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1.
J Colloid Interface Sci ; 645: 551-559, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37163801

RESUMO

Solar steam generation has attracted widespread attention because of its ability to produce clean water through desalination and wastewater treatment without conventional energy consumption. In this work, a polyaniline (PANI)-coated sodium alginate (SA)/cattail fiber (CF) foam for photothermal evaporator is prepared via directional freezing and oxidative polymerization. The SA/CF foam displays desirable water pumping capability because of the lamellar sandwich structure interconnected by porous networks. More importantly, the directional porous network architecture ameliorates the mechanical and salt-resistant performances of the SA/CF foam. The as-prepared PANI@SA/CF foam shows inferior heat conductivity of 0.047 W m-1 K-1 and outstanding light absorption over 96% in solar window. A vapor evaporation rate of 2.04 kg m-2 h-1 under 1 sun illumination is achieved for the PANI@SA/CF evaporator. Furthermore, the PANI@SA/CF foam could be employed in solar-driven freshwater generation from seawater and wastewater with high ion and dye removal rates. The combination of water evaporation and cleaning capabilities of the PANI@SA/CF foam as photothermal materials provide a framework for the exploration of next-generation evaporators in seawater desalination and wastewater treatment applications.

2.
J Pharm Anal ; 12(5): 791-800, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36320600

RESUMO

In this study, ecofriendly and economic carboxy-terminated plant fibers (PFs) were used as adsorbents for the effective in-syringe solid phase extraction (IS-SPE) of fluoroquinolone (FQ) residues from water. Based on the thermal esterification and etherification reaction of cellulose hydroxy with citric acid (CA) and sodium chloroacetate in aqueous solutions, carboxy groups grafted onto cotton, cattail, and corncob fibers were fabricated. Compared with carboxy-terminated corncob and cotton, CA-modified cattail with more carboxy groups showed excellent adsorption capacity for FQs. The modified cattail fibers were reproducible and reusable with relative standard deviations of 3.2%-4.2% within 10 cycles of adsorption-desorption. A good extraction efficiency of 71.3%-80.9% was achieved after optimizing the extraction condition. Based on carboxylated cattail, IS-SPE coupled with ultra-performance liquid chromatography with a photodiode array detector was conducted to analyze FQs in environmental water samples. High sensitivity with limit of detections of 0.08-0.25 µg/L and good accuracy with recoveries of 83.8%-111.7% were obtained. Overall, the simple and environment-friendly modified waste PFs have potential applications in the effective extraction and detection of FQs in natural waters.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-991105

RESUMO

In this study,ecofriendly and economic carboxy-terminated plant fibers(PFs)were used as adsorbents for the effective in-syringe solid phase extraction(IS-SPE)of fluoroquinolone(FQ)residues from water.Based on the thermal esterification and etherification reaction of cellulose hydroxy with citric acid(CA)and sodium chloroacetate in aqueous solutions,carboxy groups grafted onto cotton,cattail,and corncob fibers were fabricated.Compared with carboxy-terminated corncob and cotton,CA-modified cattail with more carboxy groups showed excellent adsorption capacity for FQs.The modified cattail fibers were reproducible and reusable with relative standard deviations of 3.2%-4.2%within 10 cycles of adsorption-desorption.A good extraction efficiency of 71.3%-80.9%was achieved after optimizing the extraction condition.Based on carboxylated cattail,IS-SPE coupled with ultra-performance liquid chromatography with a photodiode array detector was conducted to analyze FQs in environmental water samples.High sensitivity with limit of detections of 0.08-0.25 μg/L and good accuracy with recoveries of 83.8%—111.7%were obtained.Overall,the simple and environment-friendly modified waste PFs have potential appli-cations in the effective extraction and detection of FQs in natural waters.

4.
Bioresour Bioprocess ; 8(1): 101, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34760436

RESUMO

Vacuum-assisted resin transfer molding (VARTM), used in manufacturing medium to large-sized composites for transportation industries, requires non-woven mats. While non-woven glass mats used in these applications are optimized for resin impregnation and properties, such optimized mats for natural fibers are not available. In the current research, cattail fibers were extracted from plants (18-30% yield) using alkali retting and non-woven cattail fiber mat was manufactured. The extracted fibers exhibited a normal distribution in diameter (d avg. = 32.1 µm); the modulus and strength varied inversely with diameter, and their average values were 19.1 GPa and 172.3 MPa, respectively. The cattail fiber composites were manufactured using non-woven mats, Stypol polyester resin, VARTM pressure (101 kPa) and compression molding pressures (260 and 560 kPa) and tested. Out-of-plane permeability changed with the fiber volume fraction (V f) of the mats, which was influenced by areal density, thickness, and fiber packing in the mat. The cattail fibers reinforced the Stypol resin significantly. The modulus and the strength increased with consolidation pressures due to the increase in V f, with maximum values of 7.4 GPa and 48 MPa, respectively, demonstrating the utility of cattail fibers from waste biomass as reinforcements.

5.
Int J Biol Macromol ; 193(Pt A): 27-37, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34687763

RESUMO

Exploration of the application prospects of cattail fibers (CFs) in natural composites, and other fields is important for the sustainable development of new, green, light-weight, functional biomass materials. In this study, the physical and chemical properties, micro/nano structure, and mechanical characteristics of CFs were investigated. The CFs have a low density (618.0 kg m-3). The results of transmission electron microscopy and tensile testing data indicated that the cattail trunk fiber (CTF) bundle is composed of parenchyma cells and solid stone cells, demonstrating high specific modulus (10.1 MPa∙m3·kg-1) and high elongation at break (3.9%). In turn, the cattail branch fiber (CBF) bundle is composed of parenchyma cells with specific "half-honeycomb" shape. The inner diaphragms divide these cells into the open cavities. This structural feature endows the CTF bundles with stable structure, good oil absorption and storage capacities. The chemical component and the Fourier transform infrared spectroscopy analyses show that the CFs have higher lignin content (20.6%) and wax content (11.5%), which are conducive to the improvement of corrosion resistance, thermal stability and lipophilic-hydrophobic property of CF. Finally, the thermogravimetric analysis indicates that its final degradation temperature is 404.5 °C, which is beneficial to the increase in processability of CFs-reinforced composites.


Assuntos
Celulose , Nanoestruturas , Typhaceae , Celulose/química , Celulose/ultraestrutura , Interações Hidrofóbicas e Hidrofílicas , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Temperatura , Resistência à Tração , Typhaceae/química , Typhaceae/ultraestrutura
6.
Environ Technol ; 37(24): 3193-9, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27148643

RESUMO

Cattail fiber is considered as one of the biomasses for oil sorption purposes. In this work, the unique structure and wetting characteristic, as well as the basic mechanisms governing oil uptake of cattail fibers were investigated. Cattail fibers grow in tufts with down-like structure consisting of root, stem, seed and several fibers. A single cattail fiber was bamboo-shaped exhibiting 4-dimensional open spaces with fineness varying between 10 and 17.5 µm, average length at 7.9 ± 1.2 mm. The skeleton of the fiber consists of lignocellulose coated by a hydrophobic wax coating with 45.41% of crystallinity. The exceptional chemical, physical and microstructural properties enable the cattail fiber to be highly hydrophobic and oleophilic. The water droplets could stand on the fibers' surfaces with the contact angles more than 130°, while oil droplets disappear quickly from the fibers' surfaces within several seconds. When used as the sorbent for oil, cattail fibers were found to absorb about 12 g of oil per gram of fibers and retained over 88% of absorbed oil even after 24 h dripping. The unique structure of cattail fibers played an important role in oil sorption. The result proposed that cattail fibers are a promising natural source for the production of oil absorbents.


Assuntos
Óleos/química , Typhaceae , Poluentes Químicos da Água/química , Poluição da Água/prevenção & controle , Adsorção , Interações Hidrofóbicas e Hidrofílicas , Molhabilidade
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