| 1. |
- Ding, Pengjia, et al.
(författare)
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NiCo2O4 hollow microsphere–mediated ultrafast peroxymonosulfate activation for dye degradation
- 2021
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Ingår i: Chinese Chemical Letters. - : Elsevier. - 1001-8417 .- 1878-5964. ; 32:8, s. 2495-2498
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Tidskriftsartikel (refereegranskat)abstract
- Morphology and dispersity are key factors for activating peroxymonosulfate (PMS). In this study, we designed a recyclable open-type NiCo2O4 hollow microsphere via a simple hydrothermal method with the assistance of an NH3 vesicle. The physical structure and chemical properties were characterized using techniques such as scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), N2 adsorption and X-ray photoelectron spectroscopy (XPS). The test results confirm that the inner and outer surfaces of open-type NiCo2O4 hollow-sphere can be efficiently utilized because of the hole on the surface of the catalyst, which can minimize the diffusion resistance of the reactants and products. Under optimized conditions, the total organic carbon (TOC) removal efficiency of rhodamine B (RhB) can reach up to 80% in 40 min, which is almost 50% shorter than the reported values. The reactive radicals were identified and the proposed reaction mechanism was well described. Moreover, the disturbances of HCO3−, NO3−, Cl− and H2PO4− were further investigated. As a result, HCO3− and NO3− suppressed the reaction while Cl− and H2PO4− had a double effect on reaction.
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| 2. |
- He, Yingnan, et al.
(författare)
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Separable amino-functionalized biochar/alginate beads for efficient removal of Cr(VI) from original electroplating wastewater at room temperature
- 2022
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Ingår i: Journal of Cleaner Production. - : Elsevier. - 0959-6526 .- 1879-1786. ; 373
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Tidskriftsartikel (refereegranskat)abstract
- An alginate gel bead composite adsorbent with polyethyleneimine (PEI) as a surface modifier and Eichhornia crassipes (EC) biochar, known as EC-alg/PEI-3, was added internally to the adsorb Cr(VI) from an aqueous environment. The functionalized gel beads were characterized using SEM, XPS, FTIR, and other techniques. The maximum adsorption capacities of EC-alg/PEI-3 were 714.3 mg g−1 at 10 °C and 769.2 mg g−1 at 25 °C. In the treatment of highly concentrated electroplating wastewater, EC-alg/PEI-3 can be dosed at 1.4 g L−1 to reduce the concentration of Cr(VI) to below 0.05 ppm. EC-alg/PEI-3 maintained a competitive adsorption capacity after six cycles. This spherical adsorbent material is easy to prepare, has a very high adsorption capacity, is environmentally friendly, and can be easily recycled. The EC-alg/PEI-3 gel beads are promising for the treatment of industrial wastewater.
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| 3. |
- Jia, Xiuxiu, et al.
(författare)
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Mesopore-rich badam-shell biochar for efficient adsorption of Cr(VI) from aqueous solution
- 2021
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Ingår i: Journal of Environmental Chemical Engineering. - : Elsevier. - 2213-3437. ; 9:4
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Tidskriftsartikel (refereegranskat)abstract
- Cr(VI) is a common pollutant in wastewater and many previous studies using biochar-based materials as adsorbents for their well adsorption performance. However, the preparations of some biochars are complex, uneconomical, and with a poor reusability, which set limit on their practical application. Here, a mesoporous-rich biochar-based Cr(VI) adsorbent was easily prepared by pyrolyzing the badam-shell that in situ activated by concentrated phosphoric acid (H3PO4), with the aim of improving the removal effect of Cr(VI) in an aqueous solution. The partition coefficient (PC) was used to compare the performance of adsorbents more comprehensively, and the maximal PC value of the activated badam-shell biochar (ABSB) was 978.8 L g-1. In addition, its maximum adsorption capacity was 276.6 mg g-1. ABSB has a superior removal effect on the relatively low concentration of Cr(VI) (= 50 mg L-1), and residual Cr(VI) can meet the maximum emission standard (< 0.5 mg L-1) of industrial wastewater. The specific surface area of ABSB (1359.5 m2 g-1) was approximately four times that of pristine badam-shell biochar (BSB) (371.87 m2 g-1). The adsorption mechanisms involved were redox, complexation, electrostatic attraction and hydrogen bonding. The removal rate of Cr(VI) on ABSB remained at 81.6% after six cycles of adsorption-desorption. In a word, our study provides a simple, economic, and environmental method in fabricating the new adsorbent, which is highly promising and will not cause secondary pollution.
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| 4. |
- Li, Xue, et al.
(författare)
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Self-supported porous copper oxide nanosheet arrays for efficient and selective electrochemical conversion of nitrate ions to nitrogen gas
- 2023
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Ingår i: Journal of Materials Science & Technology. - : Elsevier. - 1005-0302. ; 137, s. 104-111
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Tidskriftsartikel (refereegranskat)abstract
- Electrochemical techniques have shown advantages for the removal of low-concentration nitrate. Here, copper oxide nanosheets were grown on self-supporting nickel foam (NF) to prepare electrodes (CuO/NF), which realized the rapid and highly selective conversion of nitrate pollutants in sewage into nontoxic and harmless N2. The CuO/NF afforded 100% NO3– removal within 100 min and 99.53% selectivity for N2 at –50 mA without producing a lot of by-products (NO2–, NH4+, and N2H4). Furthermore, 81.8% of NO3– was removed under the given conditions after six experimental repetitions. These results suggest that the catalyst has excellent electrochemical stability. The performance of CuO/NF for the electrocatalytic removal of NO3– in simulated wastewater (which contained Cl– and SO42–) was almost unaffected. Because of the high efficiency, high stability, and low cost of CuO/NF, this catalyst is practical for the removal of nitrate for wastewater purification.
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| 5. |
- Zeng, Yanbo, et al.
(författare)
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A simple polypropylene fiber membrane embedded with clean La(OH)3 nanoparticles for highly efficient phosphate anions removal
- 2022
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Ingår i: Journal of Environmental Chemical Engineering. - : Elsevier. - 2213-3437. ; 10:5
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Tidskriftsartikel (refereegranskat)abstract
- Lanthanide materials are attracting increasing attention owing to their ability to strongly bind with phosphorus (P). In this paper, a novel method of producing clean lanthanum nano-aerosols by spark ablation is proposed, the particles are uniformly deposited on a cheap and readily available Polypropylene(PP) fiber membrane in a special gas environment, and combined with water (solvent) for hydrothermal synthesis of the new material, PP-La. Material characterization confirmed that the formation of La(OH)3 nanoparticles and ligand exchange plays an important role in the phosphorus adsorption process, extended X-ray absorption spectroscopy demonstrated that phosphate was bound to the lanthanum site. The adsorption capacity of PP-La for phosphate is 188.6 mg P/g La, and the cost index (capacity/synthesis cost) is 132.54 mg P/USD. In addition, unlike most sorbents, PP-La has the advantage of being easily separated from water. This synthesis method is green and simple, the lanthanum is not toxic, the Polypropylene fiber membrane is cheap and has better mechanical strength, and the application prospect is very broad. Our results provide a new strategy for the development of efficient adsorbents and the treatment of eutrophication by selective adsorption of phosphate in lakes, reservoirs, rivers, and other water bodies.
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| 6. |
- Zhang, Yunqiu, et al.
(författare)
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Nanomanganese cobaltate-decorated halloysite nanotubes for the complete degradation of ornidazole via peroxymonosulfate activation
- 2023
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Ingår i: Journal of Colloid and Interface Science. - : Elsevier. - 0021-9797 .- 1095-7103. ; 630, s. 855-866
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Tidskriftsartikel (refereegranskat)abstract
- Peroxymonosulfate (PMS) driven by halloysite nanotubes (HNTs) modified with nanomanganese cobaltate (MnCo2O4) generates reactive oxygen species (ROS) that offer high degradation efficiency and mineralization rates for many typical antibiotic pollutants, such as ornidazole (ONZ). The experimental results show that halloysite nanotubes (HNTs) modified with nanomanganese cobaltate (MnCo2O4@HNTs denoted as MCO@HNTs) can degrade ONZ completely over a wide pH range (6.08–11.00) with little influence of the pH value. MCO@HNTs + PMS exhibited higher catalytic activity and lower Co- and Mn-ion leaching rates. It also showed a strong anti-interference effect on natural lake water and anions. Additionally, PMS can be quickly activated and consumed in natural lakes to avoid secondary pollution. The roasting of MCO@HNTs showed good catalytic activity and stability after degrading ONZ. The combination of ion quenching and electron paramagnetic resonance (EPR) analysis illustrated that the MCO@HNTs + PMS system had a strong oxidation capacity, and the produced singlet oxygen (1O2) was the main ROS for ONZ degradation. The degradation pathway of ONZ via the MCO@HNTs + PMS system was proposed based on the types of intermediates determined via liquid chromatography-mass spectrometry (LC-MS). This comprehensive study shows the preparation of a simple, environmentally friendly, and cheap PMS activation catalyst that has practical application value in the treatment of antibiotic wastewater and provides a focus on actual water testing with residual amount of PMS.
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