Impact of poly(vinyl alcohol) adsorption on the surface characteristics of mixed oxide Mn x O y –SiO2

Wiśniewska, Małgorzata; Bogatyrov, V. M.; Ostolska, Iwona; Szewczuk-Karpisz, Katarzyna; Terpiłowski, Konrad; Nosal‐Wiercińska, Agnieszka

doi:10.1007/s10450-015-9696-2

Cited by 36 publications

(21 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Manganese (IV) oxide (MnO 2 ) is ubiquitous in natural environments and exhibits versatility in regulating the mobility and environmental fate of contaminants through adsorption, abiotic oxidation, catalytic transformation, or photochemical processes (Wisniewska et al 2015;Omorogie et al 2015;Elzinga et al 2011). Due to its capacity for high-efficiency, environmentally friendly pollutant control, MnO 2 usually has been applied in the removal of heavy metals (Andjelkovic et al 2013), antibiotics, and dyes (Chen and He 2008).…”

Section: Introductionmentioning

confidence: 99%

Highly efficient removal of methylene blue from aqueous solution by a novel fishing-net effect of manganese oxide nano-sheets

Peng

Liu

Zeng

et al. 2016

Clean Techn Environ Policy

View full text Add to dashboard Cite

Manganese (IV) oxide (MnO 2 ) nano-sheets were synthesized using tetramethylamine, H 2 O 2 , and MnCl 2 Á4H 2 O and used in suspension for removal of methylene blue (MB). Up to 95 % removal was achieved for MB concentrations less than 500 mg/L. The adsorption data fitted better with the Freundlich isotherm model than the Langmuir model, indicating a heterogeneous adsorption of MB on MnO 2 nano-sheets. The maximum adsorption capacity of MnO 2 nano-sheets was approximately 4300 mg/g, which is the highest yet reported. Suspensions of MnO 2 nano-sheets aggregated as precipitates after adsorption of MB. Using a suite of analyses, including X-ray diffraction and X-ray photoelectron spectroscopy, the high adsorption capacity was mainly attributed to ion exchange, coordination, and a fishing-net effect. The term, 'fishing-net effect,' is proposed here for the first time, to explain the extremely high adsorption capacity of nano-sheets, which increased with increasing ionic strength and sorbate concentration. Our results demonstrate that dispersive MnO 2 nano-sheets have a potential application in adsorption of organics from strongly basic solutions with high salinity.

show abstract

Section: Introductionmentioning

confidence: 99%

Highly efficient removal of methylene blue from aqueous solution by a novel fishing-net effect of manganese oxide nano-sheets

Peng

Liu

Zeng

et al. 2016

Clean Techn Environ Policy

View full text Add to dashboard Cite

show abstract

“…Therefore, metal oxides are often characterized by small specific surface area, and consequently, they could be modified by several treatments in order to obtain better adsorption properties. For example, Mn x O y -SiO 2 mixed oxides materials show better textural properties and adsorption affinity than manganese oxides, exhibiting higher adsorption capacity [7].…”

Section: Introductionmentioning

confidence: 99%

Enhancement of p-nitrophenol adsorption capacity through N2-thermal-based treatment of activated carbons

Álvarez-Torrellas

Martin-Martinez

Gomes

et al. 2017

Applied Surface Science

View full text Add to dashboard Cite

In this work several activated carbons showing different textural and chemical properties were obtained by chemical and physical activation methods, using a lignocellulosic material (peach stones) as precursor. The activated carbon resulting from the chemical activation, namely as CAC, revealed the best textural properties (S BET = 1521 m 2 g −1 , pore volume = 0.90 cm 3 g −1) and an acidic character. It was found that the activated carbon obtained at 300 • C (under air atmosphere, PAC air), and those synthesized at 750 • C in presence of N 2 flow with bubbling of water/12 M H 3 PO 4 solution (PAC N 2 (H 2 O)/PAC N 2 (H 3 PO 4)), respectively, revealed worse textural properties, compared to CAC. Two functionalization treatments, by using sulphuric acid at boiling temperature (PACS) and nitric acid-urea-N 2 heating at 800 • C (PAC-NUT), were applied to PAC air, in order to enhance the adsorption ability of the carbon material. Several techniques were carried out to characterize the physical and chemical properties of the obtained carbon materials. The modification treatments had influence on the carbon surface properties, since the nitric acidurea-N 2 heating treatment led to a carbon material with highly-improved properties (S BET = 679 m 2 g −1 , pH IEP = 5.3). Accordingly, the original and modified-carbon materials were tested as adsorbents to remove 4nitrophenol (4-NP), assessing batch and fixed-bed column adsorption tests. PAC-NUT carbon offered the best adsorption behavior (q e = 234 mg g −1), showing a high ability for the removal of 4-NP from water.

show abstract

“…Thus, the degree of carvacrol retention would depend not only on liposomal encapsulation systems, but also on the interaction of the active compound released with the polymer matrix. P-PVA has residual acetyl groups (12%) in the polymer chain, which acquire a state of resonance and provide the matrix with a negative charge [ 48 ]. This donor electron pair provides the P-PVA chains with the Lewis base character, which promotes the formation of Lewis adducts with carvacrol (Lewis acid).…”

Section: Resultsmentioning

confidence: 99%

“…This donor electron pair provides the P-PVA chains with the Lewis base character, which promotes the formation of Lewis adducts with carvacrol (Lewis acid). This mechanism enhances the chemical affinity between carvacrol and the polymer chains, increasing their retention in the film [ 5 , 48 , 49 ]. In this sense, it was possible to observe that the type of lecithin had less influence on the CA retention for P-PVA matrices, since the carvacrol released from liposomes could be better entrapped through its bonding to the P-PVA chains.…”

Section: Resultsmentioning

confidence: 99%

Liposomal Encapsulation of Carvacrol to Obtain Active Poly (Vinyl Alcohol) Films

Andrade

González‐Martínez

2021

Molecules

View full text Add to dashboard Cite

Lecithins of different origins and compositions were used for the liposomal encapsulation of carvacrol within the framework of the development of active films for food packaging. Liposomes were incorporated into aqueous polymeric solutions from fully (F) and partially (P) hydrolysed Poly (vinyl alcohol) (PVA) to obtain the films by casting. The particle size distribution and ζ-potential of the liposomal suspensions, as well as their stability over time, were evaluated. Liposomal stability during film formation was analysed through the carvacrol retention in the dried film and the film microstructure. Subtle variations in the size distributions of liposomes from different lecithins were observed. However, the absolute values of the ζ-potential were higher (−52, −57 mV) for soy lecithin (SL) liposomes, followed by those of soy lecithin enriched with phosphatidylcholine (SL-PC) (−43, −50 mV) and sunflower lecithin (SFL) (−33, −38 mV). No significant changes in the liposomal properties were observed during the study period. Lyotropic mesomorphism of lipid associations and carvacrol leakage occurred to differing extents during the film drying step, depending on the membrane lipid composition and surface charge. Liposomes obtained with SL-PC were the most effective at maintaining the stability of carvacrol emulsion during film formation, which led to the greatest carvacrol retention in the films, whereas SFL gave rise to the least stable system and the highest carvacrol losses. P-PVA was less sensitive to the emulsion destabilisation due to its greater bonding capacity with carvacrol. Therefore, P-PVA with carvacrol-loaded SL-PC liposomes has great potential to produce active films for food packaging applications.

show abstract

Impact of poly(vinyl alcohol) adsorption on the surface characteristics of mixed oxide Mn x O y –SiO2

Cited by 36 publications

References 28 publications

Highly efficient removal of methylene blue from aqueous solution by a novel fishing-net effect of manganese oxide nano-sheets

Highly efficient removal of methylene blue from aqueous solution by a novel fishing-net effect of manganese oxide nano-sheets

Enhancement of p-nitrophenol adsorption capacity through N2-thermal-based treatment of activated carbons

Liposomal Encapsulation of Carvacrol to Obtain Active Poly (Vinyl Alcohol) Films

Contact Info

Product

Resources

About