Facile fabrication of a biomass-based film with interwoven fibrous network structure as heterogeneous catalysis platform

Gallic acid-functionalized graphene hydrogel as adsorbent for removal of chromium (iii) and organic dye pollutants from tannery wastewater

“…[1][2][3] The chrome tanning mechanism is mainly based on coordination complexation between Cr(III) and deprotonated carboxyl groups of skin collagen under acidic (pH $ 4.0) conditions, which results in chemical cross-linking of collagen bers and conversion of rawhide to stable leather. [4][5][6] However, in the conventional chrome tanning process, only approximately 70% of the total chrome agent is absorbed by the leather, leading to accumulation of Cr(III) in tannery wastewater to concentrations higher than 3000 ppm. 7,8 In China, according to relevant laws, this chromium-containing tannery wastewater is prohibited from being directly discharged to waterways until the concentration of Cr(III) is reduced to lower than 10 ppm.…”

Facile fabrication of functional cellulose paper with high-capacity immobilization of Ag nanoparticles for catalytic applications for tannery wastewater

“…The largest peaks were observed from GA@AgNPs-LA-CP. Furthermore, compared to the XRD curves of CP samples without other crystal diffraction peaks, for both GA@AgNPs-CP and GA@AgNPs-LA-CP, The Bragg reflection peaks of 2θ arise at 33.5°, 46.4°, 66.8°, and 77.5°, which are coincident with the (1 1 1), (2 0 0), (2 2 0), and (3 1 1) facets of the face-centered cubic structure of crystalline Ag and indicate the immobilization of GA@AgNPs on cellulose fibers, respectively [41,48]. Lower peak intensities were observed in the GA@AgNPs-CP samples and most peaks were in similar locations.…”

“…However, virgin AgNPs tend to aggregate in the catalytic process, thus inhibiting its catalytic performance and practical application [39]. To overcome this shortcoming, the immobilization of silver nanoparticles on a support material has been considered as an effective method to improve the stability of AgNPs, which is conducive to maintaining the catalytic ability of AgNPs [40,41].…”

Preparation of Ag/C fiber with nanostructure through in situ thermally induced redox reaction between PVA and AgNO3 and its catalysis for 4‐nitrophenol reduction

“…Some of the main benefits of fibrous catalysts include the flexibility of form, low resistance to flow of gas and liquids through a bundle of fibers, high permeability due to their large specific surface area, safer operations, easy scale up, and reusability . In recent years, much effort has been focused on the development of effective strategies to incorporate Ag NPs within various fibers, such as natural fibers like collagen fibers and cellulose fibers and synthesized fibers such as carbon nanofibers, POM/PLLA electro‐spun fibers, alginate fibers, and PAN fibers . For the purpose of full exposure of catalytic Ag NPs, substantial effort has been directed towards uniform surface‐localized particles with various synthesized fibers with functional groups allowing effective chemical or physical interactions with the metal ions or formed NPs .…”

“…However, though the particles have been stabilized successfully using these techniques, the stabilization process could also cause loss in activity of the particles . It is found that Ag NPs are easily embedded into polymer fibers rather than dispersed onto the surface of fibers, but the presence of the polymer layers surrounding the Ag NPs usually weaken catalytic activity though limiting the interaction between the reactive species and the particle surface; therefore, the nanoparticles presented inside the substrate need to be easily accessible to various chemical reagents . Moreover, difficulty and toughness on homogeneously dispersion of nanoparticles for easy agglomeration of nanoparticles and the high viscosity of polymer solution are still challenged …”