Green acid-free hydrolysis of wasted pomelo peel to produce carboxylated cellulose nanofibers with super absorption/flocculation ability for environmental remediation materials

"Photo-catalytic degradation of organic dyes in aquatic environments under visible light irradiation affords an efficient and economic technique for environmental remediation. TEMPO-oxidized cellulose nanofibers/zinc oxide nanocomposite (TEMPO-CNF/ZnO) was prepared through oxidation of cellulose pulp, followed by zinc oxide precipitation in the presence of oxidized fibers. TEMPO-CNF/ZnO was characterized by different techniques. The degradation rate of methylene blue (MB) by TEMPO-CNF/ZnO was gradually increased with increasing pH and the degradation reached 86% within 340 minutes at pH 7. The kinetic study showed that the pseudo-first-order kinetic best fitted the photo-catalytic process. A mechanism was proposed for the degradation of MB using TEMPO-CNF/ZnO under visible light irradiation. TEMPO-CNF/ZnO showed high antibacterial activity against S. aureus and E. coli. Thus, the TEMPO-CNF/ZnO nanocomposite has been demonstrated to be an effective photo-catalytic material for degrading MB under visible light irradiation."

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Nanostructured Cellulose-Based Sorbent Materials for Water Decontamination from Organic Dyes

Nanomaterials ◽

10.3390/nano10081570 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1570 ◽

Cited By ~ 2

Author(s):

Laura Riva ◽

Nadia Pastori ◽

Alice Panozzo ◽

Manuela Antonelli ◽

Carlo Punta

Keyword(s):

Environmental Remediation ◽

Organic Dyes ◽

Cellulose Nanofibers ◽

Kinetic Studies ◽

Building Blocks ◽

Effective Removal ◽

Naphthol Blue Black ◽

New Material ◽

Branched Polyethylenimine ◽

Sorbent Materials

Nanostructured materials have been recently proposed in the field of environmental remediation. The use of nanomaterials as building blocks for the design of nano-porous micro-dimensional systems is particularly promising since it can overcome the (eco-)toxicological risks associated with the use of nano-sized technologies. Following this approach, we report here the application of a nanostructured cellulose-based material as sorbent for effective removal of organic dyes from water. It consists of a micro- and nano-porous sponge-like system derived by thermal cross-linking among (2,2,6,6-Tetramethylpiperidin-1-yl)oxyl (TEMPO)-oxidized cellulose nanofibers (TOCNF), branched polyethylenimine 25 kDa (bPEI), and citric acid (CA). The sorbent efficiency was tested for four different organic dyes commonly used for fabric printing (Naphthol Blue Black, Orange II Sodium Salt, Brilliant Blue R, Cibacron Brilliant Yellow), by conducting both thermodynamic and kinetic studies. The material performance was compared with that of an activated carbon, commonly used for this application, in order to highlight the potentialities and limits of this biomass-based new material. The possibility of regeneration and reuse of the sorbent was also investigated.

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Chirality-specific hydrolysis of amino acid substrates by cellulose nanofibers

Chemical Communications ◽

10.1039/c3cc44416c ◽

2013 ◽

Vol 49 (78) ◽

pp. 8827 ◽

Cited By ~ 19

Author(s):

Takeshi Serizawa ◽

Toshiki Sawada ◽

Masahisa Wada

Keyword(s):

Amino Acid ◽

Cellulose Nanofibers ◽

Hydrolysis Of

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Fine Structural Localization of Acyltransferases Involved in Lipid Synthesis in Intestinal Mucosa.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067261 ◽

1970 ◽

Vol 28 ◽

pp. 54-55

Author(s):

R. J. Barrnett ◽

J. A. Higgins

Keyword(s):

Smooth Endoplasmic Reticulum ◽

Lipid Synthesis ◽

Mucosal Cell ◽

Structural Localization ◽

Morphological Studies ◽

Mucosal Cells ◽

Initial Appearance ◽

Sh Group ◽

Hydrolysis Of ◽

Intestinal Mucosal Cells

The main products of intestinal hydrolysis of dietary triglycerides are free fatty acids and monoglycerides. These form micelles from which the lipids are absorbed across the mucosal cell brush border. Biochemical studies have indicated that intestinal mucosal cells possess a triglyceride synthesising system, which uses monoglyceride directly as an acylacceptor as well as the system found in other tissues in which alphaglycerophosphate is the acylacceptor. The former pathway is used preferentially for the resynthesis of triglyceride from absorbed lipid, while the latter is used mainly for phospholipid synthesis. Both lipids are incorporated into chylomicrons. Morphological studies have shown that during fat absorption there is an initial appearance of fat droplets within the cisternae of the smooth endoplasmic reticulum and that these subsequently accumulate in the golgi elements from which they are released at the lateral borders of the cell as chylomicrons.We have recently developed several methods for the fine structural localization of acyltransferases dependent on the precipitation, in an electron dense form, of CoA released during the transfer of the acyl group to an acceptor, and have now applied these methods to a study of the fine structural localization of the enzymes involved in chylomicron lipid biosynthesis. These methods are based on the reduction of ferricyanide ions by the free SH group of CoA.

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Lattice imaging and pore structure of β ferric oxyhydroxide

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108465 ◽

1978 ◽

Vol 36 (1) ◽

pp. 264-265

Author(s):

T. Baird ◽

J.R. Fryer ◽

S.T. Galbraith

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Bulk Material ◽

Model Structure ◽

Bulk Crystals ◽

Lattice Imaging ◽

Thin Sections ◽

Ferric Oxyhydroxide ◽

Resolution Electron ◽

Hydrolysis Of

Introduction Previously we had suggested (l) that the striations observed in the pod shaped crystals of β FeOOH were an artefact of imaging in the electron microscope. Contrary to this adsorption measurements on bulk material had indicated the presence of some porosity and Gallagher (2) had proposed a model structure - based on the hollandite structure - showing the hollandite rods forming the sides of 30Å pores running the length of the crystal. Low resolution electron microscopy by Watson (3) on sectioned crystals embedded in methylmethacrylate had tended to support the existence of such pores.We have applied modern high resolution techniques to the bulk crystals and thin sections of them without confirming these earlier postulatesExperimental β FeOOH was prepared by room temperature hydrolysis of 0.01M solutions of FeCl3.6H2O, The precipitate was washed, dried in air, and embedded in Scandiplast resin. The sections were out on an LKB III Ultramicrotome to a thickness of about 500Å.

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