Oxidative Degradation Method Research Articles

Mathematical simulation of damage detection for fighting athletes and equipment based on conjugated polymer development.

Traditional combat sports equipment usually uses synthetic materials, such as polyurethane and synthetic leather. Although these materials have a certain degree of strength and durability, they have poor flexibility and antibacterial properties, making it difficult to provide stable support and protection for athletes. In order to enhance the antibacterial properties and flexibility of sports equipment and reduce the risk of injuries to athletes, this article conducts in-depth research on the development of combat sports equipment using conjugated polymers. This article first selects polypropylene (PP) as the base material for sports equipment for combat athletes, and uses the gas phase polymerization method to prepare the material; then uses chitosan as an antimicrobial agent and uses the oxidative degradation method to prepare it; after that, this article coats the chitosan antibacterial agent on the prepared PP material, and uses a combination of dipping and calendering for antibacterial treatment; finally, this article uses the spunbond melt-blown composite method to fill and combine the top equipment of combat athletes to achieve the structural design of sports equipment. In order to verify the effectiveness of the equipment, this article conducted equipment performance testing and sports injury simulation. The results showed that the average diameter of the antibacterial zone of this sports equipment reached more than 1 mm, and in the injury risk test, the risk of athletes' joint and muscle injuries was reduced by 16.9% and 20.5% respectively. Research shows that developing combat sports equipment based on conjugated polymers can help reduce the risk of injury to athletes and improve the safety of combat sports.

Synthesis and Properties of the Novel High-Performance Hydroxyl-Terminated Liquid Fluoroelastomer.

Functional liquid fluoroelastomers are in high demand in new energy fields. And these materials have potential applications in high-performance sealing materials and as electrode materials. In this study, a novel high-performance hydroxyl-terminated liquid fluoroelastomer (t-HTLF) with a high fluorine content, temperature resistance, and curing efficiency was synthesised from a terpolymer of vinylidene fluoride (VDF), tetrafluoroethylene (TFE), and hexafluoropylene (HFP). A carboxyl-terminated liquid fluoroelastomer (t-CTLF) with controllable molar mass and end-group content was first prepared from a poly(VDF-ter-TFE-ter-HFP) terpolymer using a unique oxidative degradation method. Subsequently, an efficient "one-step" reduction of the carboxyl groups (COOH) in t-CTLF into hydroxyl groups (OH) was achieved via the functional-group conversion method using lithium aluminium hydride (LiAlH4) as the reductant. Thus, t-HTLF with a controllable molar mass and end-group content and highly active end groups was synthesised. Owing to the efficient curing reaction between OH and isocyanate groups (NCO), the cured t-HTLF exhibits good surface properties, thermal properties, and chemical stability. The thermal decomposition temperature (Td) of the cured t-HTLF reaches 334 °C, and it exhibits hydrophobicity. The oxidative degradation, reduction, and curing reaction mechanisms were also determined. The effects of solvent dosage, reaction temperature, reaction time, and ratio of the reductant to the COOH content on the carboxyl conversion were also systematically investigated. An efficient reduction system comprising LiAlH4 can not only achieve an efficient conversion of the COOH groups in t-CTLF to OH groups but also the in situ hydrogenation and addition reactions of residual double bonds (C=C) groups in the chain, such that the thermal stability and terminal activity of the product are improved while maintaining a high fluorine content.

Azobisisobutyronitrile loaded on mesoporous silica particles: A new stressor for solid-state oxidative forced degradation studies

A new approach for testing drug sensitivity to autooxidative degradation in the solid state is demonstrated in this work. A novel solid-state form of stressing agent for autooxidation has been proposed, based on azobisisobutyronitrile loaded into mesoporous silica carrier particles. The new solid-state form of the stressing agent was applied in degradation studies of two active pharmaceutical ingredients: bisoprolol and abiraterone acetate. The effectiveness and predictivity of the method were evaluated by comparing impurity profiles with those obtained by traditional stability testing of commercial tablets containing the investigated APIs. The results obtained by the new solid-state stressor were also compared with those obtained by an existing method for testing peroxide oxidative degradation in the solid state using a complex of polyvinylpyrrolidone with hydrogen peroxide. It was found that the new silica particle-based stressor was able to effectively predict which impurities could be formed by autooxidation in tablets and that this new approach is complementary to methods for testing peroxide oxidative degradation known from the literature.

Recycling of ammonia-cured epoxy resin by oxidative degradation of nitric acid assisted by swelling agent

Because of its high crosslinking density, compact structure and stable performance, epoxy resin is difficult to be degraded, which leads to serious environmental pollution problems. In this work, using dipropylene glycol dimethyl ether as swelling agent and nitric acid as oxidant, the degradation of amine cured epoxy resin was studied. Results are as follows: The degradation rate obtained by swelling agent assisted oxidation degradation method is much higher than that obtained by oxidation degradation method only. And the degradation rate of the epoxy resin even reached 100 % at 100 °C only in an hour under the condition of swelling agent assisted nitric acid. FT-IR and GC–MS showed that the degradation was mainly caused by that the CN bond in the molecular chain was gradually weakened and fractured finally. The molecular weight of the degradation product was relatively dispersive, which was composed of low molecular polymer and small fragments, and the molecular weight of low molecular polymer was about 2167. And the degradation products primarily contain 4-isopropylphenol and (allyloxy)benzene rings. This work provides a new way to solve the problem about the degradation, recycling and pollution of epoxy resin.

Oxidative destruction of chlorinated persistent organic pollutants by hydroxyl radicals via ozone and UV light irradiation

We demonstrate a simple, and economically feasible method for oxidative degradation of organochlorinated compounds and persistent organic pollutants at room temperature using inexpensive and eco-friendly ozone gas under ultraviolet irradiation.

Structure, preparation and properties of liquid fluoroelastomers with different end groups.

In order to design and prepare liquid fluoroelastomers with different end groups, and reveal the relationship between the molecular chain structure and properties, we studied on the oxidation degradation method and functional group conversion method to prepare carboxyl-terminated and hydroxyl-terminated liquid fluoroelastomers, respectively. The reaction mechanisms were also deduced. Furthermore, the curing system was created for liquid fluoroelastomers, and systematically analyzed their properties. The sequence type and content of the –C Created by potrace 1.16, written by Peter Selinger 2001-2019 ]]> C– and oxygen-containing groups in the samples were measured and characterized by attenuated total reflectance/Fourier transform infrared (ATR-FTIR) spectroscopy, 1H nuclear magnetic resonance (1H-NMR), 19F-NMR spectroscopy and chemical titration, the molecular weights of liquid fluoroelastomers were measured by gel permeation chromatography (GPC). Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to examine the thermal properties, while a viscometer was used to measure the dynamic viscosity of the liquid fluoroelastomers. Then the mechanical and surface properties of the cured samples were examined by universal testing machine and contact angle measurement instrument, respectively. The results show that carboxyl-terminated liquid fluoroelastomer with 2.71 wt% carboxyl terminal groups can be prepared by oxidation degradation method. When lithium aluminium hydride (LiAlH4) was used as the reducing agent, it can efficiently convert carboxyl group to hydroxyl group with a conversion rate of more than 95%. In addition, it can be seen that the dynamic viscosity of the liquid fluoroelastomers were all decreased with the increase of temperature, and it is similar to about 10 Pa s at 70 °C. Compared with carboxyl-terminated liquid fluoroelastomers, hydroxyl-terminated liquid fluoroelastomers has higher curing reactivity, higher glass transition temperature (Tg) and thermal decomposition temperature (Td), and better mechanical properties of cured samples. The two types of liquid fluoroelastomers with distinct end groups presented distinct hydrophilicity.

МІКРО- І НАНОСТРУКТУРОВАНИЙ ТИТАНУ(IV) ОКСИД У СОНО-, ФОТО- І СОНОФОТОКАТАЛІТИЧНІЙ ДЕГРАДАЦІЇ КСАНТЕНОВОГО БАРВНИКА РОДАМІНУ Б (ОГЛЯД)

Adsorption methods for removing Rhodamine B from wastewater and oxidative degradation methods based on the use of advanced oxidation processes (sonolysis, photolysis, sono-, photo- and sonophotocatalysis) are considered. It was established that naturally occurring materials (such as clays, zeolites, coal ash, anaerobic sludge, agricultural solid wastes) and their modified or activated analogues are used as adsorbents for the removal of Rhodamine B. The possible mechanism of photo- and sonophotocatalytic degradation of Rhodamine B in the presence of micro- and nanostructured titanium (IV) oxide is presented. The effectiveness of its application for degradation of Rhodamine B is analyzed.

Effect of sulfated modification on rheological and physiological properties of oat β-glucan oligosaccharides prepared by acid or oxidative degradation

Two kinds of oat β-glucan oligosaccharides (βG-H and βG-O) were obtained by acid and oxidative degradation methods, respectively. Further, six kinds of sulfated oat β-glucan oligosaccharides (βG-H-S1, βG-H-S2, βG-H-S3, βG-O-S1, βG-O-S2, and βG-O-S3) with different degree of substitution were prepared by controlling the reaction time. The structure analysis showed that the molecular weights (Mw) and degree of substitution (DS) of sulfated oat β-glucan oligosaccharides increased with the prolonged reaction time. After sulfated modification, the apparent viscosity of oat β-glucan oligosaccharides increased and their viscoelasticity was changed. Sulfated modification endowed βG-H with enhanced fat binding capacity and bile acid binding capacity, and the above-mentioned properties increased with the increasing Mw and DS. Meanwhile, sulfated modification endowed βG-O with enhanced fat binding capacity and attenuated bile acid binding capacity, and the capacities of βG-O-S decreased with the increasing Mw and DS. Sulfated modification enhanced hypoglycemic effect of oat β-glucan oligosaccharides, it showed ability to decrease the glucose availability and inhibit α-glucosidase activity. The results revealed that the physiological properties of sulfated β-glucan oligosaccharides depend on their Mw, DS, and degradation method of β-glucan oligosaccharides.

Effect of acid and oxidative degradation on the structural, rheological, and physiological properties of oat β-glucan

Two types of oat β-glucan oligosaccharides (βG-H and βG-O) with similar molecular weights were prepared by using acid and oxidative degradation methods, respectively. Their structures were characterized and the physiological functionality were evaluated. Fourier transform infrared spectroscopy (FT-IR) results showed that both βG-H and βG-O possessed the characteristic absorption peak of oat β-glucan. Besides, a new absorption band at 1723 cm−1 in βG-O implied the formation of carboxylic groups caused by oxidative degradation of oat β-glucan. The carbonyl and carboxyl contents increased sharply in βG-O. Viscosity decreased and viscoelastic property varied after degradation of oat β-glucan. During degradation, the properties related to the viscosity of oat β-glucan changed and the swelling power of βG-H and βG-O disappeared. Fat binding capacity and bile acid binding capacity of oat β-glucan increased after acid or oxidative degradation; βG-H exhibited stronger fat binding capacity and βG-O possessed better bile acid binding capacity. In a chemical digestion experiment, the glucose availability of digestive system treated with oat β-glucan, βG-O, and βG-H was 29.92, 36.56, and 20.67 mmol/L, respectively. The results indicated that acid degradation could endow oat β-glucan with enhanced hypoglycemic effect. The antioxidant and antibacterial activities of oat β-glucan increased after acid or oxidative degradation. The DPPH free radical scavenging activity, chelating ability on ferrous iron, and inhibition activity of lipid peroxidation of βG-H is better than that of βG-O, but the βG-O exhibited stronger reducing power. Antibacterial activity of βG-H and βG-O against Staphylococcus aureus is stronger than that against Escherichia coli, and βG-H possessed stronger antibacterial activities than βG-O. The results revealed that degradation methods have a great impact on the structure of oat β-glucan, and further influenced the functionalities and bioactivities of oat β-glucan.

Degradation of different molecular weight fucoidans and their inhibition of TGF-β1 induced epithelial–mesenchymal transition in mouse renal tubular epithelial cells

In order to investigate the anti-fibrotic effect of different molecular weight (Mw) fucoidans on TGF-β1-induced mouse renal tubular epithelial cell (MTEC) mode. Oxidative degradation method was used to obtain fucoidans with different molecular weights and the reaction time, reaction temperature and the concentration of oxidants were investigated. Cell viability was detected by CCK-8, and EMT markers expression was detected by Western-bolt and Cell immunofluorescence assay. As a result, after chemical analysis of three independent batches of prepared samples, one batch of fucoidan sample (LHX 1–9) which chemical contents are similar but Mw ranging from 3.3 KDa to 49.3 KDa were selected to do further research. We found LHX1 (Mw = 3.3 KDa) and LHX 3–9 (Mw = 6.6 KDa, 8.3 KDa, 11.3 KDa, 14.9 KDa, 25.2 KDa, 35.4 KDa, 49.3 KDa) could resist the TGF-β1-induced depithelial–mesenchymal transition (EMT) by decreased expression of Fn and CTGF and maintained epithelial cell morphology in MTEC. However, the relationship between the Mw of fucoidans and their anti-EMT effect is not simply linear. Among the samples, LHX 1, 5 and 8 showed significant anti-EMT effects than others by de-regulated Fn and CTGF expression on MTEC cells.

The Characterization of Hydroxyl Terminated Epoxidized Natural Rubber (HTENR) via Oxidation Degradation Method

The degradation of epoxidized natural rubber (ENR-50) and liquid epoxidized natural rubber (LENR) was done via oxidative degradation method for the production of hydroxyl terminated epoxidized natural rubber (HTENR) and hydroxyl terminated liquid epoxidized natural rubber (HTLENR) has been analysed. Cobalt (II) acetylacetonate (CAA) were used as an oxidizing agent for chain scission reaction at temperature 60 °C in the presence of ethanol. The reaction temperature was fixed at 60 °C meanwhile reaction time and the amount of CAA were varied according to the reaction formulation. The HTENR and HTLENR obtained have been characterized using Gel Permeation Chromatography (GPC), Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR). GPC were used to determine the molecular weight before and after the oxidative degradation of respected HTENR and HTLENR were compared with ENR-50 and LENR. The lowest Mn and Mw of HTLENR that were obtained from the oxidative degradation method were found to be 5,163 g/mol and 58,087 g/mol. The appearances of OH end groups were verified by FTIR and NMR analyses to validate the position of each OH functional groups. FTIR analysis confirmed that HTENR and HTLENR contained OH group with the appearance of a broad peak around 3,400 cm-1 to 3,550 cm-1 after the reaction. The presence of OH end groups was verified by NMR analysis with the appearance at 3.39 ppm and 3.66 ppm, corresponding to methylene proton adjacent to hydroxyl group in HOCH2CH2CH2 and methane proton adjacent to OH group in CH2CH2CH(OH)CH3.

Preparation of Reinforced Hydroxyl Terminated Liquid Epoxidized Natural Rubber Nanocomposite by Grafting of Graphene Oxide

Abstract In this research, liquid epoxidized natural rubber (LENR) with active end group which known as hydroxyl terminated liquid epoxidized natural rubber (HTLENR) has been synthesized via oxidative degradation method in the presence of cobalt acetyl-acetonate (CAA) and sodium borohydride (NaBH4). The conversion of LENR to HTLENR is vital to fully utilise the great properties of this liquid rubber and enable for further chemical modification. The molecular weight of the prepared HTLENR were confirmed using gel permeation chromatography (GPC) and weight average molecular weight (MW) of HTLENR revealed a slight decrease in comparison to MW of LENR at one hour reaction. Whilst the structure of LENR and HTLENR were studied using Fourier transform infra-red (FTIR) and neutron magnetic resonance (NMR). Subsequently graphene oxide (GO) has been inserted onto HTLENR backbone via grafting method. The efficiency of grafting was confirmed using Fourier transform infra-red (FTIR) analysis. HTLENR/GO nanocomposite prepared is important to be serve as a potential toughening agent which can be used in various applications such as aerospace, structural and automotive.

A novel method for oxidative degradation of metanil yellow azo dye by hexacyanoferrate(III) ions.

In the present work, the degradation of metanil yellow, an azo dye, by hexacyanoferrate(III) ions (oxidant) in the aqueous alkaline medium has been investigated by kinetic-spectrophotometric method at λmax 435nm of the reaction mixture. The effect of various parameters such as the concentration of dye, oxidant, and solution pH on the reaction rate has been determined. The results show that the rate of degradation increases linearly with the increase in concentrations of oxidant and dye at optimum pH of 9.0 and constant temperature of 40±0.1°C. Thermodynamic parameters such as energy of activation, enthalpy of activation, entropy of activation, and energy of formation have been calculated by studying the reaction rate at four different temperatures, that is, 40-55°C. Based on the experimental results, a plausible reaction mechanism involving complex formation has been proposed and a rate law has been derived. UV-Vis and LC-MS methods of analysis of degradation products show the formation of simpler and less hazardous degradation products. PRACTITIONER POINTS: It is also observed that the time required for azo dye degradation by the present method is about ten times less than the reported methods. Thus degradation of azo linkage and formation of simple and less hazardous products (efficient degradation of dye) makes it a novel method.

Antiviral Activity against Avian Leucosis Virus Subgroup J of Degraded Polysaccharides from Ulva pertusa.

Avian Leukosis Virus Subgroup J (ALV-J), a retrovirus of avian, has caused enormous economics losses to poultry industry around the world. Polysaccharides from marine algae are featured diversity bioactivities. To find the potential effect to prevent ALV-J spread, in this study, polysaccharides from Ulva pertusa (UPPs) and four low molecular weight (Mw) U. pertusa polysaccharides (LUPPs) were prepared and their functions on ALV-J were investigated. Firstly, LUPPs were obtained by hydrogen peroxide (H2O2) oxidative degradation. The effects of degradation conditions on Mw of the UPP were also investigated. Results showed that the H2O2 oxidative degradation method could degrade UPP effectively, and the degradation was positively related to H2O2 concentration and temperature and negatively to pH. The chemical characteristics of UPP and LUPPs were also determined. Afterwards, the anti-ALV-J activity of the polysaccharides were carried out in vitro. Results showed that UPP and LUPPs could inhibit ALV-J and LUPP-3 and Mw of 4.3 kDa exerted the strongest suppression. The action phase assay showed that LUPP-3 could bind with the viral particles and prevented ALV-J adsorption onto the host cells. And the ALV-J relative gene and gp85 protein expression were significantly suppressed after being administration with LUPP-3. Therefore, the low Mw polysaccharides from U. pertusa have great potential as an anti-ALV-J drug alternative.

Preparation of Telechelic Hydroxyl Low Molecular Weight Fluoropolymers

Preparation of telechelic hydroxyl low molecular weight fluoropolymers by reduction reaction was presented. The telechelic carboxyl low molecular weight fluoropolymers were chosen as raw materials which were prepared by oxidative degradation method. The molecular weights of telechelic carboxyl low molecular weight fluoropolymers were about 3700. Then, using lithium aluminum hydride reacted with carboxyl groups to prepare the telechelic hydroxyl low molecular weight fluoropolymers. The effects of reaction temperatures, reaction times, contents of solvent and lithium aluminum hydride were investigated in detail. The structures, Mn and dynamic viscosity of low molecular weight fluoropolymers were analyzed by FTIR, 1H-NMR, GPC and viscometer respectively. Finally telechelic hydroxyl low molecular weight fluoropolymers were prepared. The conversion rate of that reduction reaction was about 95%. The product was a viscous fluid with a dynamic viscosity of 48Pa·s at 50°C.

H2O2 oxidative preparation, characterization and antiradical activity of a novel oligosaccharide derived from flaxseed gum.

In this present study, a novel flaxseed gum oligosaccharide (FGOS) was prepared by H2O2 oxidative degradation method followed by physicochemical properties characterization and antiradical activity evaluation. Results indicated that the degradation rate of flaxseed gum is 37.81% under the optimum conditions (i.e., reaction temperature of 120°C, H2O2 concentration of 0.2M and reaction time of 2.0h) and FGOS as a reddish brown semisolid was obtained. Physicochemical properties identification showed that FGOS has a molecular weight of 1047Da and is a typical oligosaccharide which contains uronic acid. Characterizations showed FGOS is acid glycopyranose that consists of rhamnose, fucose, xylose, mannose, arabinose, glucose and galactose with mole percentages of 8.26%, 7.54%, 12.85%, 7.93%, 29.31%, 14.28% and 19.82% respectively. FGOS exhibited good free radical scavenging ability (OH 82.58%, DPPH 52.74% and ABTS 91.29% at most, respectively), suggesting its potent antiradical activity.

Preparation of Low Molecular Weight Chondroitin Sulfates, Screening of a High Anti-Complement Capacity of Low Molecular Weight Chondroitin Sulfate and Its Biological Activity Studies in Attenuating Osteoarthritis.

Chondroitin sulfate (CS) plays important roles in the complement system. However, the CS structure is complicated due to different sources and the number and positions of sulfate groups. The objective of this study was to prepare different low molecular weight chondroitin sulfates (LMWCSs) and to investigate the biological activity in anti-complement capacity. A series of LMWCSs was prepared from different sources and characterized by ultraviolet-visible (UV) spectroscopy, high-performance liquid chromatography (HPLC), size exclusion chromatography-multiangle laser light scattering (SEC-MALLS) and nuclear magnetic resonance (NMR) spectroscopy. Hemolytic, anti-complement 3 deposition capacity and cell viability assays were carried out to investigate the biological activities in vitro. The results showed that LMWCS prepared from shark cartilage with the oxidative degradation method (LMWCS-S-O) had the best anti-complement capacity. LMWCS-S-O could inhibit the alternative pathway of the complement system and protect chondrocytes from cell death. The attenuating effect of LMWCS-S-O on Osteoarthritis (OA) was investigated by destabilization of the medial meniscus (DMM) model in vivo. Functional wind-up, histological and C5b-9 analyses were used to evaluate the treatment effect on the OA model. In vivo results showed that LMWCS-S-O could attenuate OA. LMWCS-S-O with a high content of ΔDi-2,6diS and ΔDi-6S could be used for attenuating OA through regulating the complement system.

Electrochemical oxidation coupled with liquid chromatography and mass spectrometry to study the oxidative stability of active pharmaceutical ingredients in solution: A comparison of off-line and on-line approaches

Stability studies of pharmaceutical drug products and pharmaceutical active substances are important to research and development in order to fully understand and maintain product quality and safety throughout its shelf-life. Oxidative forced degradation studies are among the different types of stability studies performed by the pharmaceutical industry in order to understand the intrinsic stability of drug molecules. We have been comparing the use of electrochemistry as an alternative oxidative forced degradation method to traditional forced degradation and accelerated stability studies. Using the electrochemical degradation approach the substrate oxidation takes place in a commercially available electrochemical cell and the effluent of the cell can be either a) directly infused into the mass spectrometer or b) injected in a chromatographic column for separation of the different products formed prior to the mass spectrometry analysis. To enable the study of large numbers of different experimental conditions and molecules we developed a new dual pump automated electrochemical screening platform. This system used a HPLC pump and autosampler to load and wash the electrochemical cell and deliver the oxidized sample plug to a second injection loop. This system enabled the automatic sequential analyses of large numbers of different solutions under varied experimental conditions without need for operator intervention during the run sequence. Here we describe the system and evaluate its performance using a test molecule with well characterized stability and compare results to those obtained using an off-line electrochemistry approach.

Dramatically enhanced Fenton oxidation of carbamazepine with easily recyclable microscaled CuFeO 2 by hydroxylamine: Kinetic and mechanism study

Abstract In this study, an inorganic reductant hydroxylamine was used to enhance the Fenton degradation of carbamazepine by easily recyclable microscaled CuFeO2 in a wide pH range (pH 4.0–9.0). It was found that the addition of hydroxylamine could dramatically enhance the degradation rate and TOC removal of carbamazepine, better than other reductants such as benzoquinone and ascorbic acid. In the CuFeO2-H2O2 Fenton system, only 31% CBZ (50 μmol L−1) was removed at pH of 7.0 in 60 min in the presence of 1.0 g L−1 CuFeO2 and 20 mmol L−1 H2O2, while CBZ can be nearly completely removed in 60 min after the addition of 0.1 mmol L−1 hydroxylamine under the similar conditions. Moreover, CBZ degradation followed the pseudo first-order kinetics in the CuFeO2-H2O2 Fenton system, while in the hydroxylamine enhanced CuFeO2-H2O2 Fenton system, CBZ degradation followed the pseudo second-order kinetics. In the CuFeO2-H2O2 Fenton system, t1/2 value for CBZ degradation was calculated as 114.4 min and the value was greatly decreased to 1.8 min after the addition of hydroxylamine. This hydroxylamine induced dramatic carbamazepine degradation enhancement could be attributed to the hydroxylamine enhanced Fe(III)/Fe(II) and Cu(II)/Cu(I) redox cycles. Hydroxyl radicals were the primary radical species responsible for the carbamazepine degradation. As a microscaled catalyst, micro-CuFeO2 can be easily recovered by gravity settlement and exhibited good catalytic stability during six successive degradation cycles. Therefore, the couple of CuFeO2-H2O2-hydroxylamine is a promising method for oxidative degradation of organic pollutants in the actual aqueous environmental systems.

Degradation performance of crystal violet over CuO@AC and CeO2-CuO@AC catalysts using microwave catalytic oxidation degradation method

Herein, we reported a novel microwave catalytic oxidation degradation method for the degradation of crystal violet wastewater without adding any oxidants. The two catalysts of CuO@AC and CuO-CeO2@AC obtained from impregnation using activated carbon (AC) as the supports, and oxidants were hydroxyl radicals (OH) generated during the microwave catalytic reaction. The effects of parameters such as metal loadings, catalyst dosages, microwave power, reaction time, and initial concentration on degradation were studied. Results indicated that both CuO@AC and CuO-CeO2@AC can greatly enhance degradation rate compared with pure AC catalysts using microwave catalytic oxidation degradation method. Importantly, CuO-CeO2@AC showed higher catalytic performance than CuO@AC, and the former also had some advantages such as high degradation rate, short irradiation time and no secondary pollution. Therefore, CuO-CeO2@AC combined with the microwave catalytic oxidation degradation route is very promising for removal of crystal violet wastewater in wastewater treatment application.