FeS@BC prepared from natural pyrite and biomass as peroxydisulfate activator for sulfadiazine degradation.

The efficient degradation of SAs is a significant challenge for the treatment of wastewater. To address this, the FeS@BC was prepared by calcining a mixture of pyrite and biomass, and used to activate peroxydisulfate (PDS) to degrade sulfadiazine (SDZ). The effect of carbon sources (wheat straw, rice husk, and corn cob) on catalytic activity of FeS@BC were investigated by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), total Fe dissolution and free radical quantification.

Layer symmetry and irradiation dominate the oxidation capability of birnessite on biogenic isoprene.

The climate-active gas isoprene (CH) is one of the most abundant biogenic volatile organic compounds (VOCs). Soil is one of the significant sinks for isoprene, yet the role played by the naturally abundant birnessite in the soil surface layer during the oxidation of isoprene remains largely unknown. This study investigates the reactions of isoprene with triclinic and hexagonal birnessite on the Earth's surface environments.

Autocatalytic degradation of Cu-EDTA in the Calcite/PMS system: Singlet oxygen and Cu(III).

The simultaneous removal of heavy metal complexes (HMCs) and heavy metal ions presents a significant challenge in treating wastewater. To address this, we propose a Calcite/Peroxymonosulfate (Calcite/PMS) system aimed at simultaneously decomplexing Cu-EDTA and removing Cu ions. Calcite/PMS system could achieve 99.

Manganese sulfide-sulfur and limestone autotrophic denitrification system for deep and efficient nitrate removal: Feasibility, performance and mechanism.

Despite the great potential of sulfur-based autotrophic denitrification, an improvement in nitrate removal rate is still needed. This study used the desulfurized products of Mn ore to develop the MnS-S-limestone autotrophic denitrification system (MSLAD). The feasibility of MSLAD for denitrification was explored and the possible mechanism was proposed.

The pH-sensitive transformation of birnessite and its effect on the fate of norfloxacin.

Birnessite plays a crucial role in regulating the fate of contaminants in soil, which is affected by the crystal structure of birnessite. In this study, the transformation of triclinic birnessite to hexagonal birnessite was examined at various pH values, and their reactivity towards norfloxacin was investigated. The findings indicate that the conversion from triclinic birnessite to hexagonal birnessite occurs under pH conditions lower than 7.

The synergistic activation of peroxymonosulfate for the degradation of Acid Scarlet GR by palygorskite/MnO/FeO nanocomposites.

A heterogeneous Fenton-like system comprising palygorskite/MnO/FeO (PMM) as a superior, low-cost, and eco-friendly ternary catalyst for the activation of peroxymonosulfate (PMS) was investigated with regard to its ability to degrade Acid Scarlet GR in an aqueous solution. Under the optimum catalytic oxidation conditions of 1 g L PMM, 0.7 g L PMS, and an initial pH value of 5, 200 mg L Acid Scarlet GR was completely degraded within 300 min.

Phosphate adsorption kinetics and equilibria on natural iron and manganese oxide composites.

Although it is well known that phosphate retention in soils and sediments is strongly influenced by binding to secondary iron oxides, there have been relatively few studies examining its adsorption/desorption behavior on multicomponent particles of realistic natural complexity. In this study, natural Mn-rich limonite (LM), was used to prepare naturally complex Fe- and Mn-oxide composite materials to examine phosphate adsorption/desorption. To clarify the role of the Mn-oxides, results for the LM sample were compared to those for an acid treated version (LAT), in which the acid-extractable Mn-oxide fraction has been selectively eliminated while leaving the Fe-oxide fraction intact.

Ultrathin MnO-Coated FeOOH Catalyst for Indoor Formaldehyde Oxidation at Ambient Temperature: New Insight into Surface Reactive Oxygen Species and In-Field Testing in an Air Cleaner.

Herein, we tailored a series of ultrathin MnO nanolayers coated on the surface of commercial goethite (α-FeOOH) by a facile in situ chemical precipitation method. α-FeOOH inhibited the MnO crystal growth via the incorporation of K ions between MnO and α-FeOOH interfaces during the synthesis process. The hybrid design of MnO with an ultrathin nanolayer structure could reduce the electron transfer resistance and bring abundant oxygen vacancies, accelerating the activation of molecular O to generate more oxygen-free radical species and favoring the thermodynamic HCHO oxidation.

Ce(SO)/α-FeO selective catalytic reduction of NO with NH: preparation, characterization, and performance.

To achieve a low-cost, high-activity denitrification catalyst with excellent water and sulfur resistance, goethite and Ce(SO)·4HO were used to prepare Ce(SO)/α-FeO composite catalyst by the impregnation way and investigated the effect of Ce(SO) on the properties of goethite. Ce(SO)/α-FeO with various preparation conditions for denitration was systematically discussed, and its structure and properties were characterized by XRD, BET, TEM, XPS, H-TPR, and NH-TPD methods. The results showed that Ce(SO)/α-FeO over the Ce/Fe molar ratio of 0.

Utilization of methylene blue-adsorbed halloysite after carbonization to activate peroxymonosulfate degrading phenol: Performance and mechanism.

In this study, a new low-cost carbon-based material was prepared via the carbonization of methylene blue adsorbed halloysite (CMH) at different temperatures in a nitrogen atmosphere, which was named CMH-T (T-Temperature). The performance of CMH-T was explored and the effects of initial pH values, catalyst dosage, phenol (PE) concentrations, peroxymonosulfate (PMS) concentrations, and water background compounds on PE degradation were investigated systematically. The results indicated that CMH800 exhibited the best performance to activate PMS for degrading PE.

The synergistic effect of calcite and Cu on the degradation of sulfadiazine via PDS activation: A role of Cu(Ⅲ).

A system of Cu/calcite/PDS was constructed to degrade sulfadiazine (SDZ). Different from the traditional Cu-mediated activation, a low concentration of Cu that met drinking water standards (≤ 1 mg/L) transformed into Cu(Ⅱ) solid in the presence of calcite, and then enhanced the degradation of SDZ via PDS activation over a pH range from 3 to 9. According to scavenger and chemical probe experiments, Cu(Ⅲ), rather than radicals (hydroxyl radicals and sulfate radicals) and singlet oxygen, was the predominant reactive species, which was responsible for the degradation of SDZ.

HO activation over Co substitution in FeS for tetracycline degradation: Effect of Co substitution.

In this work, the effect of Co substitution in the FeS (CSP) on the activation of HO to degrade tetracycline (TC) is investigated. A series of CSP samples with different Co content are synthesized via a high-temperature sulfidation method and characterized by XRD, XPS, SEM, and electrochemical analysis. The result showed that low Co content (≤1%) promotes the catalytic activity of FeS, while excessive Co (1%﹤x ≤ 3%) inhibits its catalytic activity.

The removal performance and mechanisms of tetracycline over Mn-rich limonite.

Naturally occurring Mn-rich limonite mainly composed of goethite and manganese oxides was used to remove tetracycline (TC) from the aqueous solution. The effects of dosage, initial solution pH, temperature, and coexisting anions on TC removal were investigated. Results showed that 95% of TC (30.

Biodegradable microplastics (BMPs): a new cause for concern?

With the increasingly serious pollution of plastics, biodegradable plastics (BDPs) have attracted attention as a new material that can replace conventional plastics in certain applications. The global production of BDPs also gradually increases in recent years. However, unfortunately, with the application of BDPs, some potential problems are gradually exposed.

Degradation of norfloxacin by calcite activating peroxymonosulfate: Performance and mechanism.

In this study, calcite was investigated as an activator for the norfloxacin (NOR) degradation by peroxymonosulfate (PMS). Under optimum conditions, the NOR removal percentage was 99.7% within 60 min, and the pseudo-first-order kinetics effectively described the two-stage oxidation process.

The pH-dependent degradation of sulfadiazine using natural siderite activating PDS: The role of singlet oxygen.

Occurring naturally siderite (FeCO) was used as the heterogeneous catalyst to activate peroxodisulfate (PDS) for the degradation of sulfadiazine under different initial pH values. The findings of this system exhibited various ROS (e.g.

Decomposition of gaseous chlorobenzene using a DBD combined CuO/-FeO catalysis system.

Copper oxide and hematite (CuO/-FeO) composite catalysts were prepared by using goethite as precursor adopted impregnation way and applied to the dielectric barrier discharge (DBD) catalytic decomposition of gaseous chlorobenzene. The CuO/-FeO composite was characterised by X-ray diffraction, Brunauer-Emmett-Teller method, scanning electron microscopy and X-ray photoelectron spectrometer technique. The decomposition efficiency and energy yield of gaseous chlorobenzene in DBD catalysis system were studied by a function of gas flow rate, initial concentration and input voltage.

Effect of iron minerals during coaling on the transformation of NO in the presence of NH: Take pyrite as an example.

Pyrite, a naturally occurring mineral, can be found extensively in coal. The change in the pyrite structure that occurs during coaling process, the ability of the pyrite-derived α-FeO to convert NO in the presence of NH before catalyst bed and the kinetic study were investigated in this work. The pyrite-derived α-FeO was obtained by calcining at 500, 600, 700, 800 °C and was characterized by the X-ray diffraction (XRD), N physisorption, the X-ray photoelectron spectrometer (XPS), the scanning electron microscope (SEM), UV-visible near-infrared spectroscopy (UV-vis DRS), the temperature-programmed desorption of ammonia (NH-TPD) and the in situ diffuse reflectance infrared Fourier transform spectroscopy (in-situ DRIFTS).

The positive effect of siderite-derived α-FeO during coaling on the NO behavior in the presence of NH.

Siderite is a naturally occurring mineral that can be found extensively in coal. The structural evolution of siderite in the process of coaling and its performance in the transformation of NO in the presence of NH were investigated in this work. In addition, the effects of the coexisting component, including vapor, SO, and the alkali metal K, were also discussed.

A novel discovery of a heterogeneous Fenton-like system based on natural siderite: A wide range of pH values from 3 to 9.

Natural iron-bearing minerals have been proven to be effective for activating HO to produce OH, which can be used to degrade organic pollutants. In this study, the performance of siderite to degrade sodium sulfadiazine via catalytic HO degradation was investigated at different solution pH values from 3 to 9. An interesting discovery was made: the performance of the siderite-HO system was excellent under acidic, neutral, and even alkaline conditions.

[Preparation of Magnetic Biomass Carbon by Thermal Decomposition of Siderite Driven by Wheat Straw and Its Adsorption on Cadmium].

C-FeO composite material [magnetic biomass char (MBC)] was prepared by pyrolysis of a mixture of wheat straw and siderite at 500℃. The MBC was characterized by XRF, FTIR, XRD, SEM, XPS, and a magnetic susceptibility device. The effect of contact time, pH value, initial Cd concentration, and ionic strength on the adsorption capacity of the MBC to Cd was investigated.

The Adsorption of Cd(II) on Manganese Oxide Investigated by Batch and Modeling Techniques.

Manganese (Mn) oxide is a ubiquitous metal oxide in sub-environments. The adsorption of Cd(II) on Mn oxide as function of adsorption time, pH, ionic strength, temperature, and initial Cd(II) concentration was investigated by batch techniques. The adsorption kinetics showed that the adsorption of Cd(II) on Mn oxide can be satisfactorily simulated by pseudo-second-order kinetic model with high correlation coefficients (R² > 0.

Performance of selective catalytic reduction of NO with NH over natural manganese ore catalysts at low temperature.

Natural manganese ore catalysts for selective catalytic reduction (SCR) of NO with NH at low temperature in the presence and absence of SO and HO were systematically investigated. The physical and chemical properties of catalysts were characterized by X-ray diffraction, Brunauer-Emmett-Teller (BET) specific surface area, NH temperature-programmed desorption (NH-TPD) and NO-TPD methods. The results showed that natural manganese ore from Qingyang of Anhui Province had a good low-temperature activity and N selectivity, and it could be a novel catalyst in terms of stability, good efficiency, good reusability and lower cost.

[Preparation of -FeO Catalyst by Heat Treatment of Natural Limonite for Selective Catalytic Reduction of NO by NH].

Natural limonite was used as a precursor to prepare -FeO via thermal treatment. The influences of reaction temperature, manganese oxides existing in limonite and coexisting SO and HO on the catalytic reduction activity of the prepared-FeO were evaluated, and the activity of SCR was compared with that of -FeO, by means of XRD, XRF, XPS, NH-TPD, FT-IR and so on. The results showed that because the surface acidity of -FeO is stronger, the SCR temperature window of -FeO was 200-350℃ being broader than that of -FeO (200-300℃), and in the active temperature window, the NO removal reached over 99%.

[Photocatalytic Degradation of Gaseous Toluene by a Photo-Fenton Reaction].

In this study, the performance of photo-Fenton reaction on decomposition of toluene was investigated by a flowing column using toluene as a representative of volatile organic pollutants (VOCs). The effects of initial pH, H2O2 concentration, Fe2+ concentration, initial concentration of toluene on degradation of toluene by photo-Fenton reaction were evaluated. Mass spectrometry and gas chromatograph were utilized to detect the products.