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1.
Chemosphere ; 340: 139907, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37633615

RESUMO

Phosphorus-modified copper ferrite (P-CuFe2O4) nanoparticles were prepared by a simple sol-gel auto-combustion process and used for the photocatalytic ozonation of lomefloxacin (LOM). The morphology, crystallinity, and structure of the synthesized CuFe2O4 and P-CuFe2O4 nanoparticles were investigated using various techniques. The high-performance liquid chromatography (HPLC) analysis revealed that the degradation of LOM achieved a 99% reduction after a duration of 90 min in the photocatalytic ozonation system. In accordance with the charge-to-mass ratio, four intermediates were proposed with the help of their fragments obtained in LC-MS/MS. The degradation kinetics of lomefloxacin followed a pseudo-first order reaction, and the degradation mechanism was proposed based on the results. P0.035Cu0.965Fe2O4 showed the highest total organic carbon (TOC) removal with 20.15% in 90 min, highest specific surface area and the highest fluoride and ammonium production using the ion chromatography (IC). The experimental results obtained from the electron paramagnetic resonance (EPR) analysis indicated that the modified P-CuFe2O4 samples exhibited significantly elevated levels of superoxide (.O2-) production compared to the CuFe2O4 samples. The findings of this study demonstrate that the introduction of phosphorus modification into the copper ferrite photocatalyst led to an augmentation of both the specific surface area and the total pore volume. Furthermore, the incorporation of phosphorus served to promote the efficient separation of electron-hole pairs by effectively trapping electrons in the conduction band, hence enhancing the degradation efficiency.


Assuntos
Nanopartículas , Ozônio , Cromatografia Líquida , Cobre , Espectrometria de Massas em Tandem
2.
Int J Biol Macromol ; 204: 587-592, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35157905

RESUMO

Along with a water-soluble fraction rich in pectin, the hydrodynamic cavitation of citrus processing waste carried out in water demonstrated directly on semi-industrial scale affords an insoluble fraction consisting of micronized cellulose of low crystallinity ("CytroCell"). Lemon and grapefruit CytroCell respectively consist of 100-500 nm wide cellulose nanorods, and of 500-1000 nm wide ramified microfibrils extending for several µm. These findings establish a technically viable route to low crystallinity micronized cellulose laying in between nano- and microcellulose, using water and electricity only.


Assuntos
Citrus , Celulose , Eletricidade , Frutas , Água
3.
Sci Total Environ ; 790: 148081, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34091328

RESUMO

There exist several well-known methods with varying maturity for capturing carbon dioxide from emission sources of different concentrations, including absorption, adsorption, cryogenics and membrane separation, among others. The capture and separation steps can produce almost pure CO2, but at substantial cost for being conditioned for transport and final utilization, with high economical risks to be considered. A possible way for the elimination of this conditioning and cost is direct CO2 utilization, whether on-site in a further process but within the same plant, or in-situ, coupling both capture and conversion in the same unit. This approach is usually called integrated carbon capture and utilization (ICCU) or integrated carbon capture and conversion (ICCC), and has lately started receiving considerable attention in many circles. As CO2 is already industrially employed in other sectors, such as food preservation, water treatment and conversion to high added-value chemicals and fuels such as methanol, methane, etc., among others, it is of great interest to explore the global ICCC approach. Catalytic-based processes play a key role in CO2 conversion, and different technologies are gaining great attention from both academia and industry. However, the 'big picture of ICCU' and in which technology the efforts should focus on at large scale is still unclear. This review analyzes some promising concepts of ICCU specifically on CO2 catalytic conversion, highlighting their current commercial relevance as well as challenges that have to be faced today and in the next future.


Assuntos
Dióxido de Carbono , Metano , Catálise , Indústrias , Metanol
4.
Chemosphere ; 278: 130440, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33838416

RESUMO

In this paper, we present a critical review on antimicrobial nanomaterials with demonstrated potential for application as a disinfection technology in wastewater treatment. Studies involving fabrication and testing of antimicrobial nanomaterials for wastewater treatment were gathered, critically reviewed, and analyzed. Our review shows that there are only a few eligible candidate nanoparticles (NPs) (metal and metal oxide) that can adequately serve as an antimicrobial agent. Nanosilver (nAg) was the most studied and moderately understood metal NPs with proven antimicrobial activity followed by ZnO (among antimicrobial metal oxide NPs) which outperformed titania (in the absence of light) in efficacy due to its better solubility in aqueous condition. The direction of future work was found to be in the development of antimicrobial nanocomposites, since they provide more stability for antimicrobial metal and metal oxides NPs in water, thereby increasing their activity. This review will serve as an updated survey, yet touching also the fundamentals of the antimicrobial activity, with vital information for researchers planning to embark on the development of superior antimicrobial nanomaterials for wastewater treatment applications.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Purificação da Água , Antibacterianos , Óxidos
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