalyst for Visible-Light-Driven Decomposition of Organic Pollutants

Zn-doped MnCO3/carbon sphere (Zn-doped MnCO3/CS) composites were synthesized using a simple hydrothermal procedure. Among various samples (ZM-50, ZM-05, and ZMC-0), the ternary Zn-doped MnCO3/CS (ZMC-2) catalyst demonstrated excellent visible light-induced photocatalytic activity. This improvement comes from the Zn addition and the conductive CS, which facilitate electron movement and charge transport. The catalyst exhibited efficient degradation of methylene blue (MB) over a wide pH range, achieving a removal efficiency of 99.6% under visible light. Radical trapping experiments suggested that •OH and •O2- played essential roles in the mechanism of organic pollutant degradation. Moreover, the catalyst maintained good degradation performance after five cycles. This study offers valuable perspectives into the fabrication of carbon-based composites with promising photocatalytic activity.

Starch of oat derived nanostructured Fe/Mn bimetallic carbon materials for sulfamethoxazole degradation via peroxymonosulfate activation

Fe/Mn bimetallic carbon materials were synthesized by combining oat and urea, followed by and carbonization processes, the activity and mechanism of the obtained materials in activating peroxymonosulfate (PMS) for sulfamethoxazole (SMX) degradation were determined. Data suggested that the obtained material (CN@FeMn-10-800) showed the optimal performance for SMX degradation under the1:8:0.05:0.05 mass ratios of oat/urea/Fe/Mn. Around 91.2 % SMX (10 mg L-1) was removed under the conditions of 0.15 g L-1 CN@FeMn-10-800 and 0.20 g L-1 PMS. The CN@FeMn-10-800 showed great adaptability under different conditions, satisfactory activation repeatability and versatility. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) demonstrated that core-shell structure with rich porous of CN@FeMn-10-800 was achieved. Quenching test and electron paramagnetic resonance (EPR) indicated that surface bound oxygen and singlet oxygen (1O2) were the dominate reactive groups in this system. X-ray photoelectron spectroscopy (XPS) suggested that graphite N, Fe0, Fe3C and Mn(II) were the dominant active sites. Through the work, a simple strategy could be found to make high-value use of biomass and use it to effectively purified wastewater.

Synergistic enhanced activation of peroxymonosulfate by heterojunction Co3O4-CuO@CN for removal of oxytetracycline: Performance, mechanism, and stability

Metal-organic frameworks (MOFs) as precursors for catalysts has drawn growing attentions. In this study, heterojunction Co3O4-CuO doped carbon materials (noted as Co3O4-CuO@CN) were prepared by direct carbonization of CuCo-MOF in air. It was found that the Co3O4-CuO@CN-2 exhibited excellent catalytic activity with the highest Oxytetracycline (OTC) degradation rate of 0.0902 min-1 at 50 mg/L of Co3O4-CuO@CN-2 dosage, 2.0 mM of PMS and 20 mg/L of OTC, which was 4.25 and 4.96 times that of CuO@CN and Co3O4@CN, respectively. Furthermore, Co3O4-CuO@CN-2 was efficient over a wide pH range (pH 1.9-8.4), and possessed good stability and reusability without OTC degradation decrease after five consecutive uses at pH 7.0. In a comprehensive analysis, the rapid regeneration of Cu(II) and Co(II) is responsible for their excellent catalytic performance, and the p-p heterojunction structure formed between Co3O4 and CuO acts as an intermediary of electron transfer to accelerate PMS decomposition. Moreover, it was interesting to find that Cu rather than Co species played a vital role in the PMS activation. The quenching experiments and electron paramagnetic resonance demonstrated that .OH, SO4•-, and 1O2 were the reactive species responsible for oxidation of OTC and the non-radical pathway triggered by 1O2 was dominant.

A co-precipitation route for the preparation of eco-friendly Cu-Al-layered double hydroxides with efficient tetracycline degradation

The construction of novel efficient catalysts for the treatment of organic pollutants in the aqueous environment is essential. The lamellar-like Cu-Al layered double hydroxides (CuAl-LDHs) with various mole ratios were synthesized by a simple route of co-precipitation, and the corresponding degradation characteristic was tested for the removal of tetracycline (TC) using PMS activation. The degradation efficiency of TC over CuAl-LDHs increased up to 93% within 10 min for the Cu/Al mole ratio of 3:1 and almost not changed at a higher mole ratio. For further calcining the optimal catalyst at 300 ℃, the degradation efficiency of TC was found to be increased to 96%. Sulfuric radicals and singlet oxygen were analyzed to be the main reason for the change in degradation characteristics, which was proved by radical quenching experiments and electron paramagnetic resonance technique. The parameters including PMS concentration, catalyst dosage, and reaction temperature on the TC degradation as well as the degradation mechanism for PMS activation were elaborated. The best proportion of CuAl-LDHs owned splendid stability and catalytic activity after reusing, which showed enormous potential in practical application.

Nitrogen doped magnetic porous carbon derived from starch of oatmeal for efficient activation peroxymonosulfate to degradation sulfadiazine

Nitrogen doped magnetic porous carbon catalyst based on starch of oatmeal was obtained by mixing and pyrolysis process, and its catalytic activity of peroxymonosulfate activation for sulfadiazine degradation was evaluated. When ratio of oatmeal/urea/iron was 1: 2: 0.1, CN@Fe-10 had the best catalytic activity to degrade sulfadiazine. Around 97.8 % removal of 20 mg L^-1 sulfadiazine was achieved under incorporating of 0.05 g L^-1 catalyst and 0.20 g L^-1 peroxymonosulfate. Good adaptability, stability and universality of CN@Fe-10 were verified under different conditions. Electron paramagnetic resonance and radical quenching test suggested that surface-bound reactive oxides species and singlet oxygen were the main reactive oxides species in this reaction. Electrochemical analysis indicated that CN@Fe-10 had a good electrical conductivity and electron transferred did occur among CN@Fe-10 surface, peroxymonosulfate and sulfadiazine. X-ray photoelectron spectroscopy suggested that Fe⁰, Fe₃C, pyridine nitrogen and graphite nitrogen were the potential active sites for peroxymonosulfate activation. Therefore, the work provided a practical approach for recycling biomass.

Ultra-small Co3O4 particles embedded into N-doped carbon derived from ZIF-9 via half-pyrolysis for activating peroxymonosulfate to degrade sulfamethoxazole

The fabrication of novel and efficient transition metal-based catalysts for peroxymonosulfate (PMS) activation is of great significance for environmental remediation. Concerning energy consumption, the Co3O4@N-doped carbon (Co3O4@NC-350) was constructed via a half-pyrolysis strategy. The relatively low calcination temperature (350 °C) caused Co3O4@NC-350 to exhibit ultra-small Co3O4 nanoparticles, rich functional groups, uniform morphology, and a large surface area. For PMS activation, Co3O4@NC-350 could degrade 97% of sulfamethoxazole (SMX) in 5 min with a high k value of 0.73364 min-1, which was superior to the ZIF-9 precursor and other derived materials. Besides, Co3O4@NC-350 could be re-used over 5 times without obvious performance and structure change. The investigation of the influencing factors containing co-existing ions and organic matter demonstrated the Co3O4@NC-350/PMS system has satisfactory resistance. The quenching experiments and electron paramagnetic resonance (EPR) tests showed ˙OH, SO4˙-, ˙O2 - and 1O2 participated in the degradation process. Moreover, the structure and toxicity of intermediates during the SMX decomposing process have been evaluated. Overall, this research provides new prospects for exploring efficient and recycled MOF-based catalysts for PMS activation.

Degradation of tetracycline antibiotic utilizing light driven-activated oxone in the presence of g-C3N4/ZnFe LDH binary heterojunction nanocomposite

In the present study, a binary heterojunction nanocomposite composed of graphitic carbon nitride (g-C₃N₄) and Zn/Fe-contained layered double hydroxide (ZnFe LDH) was employed as heterogeneous catalyst for the decomposition of tetracycline (TC) antibiotic utilizing Oxone and UV light irradiation. The sole use of g-C₃N₄/ZnFe LDH as adsorbent led to the negligible elimination of TC. In addition, the sole use of Oxone or UV (photolysis) and even their combination were not effective enough to degrade the target pollutant, while the combined process of g-C₃N₄/ZnFe LDH/Oxone/photolysis revealed significantly enhanced (synergistic) degradation of TC (92.4% within 30 min). Indirect detection tests for the identification of free radical species indicated the major role of both hydroxyl (^•OH) and sulfate (SO₄^•-) radicals in the degradation of TC by the g-C₃N₄/ZnFe LDH/Oxone/photolysis system. The elimination of TC followed a pseudo-first order kinetic model. The complete degradation of TC (degradation efficiency of 100%) was achieved within the reaction time of 25 min when ultrasound (US) was applied as enhancing agent. Furthermore, the results of total organic carbon (TOC) analysis were used to exhibit progress in the mineralization of the pollutant. The bioassay results indicated the decreased toxicity of the process effluent toward microbial population of Escherichia coli after the treatment.

Activation of Persulfate for Degrading Tetracycline Using the Leaching Residues of the Lead-Zinc Flotation Tailing

Inappropriate disposal of leaching residues from the lead-zinc tailings recovery process may result in environmental pollution. Its recycling and reuse remain a prevalent topic in environmental science and technology. It was roasted to prepare leaching residues-based materials (TLRS) in this work, and the TLRS were creatively used as the catalyst to active sodium persulfate (PS) to degrade organic pollutants. Degradation of tetracycline using the TLRS–PS system was evaluated, and the treating parameters were optimized. Roasting resulted in the exposure of active sites on TLRS surface, in which transition metals can donate electrons to PS to form SO₄^·−. SO₄^·− can further react with OH⁻ to form ·OH. Formation of these radicals was confirmed by both quenching experiments and EPR analysis. Under optimized conditions, 85% of the TC can be degraded in 3.0 h, and ~50% of degraded TC was mineralized to CO₂ and H₂O. The performance of TLRS barely changed after four reuses, suggesting the chemical stability of TLRS. The presence of dissolved substance in the water matrix could weaken the performance of the TLRS–PS system. A mechanism of TC degradation was proposed based on the experimental results and literature. These preliminary results provide us new insight on the reuse of lead-zinc flotation tailings.

Durable and eco-friendly peroxymonosulfate activation over cobalt/tin oxides-based heterostructures for antibiotics removal: Insight to mechanism, degradation pathway

Potential leaching of Co ions could decrease the catalytic activity and cause secondary pollution of water, thereby threatening ecological safety and human health. In response, the in-situ generation of well-dispersed Co₂SnO₄ and SnO₂ with fine interfacial feature was constructed for PMS activation toward efficient tetracycline degradation and lower cobalt ion leaching feature. The synergistic effect of Co₂SnO₄ and SnO₂ endowed Co₂SnO₄-SnO₂ an outstanding catalytic performance for tetracycline degradation in alkaline condition. Meanwhile, the catalysts can effectively degrade the quinolones, dyes and mixture pollutant solution. The excellent performance can attributed to the in-situ introduction of SnO₂, which stabilizes the microstructure and provides an effective electronic pathway to enhance the activity of Co₂SnO₄ in the Co₂SnO₄-SnO₂. In optimized condition, the tetracycline degradation efficiency was enhanced to 94.9% within 20 min and maintained the stability at least four cycles. The degradation rate constant of Co₂SnO₄-SnO₂ was 0.149 min^-1, which was about 1.93, 2.98, 11.5 times higher than of Co₂SnO₄, Co₃O₄ and SnO₂, respectively. Notably, the leaching performance of Co₂SnO₄-SnO₂ was greatly suppressed to be 7.45 ug/L, which was lower than that of Co₂SnO₄ (6.41 mg/L) and Co₃O₄ (1.12 mg/L). Radical quenching and EPR experiments showed that singlet oxygen (¹O₂), rather than hydroxyl active species and sulfate radicals, played a predominating role for PMS activation in the Co₂SnO₄-SnO₂/PMS system. The intermediates and degradation routes for tetracycline degradation were characterized by liquid chromatograph-tandem mass spectrometry. This study expected to provide a novel strategy to construct heterostructural catalysts with lower cobalt ion leaching for the activation of PMS.

The potential of green biochar generated from biogas residue as a heterogeneous persulfate activator and its non-radical degradation pathways: Adsorption and degradation of tetracycline

Advanced oxidation aided by sulfate radicals (SO₄^-) is an effective option for the treatment of refractory pollutants from aqueous solutions. In this work, a metal-free biochar catalyst was prepared using pyrolyzed biogas residue as the raw material. The biogas residue carbon (BRC) obtained at 800 °C showed excellent catalytic activity and adsorption capacity for the removal of tetracycline (TC) with 97.9% of removal efficiency. Such performance is accounted for by the rich pores and accelerated electron transformability conferred by its defect structure with the crucial role of pyrolysis temperature in regulating catalyst properties. The BRC-800/peroxymonosulfate (PMS) system worked predominantly through non-radical pathways with high stability/recyclability without being interfered by organic/inorganic compounds in an actual water environment. The exceelent removal performance is also supported by the kinetic reaction rate of the BRC-800/PMS system as estimated to be 0.03017 min^-1. This work provides a simple and effective path for modifying biogas residue waste for versatile applications.

Insights on the electron transfer pathway of phenolic pollutant degradation by endogenous N-doped carbonaceous materials and peroxymonosulfate system

In this study, chitosan, a low-price and easily obtainable natural polymerized sugar containing abundant nitrogen element, was employed as a precursor for preparing hierarchically porous carbon (PC) to activate peroxymonosulfate (PMS). The PC fabricated at 800 °C obtained the optimum catalytic performance with complete removal of p-hydroxybenzoic acid (HBA) in 30 min. The selective degradation toward phenolic pollutants with different substituent groups and the resistance over the interference of typical anions and natural organic matter implied a non-radical pathway contributed most for HBA degradation. The investigation of structure-activity relationship suggested a positive linear correlation between graphitic N content and HBA removal. The chemical quenching experiment and electron paramagnetic resonance (EPR) excluded the crucial role of radicals and ¹O₂. Solid evidence based on electrochemical techniques demonstrated the essential contribution of electron transfer pathway achieved by three successive processes including the first close adsorption of PMS by PC800 to form metastable intermediates, then an internal electron transfer from active graphitic N to PMS within metastable intermediates and finally external electron transfer from HBA to metastable intermediates. This study provided insightful mechanism understanding of a promising organics elimination strategy by PMS activation through N-doped carbonaceous materials utilizing chitosan as a simultaneous carbon and nitrogen precursor.

N, S co-doped magnetic mesoporous carbon nanosheets for activating peroxymonosulfate to rapidly degrade tetracycline: Synergistic effect and mechanism

Heteroatoms doped carbon materials are widely used in the advanced oxidation process (AOPs) to remove organic pollutants in water due to the synergies effect between different heteroatoms. In this study, a novel kind of N, S co-doped magnetic mesoporous carbon nanosheets (Fe@NS-C) was prepared by simple one-step pyrolysis. Further, the influence of doping amount of S (L-methionine) and N (melamine) on catalytic activity was studied, the optimized sample Fe@NS-C-2-12/PMS showed a satisfying degradation ( 91.07%) for high concentrations of tetracycline (80 mg/L TC) in 10 min, which was attributed to the proper ratio of S content to N content (S(at.%)/ N(at.%)= 0.2097) in the sample could better play its synergistic effect by XPS analysis. The Fe@NS-C-2-12/ PMS system also exhibited satisfactory degradation effects in a wide pH range (3-10) and the existence of inorganic ions and humic acid. Then, the degradation mechanisms were mainly through the non-radical pathway (¹O₂ and electron transfer) and the major active sites were pyridinic N compared to thiophene S, CO, and Fe-N_x. This study could inspire the design of high-performance active and low-cost heteroatomic doping nano-magnetic catalysts for PMS-based waste treatment.

Preparation, characterization, and applications of Fe-based catalysts in advanced oxidation processes for organics removal: A review

Fe-based catalysts as low-cost, high-efficiency, and non-toxic materials display superior catalytic performances in activating hydrogen peroxide, persulfate (PS), peracetic acid (PAA), percarbonate (PC), and ozone to degrade organic contaminants in aqueous solutions. They mainly include ferrous salts, zero-valent iron, iron-metal composites, iron sulfides, iron oxyhydroxides, iron oxides, and supported iron-based catalysts, which have been widely applied in advanced oxidation processes (AOPs). However, there is lack of a comprehensive review systematically reporting their synthesis, characterization, and applications. It is imperative to evaluate the catalytic performances of various Fe-based catalysts in diverse AOPs systems and reveal the activation mechanisms of different oxidants by Fe-based catalysts. This work detailedly summarizes the synthesis methods and characterization technologies of Fe-based catalysts. This paper critically evaluates the catalytic performances of Fe-based catalysts in diverse AOPs systems. The effects of solution pH, reaction temperature, coexisting ions, oxidant concentration, catalyst dosage, and external energy on the degradation of organic contaminants in the Fe-based catalyst/oxidant systems and the stability of Fe-based catalysts are also discussed. The activation mechanisms of various oxidants and the degradation pathways of organic contaminants in the Fe-based catalyst/oxidant systems are revealed by a series of novel detection methods and characterization technologies. Future research prospects on the potential preparation means of Fe-based catalysts, practical applications, assistive technologies, and impact in AOPs are proposed.

Functionalized Magnetic Nanomaterials in Agricultural Applications

The development of functional nanomaterials exhibiting cost-effectiveness, biocompatibility and biodegradability in the form of nanoadditives, nanofertilizers, nanosensors, nanopesticides and herbicides, etc., has attracted considerable attention in the field of agriculture. Such nanomaterials have demonstrated the ability to increase crop production, enable the efficient and targeted delivery of agrochemicals and nutrients, enhance plant resistance to various stress factors and act as nanosensors for the detection of various pollutants, plant diseases and insufficient plant nutrition. Among others, functional magnetic nanomaterials based on iron, iron oxide, cobalt, cobalt and nickel ferrite nanoparticles, etc., are currently being investigated in agricultural applications due to their unique and tunable magnetic properties, the existing versatility with regard to their (bio)functionalization, and in some cases, their inherent ability to increase crop yield. This review article provides an up-to-date appraisal of functionalized magnetic nanomaterials being explored in the agricultural sector.

Active sites decoration on sewage sludge-red mud complex biochar for persulfate activation to degrade sulfanilamide

Active sites on catalyst surface play significant roles in oxidative species formation. The work focused on the regulation of main active sites on catalyst surface and oxidative species formation. Herein, sewage sludge (SS)-red mud (RM) complex biochar (SRCB) and N-functionalized SRCB (NSRCB) were served as activators of peroxymonosulfate (PMS) for sulfanilamide (SMX) degradation. Specially, NSRCB-1 showed excellent catalytic performance with 97.5% removal of SMX within 110 min. Additionally, the effects of N incorporation on the reconstruction of N species, conversion of intrinsic Fe species and ketonic CO groups in SRCB were studied systematically. Both radical (hydroxyl radicals (OH), sulfate radicals (SO₄^-) and superoxide radical (O₂^-)) and non-radical (electron transfer and singlet oxygen (¹O₂)) pathways were confirmed by quenching experiments, electron paramagnetic resonance (EPR) testing and electrochemical measurements. Ketonic CO groups, pyridinic N and pyrrolic N were responsible for non-radical pathway in SMX degradation process. Besides, Fe(II) modulated by N-doping was the main actives site for radicals generation. The contribution of active sites on catalyst surface to oxidative species formation provided fundamental basis for practical water treatment in PMS process.

Application of Magnetic Composites in Removal of Tetracycline through Adsorption and Advanced Oxidation Processes (AOPs): A Review

Water pollution induced by the tetracycline (TC) has caused global increasing attention owing to its extensive use, environmental persistence, and potential harm for human health. Adsorption and advanced oxidation processes (AOPs) have been promising techniques for TC removal due to ideal effectiveness and efficiency. Magnetic composites (MCs) which exploit the combined advantages of nano scale, alternative sources, easy preparation, and separation from wastewater are widely used for catalysis and adsorption. Herein, we intensively reviewed the available literature in order to provide comprehensive insight into the applications and mechanisms of MCs for removal of TC by adsorption and AOPs. The synthesis methods of MCs, the TC adsorption, and removal mechanisms are fully discussed. MCs serve as efficient adsorbents and photocatalysts with superior performance of photocatalytic performance in TC degradation. In addition, the TC can be effectively decomposed by the Fenton-based and SO4•− mediated oxidation under catalysis of the reported MCs with excellent catalytic performance. Based on the existing literature, we further discuss the challenge and future perspectives in MCs-based adsorption and AOPs in removing TC.

Fabrication of porous carbon derived from cotton/polyester waste mixed with oyster shells: Pore-forming process and application for tetracycline removal

Porous carbon was fabricated from cotton/polyester-based textile wastes as a carbon source coupled with oyster shells for tetracycline removal. The preparation conditions were optimized and detailed characterization was conducted to study the effects of oyster shells on cotton/polyester pyrolysis. The optimal pyrolysis temperature (900 °C), pyrolysis time (1 h) and mass ratio (OS/CPW of 1:1) were determined using the Box-Behnken experiment. The best porous carbon reached a surface area of 645.05 m²/g. Oyster shells acted as templates to produce cotton/polyester-based porous carbon and a possible pore-forming process was proposed. CaO was converted from CaCO₃, which played the dominant role in developing the mesoporous structure. CO₂ gas released from CaCO₃ promoted the creation of micropore structure. In addition, the impurites of oyster shells acted as the dispersing agent inhibiting CaCO₃ and CaO aggregation and growth. Fe₂O₃ and K₂O from impurities reacted with the carbon skeleton to increase microporosity. Finally, the well-developed and uniform porous carbon was obtained. The first-pseudo order model and Langmuir isotherms were suitable. The maximum adsorption capacity of PC-OS-900 was 515.17 mg/g which competed with other waste-based adsorbents. The TET adsorption mechanism was related to pore distribution, hydrogen bonds, π-π EDA interactions and electrostatic interactions.