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Peculiarities of carbonization of two styrene/divinylbenzene precursors (one sulfonated, another aminated and phosphorylated)
have been investigated by thermogravimetry and differential thermal analysis. It was shown that phosphorus compounds incorporate
into carbon structure and cause delayed carbonization. Porous structure and surface properties of synthetic carbons have been
investigated by standard (BET, αs method, DA) and advanced (AED, PSD, regularization) methods from benzene and water adsorption isotherms. It was shown that
phosphorus-containing carbon is less microporous and shows highly hydrophilic surface.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
On the chemical structure of phosphorus compounds in phosphoric acid-activated carbon 总被引:1,自引:0,他引:1
Chemical structure of phosphorus species in polymer-based phosphoric acid-activated carbon SP800 was investigated by X-ray photoelectron spectroscopy. It has been shown that most probable structure for phosphorus species is condensed phosphates bound to carbon lattice via COP bonding. 相似文献
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Sodium titanium germanate with a semicrystalline framework (STG) of the formula Na3H(TiO)3(GeO)(GeO4)3·7H2O was synthesized under mild hydrothermal conditions and its proton form, H4(TiO)3(GeO)(GeO4)3·8H2O (STG-H), was prepared by acid treatment of the sodium compound. The STG was characterized by elemental analysis, TGA, FT-IR,
and X-ray powder diffraction. A comparative ion exchange examination of the STG-H towards alkali and alkaline earth metals
in a broad pH and concentration range was carried out. It was found that the STG is a moderately weak cation exchanger, possessing
high ion exchange capacity (up to 4.0 meq/g) and showing preference for heavy alkali and alkaline earth metals. The STG selectivity
towards Cs+ and Sr2+ ions in the presence of competitive metal ions and certain organic compounds was also studied. The data obtained suggest
that the sodium titanium germanate is a more selective exchanger for Sr2+ ion than its titanium silicate analogue, K3H(TiO)4(SiO4)3·4H2O. 相似文献
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The pore size distributions (PSD) of selected carbons were calculated from their nitrogen adsorption isotherms using both the QSDFT model implemented in ASiQwin version 3.0 software (Quantachrome Instruments) and 2D-NLDFT model implemented in SAIEUS software (Micromeritics). The results showed that both the QSDFT and the 2D-NLDFT methods give similar PSDs despite the different methods for accounting for the heterogeneity of the carbon adsorbent. The characteristic features of the methods and software were discussed and possible improvements were proposed. 相似文献
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Alexander M. Puziy Olga I. Poddubnaya Anna Derylo-Marczewska Adam W. Marczewski Magdalena Blachnio Mykola M. Tsyba Vitaliy I. Sapsay Dmytro O. Klymchuk 《Adsorption》2016,22(4-6):541-552
Kinetics of bovine serum albumin and ovalbumin adsorption by nanoporous carbons with different main pore sizes (1.6, 5, 7.8 and 28 nm) was studied. Experimental kinetics curves were well described by multi-exponential equation with different number of exponents (from 1 to 4). Protein adsorption kinetics showed significant dependence on pore size of carbonaceous adsorbent. Correlation between pore size distribution and amount of protein adsorbed revealed threshold pore size 7.3 nm for BSA and 6.8 nm for OVA, which are close to hydrodynamic diameter of protein molecules. The fastest and the highest adsorption of proteins were observed in carbons having developed porosity with pore sizes larger than 15 nm. 相似文献
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A.M. Puziy O.I. Poddubnaya M. Sobiesiak M.M. Tsyba M.I. Danylenko 《Applied Surface Science》2010,256(17):5216-219
Nanostructured carbons have been obtained by the template method using zeolite NaY and silica gels (SG60, Fluka and ZK, POCh) as structure directing agents. Texture and porous structure of carbons were characterized by TEM, XRD and nitrogen adsorption. Surface chemistry was investigated by the potentiometric titration method. It has been shown that all carbons show developed and uniform porous structure with mean size in the micropore range (1.1 nm) for zeolite derived carbon and in the mesopore range (3.4 and 4.8 nm) for silica gel derived carbons. The BET surface area of silica gel derived carbons is in the range 1230-1280 m2/g whereas zeolite derived carbon possesses very high BET surface area, 3000 m2/g. Potentiometric titration showed that carbons obtained by the template method contain significant amount of acid surface groups (carboxylic, lactone/enol and phenolic) with the total amount 1.1-1.5 mmol/g. To study adsorption-desorption properties of nanostructured carbons towards phenol and chlorophenols the solid phase extraction method was used. High recoveries of chlorophenols were obtained (80-93%) at the breakthrough volumes 1700-3000 mL. The recoveries are much higher than that obtained with commercially available carbon ACC (Supelco). 相似文献
8.
A. M. Puziy O. I. Poddubnaya A. Martínez-Alonso F. Surez-García J. M. D. Tascn 《Applied Surface Science》2002,200(1-4):196-202
The structural heterogeneity of synthetic phosphoric acid activated carbons has been analyzed using pore-size distributions (PSDs) obtained from nitrogen at −196 °C and carbon dioxide at 0 °C isotherms. PSDs where obtained by the BET–Kelvin method. It is shown that the BET–Kelvin method is in good agreement with DFT and provides a fast means for assessment of the porous structure of adsorbents. PSDs obtained by the BET–Kelvin method using different adsorbates give results consistent with each other. Due to the restricted pressure range for carbon dioxide adsorption isotherm the PSD gives information only about pores in the micropore range. The agreement between different methods is better for small micropores. 相似文献
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Shvalagin Vitaliy Ermokhina Natalia Romanovska Natalia Barakov Roman Manorik Petro Sapsay Vitaliy Shcherbakov Sergey Poddubnaya Olga Puziy Alexander 《Research on Chemical Intermediates》2019,45(8):4133-4148
Research on Chemical Intermediates - Mesoporous hierarchical TiO2 microspheres have been prepared using titanium alkoxide and crown ether as a structure-directing agent in combination with a small... 相似文献
10.
Phosphorus-containing carbons have been obtained by carbonization of porous copolymer of 4,4′-bis(maleimidodiphenyl)methane (50 mol%) and divinylbenzene (50 mol%) in presence of phosphoric acid at temperatures 400–1000 °C. Porous structure was analyzed by nitrogen adsorption isotherms while surface chemistry was investigated by potentiometric titration method. It has been shown that carbons obtained at 500–1000 °C are micro-mesoporous with pore sizes of 1–1.1, 2–3 and 5.4 nm. The most developed porosity was achieved at 600 °C reaching BET surface area 890 m2/g and total pore volume 0.45 cm3/g. Carbons obtained by carbonization of polyimide precursor in presence of phosphoric acid showed acidic character with 30–40 % of phosphate surface groups. Maximum total amount of acidic surface groups was achieved at 800 °C reaching 3.2 mmol/g. Assignment of strongly acidic surface groups to phosphates was corroborated by pK value, phosphorus content and thermal gravimetric analysis. 相似文献