Structural and adsorption studies of activated carbons derived from porous phenolic resins

Гунько, В.М.; Kozynchenko, O.P.; Туров, В.В.; Tennison, S.R.; Zarko, V.I.; Nychiporuk, Y.M.; Kulik, Tetiana; Palyanytsya, B.B.; Osovskii, V.D.; Ptushinskii, Yu.G.; Туров, А. В.

doi:10.1016/j.colsurfa.2007.11.006

Cited by 31 publications

(34 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Spherical porous particles of phenolformaldehyde resin (MAST Carbon Technology Ltd., Guildford, UK) [27] were carbonised in the CO 2 atmosphere at elevating temperature from ambient to 1073 K at a heating rate of 3 K/min (sample C-0) and additionally activated by CO 2 at 1173 K at 47% burn-off (sample C-47) [28]. Carbon particle size was 0.15-0.50 mm.…”

Section: Methodsmentioning

confidence: 99%

Characteristics of adsorption phase with water/organic mixtures at a surface of activated carbons possessing intraparticle and textural porosities

Гунько

Туров

Kozynchenko

et al. 2008

Applied Surface Science

Self Cite

View full text Add to dashboard Cite

Section: Methodsmentioning

confidence: 99%

Characteristics of adsorption phase with water/organic mixtures at a surface of activated carbons possessing intraparticle and textural porosities

Гунько

Туров

Kozynchenko

et al. 2008

Applied Surface Science

Self Cite

View full text Add to dashboard Cite

“…Three proteins different in size and shape: BSA (67 kDa), human serum fibrinogen, Fg (340 kDa), and aprotinin (basic (bovine) pancreatic tripsin inhibitor, BPTI, 6.7 kDa) were used in the diffusion experiments with collagen hydrogel membranes (type I bovine tendon collagen crosslinked by glycosaminoglycan, GAG), an inner layer from INTEGRA TM bilayer matrix wound dressing [106,195]. Both BPTI and BSA are globular proteins, but of different sizes, whilst Fg is a much larger rod-like protein (Fig.…”

Section: Diffusion Of Small Molecules Polymers Proteins and Cells Wmentioning

confidence: 99%

“…40) was due to the difference in the PSDs (Fig. 13a), contribution of narrow and middle nanopores (Table 4), the concentration of active surface sites related to the burn-off degree [195] and additional activation of C-7 in air. These factors as well as the difference in the chemical structure and charge of dye molecules ( (Fig.…”

mentioning

confidence: 99%

Cryogels: Morphological, structural and adsorption characterisation

Gun'ko

Savina

Mikhalovsky

2013

Advances in Colloid and Interface Science

286

205

View full text Add to dashboard Cite

*Graphical Abstract (for review)Cryotripic gelation technique allows the synthesis of solid and soft macroporous gels Textural characterisation of cryogel in native superhydrated state with noninvasive methods Adsorption and diffusion characteristics of macroporous cryogels with respect to macromolecules and cells Theoretical modelling of adsorption from aqueous media *Highlights (for review) Please find the revised manuscript entitled "Cryogels: morphological, structural and adsorption characterisation" by Vladimir M. Gun'ko, Irina N. Savina, Sergey V. Mikhalovsky to re-consider for publication in the "Advances in Colloid and Interface Science"The paper was completely edited and changed according to reviewers comments.Sincerely yours, Prof. V. M. Gun'koCover Letter ABSTRACTExperimental results on polymer, protein, and composite cryogels and data treatment methods used for morphological, textural, structural, adsorption and diffusion characterisation of the materials are analysed and compared. Treatment of microscopic images with specific software gives quantitative structural information on both native cryogels and freeze-dried materials that is useful to analyse the drying effects on their structure. A combination of cryoporometry, relaxometry, thermoporometry, small angle X-ray scattering (SAXS), equilibrium and kinetic adsorption of low and high-molecular weight compounds, diffusion breakthrough of macromolecules within macroporous cryogel membranes, studying interactions of cells with cryogels provides a consistent and comprehensive picture of textural, structural and adsorption properties of a variety of cryogels. This analysis allows us to establish certain regularities in the cryogel properties related to narrow (diameter 0.4 < d < 2 nm), middle (2 < d < 50 nm) and broad (50 < d < 100 nm) nanopores, micropores (100 nm < d < 100 m) and macropores (d > 100 m) with boundary sizes within modified life science pore classification. Particular attention is paid to water bound in cryogels in native superhydrated or freeze-dried states. At least, five states of water -free unbound, weakly bound (changes in the Gibbs free energy G < 0.5-0.8 kJ/mol) and strongly bound (G > 0.8 kJ/mol), and weakly associated (chemical shift of the proton resonance  H = 1-2 ppm) and strongly associated ( H = 3-6 ppm) waters can be distinguished in hydrated cryogels using 1 H NMR, DSC, TSDC, TG and other methods. Different software for image treatment or developed to analyse the data obtained with the adsorption, diffusion, SAXS, cryoporometry and thermoporometry methods and based on regularisation algorithms is analysed and used for the quantitative morphological, structural and adsorption characterisation of individual and composite cryogels, including polymers filled with solid nano-or microparticles.

show abstract

“…In order for the Novolac resin to become a hard, thermosetting resin during heat-treatment, it requires a solvent that also acts as a cross-linking agent. The most common curing agent is hexamethylenetetramine (HMTA) or "hexamine" which forms methylene and dimethylene amino bridges to generate a three-dimensional reticulated structure at temperatures ≥180 °C (Gun'ko, Kozynchenko et al 2008). …”

Section: Materials and Characterisationmentioning

confidence: 99%

“…CMSs have been derived from different precursors, including the pyrolysis of polymeric materials such as polyfurfuryl alcohol (PFA) , polyvinylidene chloride (PVDC) , polyimides , and phenolic resin Wei, Hu et al 2002;Zhang, Hu et al 2006;Wei, Qin et al 2007;Zhang, Hu et al 2007;Gun'ko, Kozynchenko et al 2008;Teixeira, Campo et al 2011). The organic precursor and the pyrolisation process deliver carbon with different structures and functionalities.…”

Section: Introductionmentioning

confidence: 99%

Carbon molecular sieve membranes for desalination

Song¹

View full text Add to dashboard Cite

i This work reports on the development of novel carbon molecular sieve (CMS) membranes for desalination. The membranes were prepared by vacuum impregnation of precursor solutions containing phenolic resin into porous alumina tubes. Subsequently, the membrane tubes were calcined in an inert atmosphere, leading to the carbonisation of the resin impregnated into the porous alumina substrate. A systematic and parametric study was undertaken to investigate the effect of: (i) substrate porosity, (ii) precursor solution, (iii) vacuum impregnation time and (iv) carbonisation temperature on the performance of the resultant membranes. AbstractHigh quality CMS membranes were successfully prepared. High water fluxes were achieved using a pervaporation setup with values of 27 kg m -2 h -1 observed at 75 °C whilst delivering salt rejection in excess of 96% for a synthetic aqueous solution of 0.3 wt% NaCl chosen to represent brackish water. Increasing the salt concentration resulted in the water flux reducing, which was most likely due to salt concentration polarisation. However, the CMS membranes continued to perform well for processing sea water (3.5 wt% NaCl) at room temperature delivering water fluxes in the region of 9.4 kg m -2 h -1 with a salt rejection close to 100%. The high performance given by the CMS membranes in terms of water fluxes are at least one order of magnitude higher than those reported for other inorganic membranes derived from silica or zeolites.One important finding of this work is that the water flux increased by a factor of 70 as the concentration of the phenolic resin precursor solution decreased from 40 to 1 wt%. This result indicates that high resin concentration led to a higher amount of carbonised resin in the porous substrate and a higher resistance to water diffusion. The precursor solutions with a low resin concentration allowed for the formation of ideal CMS structures, which polymerised into the interparticle pore domains of the porous alumina substrate. As such a molecular sieving structure was formed as it preferentially allowed for the diffusion of the smaller molecule water with a kinetic diameter of 2.6 Å, and to a higher degree rejected the passage of hydrated ions with sizes in excess of 7 Å.A second important finding is that the functionality of the carbonised resin plays a role in delivering CMS membranes with high performance. CMS materials carbonised at 500 °C still retained some functional aromatic groups which were hydrophilic and impacted on membrane performance.However, increasing the carbonisation temperature to 700 °C lead to optimal microporosity, enhanced surface area and reduced hydrophilicity as the functional groups were almost completely ii removed. Further increases of carbonisation temperature to 800 °C resulted in the formation of larger, mesoporous structures and the unfavourable reduction of salt rejection.A third important finding is that best CMS membranes were prepared by longer vacuum times of 300 to 600 s, instead of short times of 30 or 60 s. This result wa...

show abstract

Structural and adsorption studies of activated carbons derived from porous phenolic resins

Cited by 31 publications

References 41 publications

Characteristics of adsorption phase with water/organic mixtures at a surface of activated carbons possessing intraparticle and textural porosities

Characteristics of adsorption phase with water/organic mixtures at a surface of activated carbons possessing intraparticle and textural porosities

Cryogels: Morphological, structural and adsorption characterisation

Carbon molecular sieve membranes for desalination

Contact Info

Product

Resources

About