APPARENT DENSITIES AND INTERNAL SURFACE AREAS OF SELECTED CARBON BLACKS

1962 ◽  
Vol 40 (2) ◽  
pp. 184-188 ◽  
Author(s):  
P. L. Walker Jr. ◽  
W. V. Kotlensky
Keyword(s):  
Surface Area ◽  
Pore Diameter ◽  
Internal Surface ◽  
Nitrogen Adsorption ◽  
Roughness Factor ◽  
Internal Surface Area ◽  
Average Pore ◽  
Carbon Blacks ◽  
Surface Areas ◽  
Nitrogen Adsorption Isotherms

It is shown that the open pore volume within carbon blacks can be calculated from nitrogen adsorption isotherms (77°K) on the blacks. From this volume and a helium density, the apparent density of a black can be calculated. Other properties of the blacks which then can be calculated are free surface area, internal surface area, surface roughness factor, and the average pore diameter of the internal surface. These data are presented for five selected carbon blacks.

PERMEABILITY STUDIES: III. SURFACE AREA MEASUREMENTS OF CARBON BLACKS

1948 ◽  
Vol 26a (2) ◽  
pp. 29-38 ◽  
Author(s):  
J. C. Arnell ◽  
G. O. Henneberry
Keyword(s):  
Electron Microscope ◽  
Low Temperature ◽  
Carbon Black ◽  
Surface Area ◽  
Satisfactory Agreement ◽  
Nitrogen Adsorption ◽  
Average Particle ◽  
Carbon Blacks ◽  
Permeability Studies ◽  
Nitrogen Adsorption Isotherms

The modified Kozeny equation has been found to be satisfactory for the measurement of the specific surfaces of carbon blacks having average particle diameters ranging from 0.01 to 0.1 μ to within ±10%. Comparative data were obtained from electron microscope counting and from low temperature nitrogen adsorption isotherms. The three methods examined gave results that were in satisfactory agreement, except when the carbon black was porous, and then the adsorption value was extremely large.

Nano/Micro Pore Structure and Fractal Characteristics of Baliancheng Coalfield in Hunchun Basin

2021 ◽  
Vol 21 (1) ◽  
pp. 682-692
Author(s):  
Youzhi Wang ◽  
Cui Mao
Keyword(s):  
Fractal Dimension ◽  
Specific Surface ◽  
Pore Structure ◽  
Surface Area ◽  
Specific Surface Area ◽  
Pore Diameter ◽  
Fractal Dimensions ◽  
Nitrogen Adsorption ◽  
Average Pore ◽  
Coal Reservoir

The pore structure characteristic is an important index to measure and evaluate the storage capacity and fracturing coal reservoir. The coal of Baliancheng coalfield in Hunchun Basin was selected for experiments including low temperature nitrogen adsorption method, Argon Ion milling Scanning Electron Microscopy (Ar-SEM), Nuclear Magnetic Resonance (NMR), X-ray diffraction method, quantitative mineral clay analysis method. The pore structure of coal was quantitatively characterized by means of fractal theory. Meanwhile, the influences of pores fractal dimension were discussed with experiment data. The results show that the organic pores in Baliancheng coalfield are mainly plant tissue pores, interparticle pores and gas pores, and the mineral pores are corrosion pores and clay mineral pores. There are mainly slit pore and wedge-shaped pore in curve I of Low temperature nitrogen adsorption. There are ink pores in curve II with characteristics of a large specific surface area and average pore diameter. The two peaks of NMR T2 spectrum indicate that the adsorption pores are relatively developed and their connectivity is poor. The three peaks show the seepage pores and cracks well developed, which are beneficial to improve the porosity and permeability of coal reservoir. When the pore diameter is 2–100 nm, the fractal dimensions D1 and D2 obtained by nitrogen adsorption experiment. there are positive correlations between water content and specific surface area and surface fractal dimension D1, The fractal dimension D2 was positively and negatively correlated with ash content and average pore diameters respectively. The fractal dimensions DN1 and DN2 were obtained by using the NMR in the range of 0.1 μm˜10 μm. DN1 are positively correlated with specific surface area of adsorption pores. DN2 are positively correlated volume of seepage pores. The fractal dimension DM and dissolution hole fractal dimension Dc were calculated by SEM image method, respectively controlled by clay mineral and feldspar content. There is a remarkable positive correlation between D1 and DN1 and Langmuir volume of coal, so fractal dimension can effectively quantify the adsorption capacity of coal.

Carbon Black Surface Areas by the Harkins and Jura Absolute Method

1967 ◽  
Vol 40 (5) ◽  
pp. 1305-1310 ◽  
Author(s):  
G. Kraus ◽  
K. W. Rollmann
Keyword(s):  
Particle Size ◽  
Carbon Black ◽  
Surface Area ◽  
Nitrogen Adsorption ◽  
Absolute Method ◽  
Carbon Blacks ◽  
Surface Areas ◽  
Particle Size Determination ◽  
Light Reflectance ◽  
Adsorption Surface

Abstract The Harkins and Jura (HJ) absolute method of surface area determination (Harkins and Jura, J. Am. Chem. Soc. 66, 919, 1944) has been applied to a large number of carbon blacks. Surface area is calculated from the heat of immersion of the solid powder covered by a preadsorbed multilayer of the immersion liquid. For non-porous carbon blacks good agreement with nitrogen adsorption surface areas is obtained, but with porous blacks the HJ method gives smaller values since micropores are filled and bridged over by the pre-adsorbed film. Thus the HJ areas are more nearly representative of particle size and may be used to calibrate indirect methods of particle size determination. An example of this is shown using light reflectance values on dry carbon black and possible complications due to particle size distribution in the use of the reflectance test are discussed.

Surface Area of Nonporous Carbon Blacks and Area of the Adsorbed Nitrogen Molecule

1964 ◽  
Vol 37 (3) ◽  
pp. 630-634 ◽  
Author(s):  
Andries Voet
Keyword(s):  
Surface Area ◽  
Nitrogen Adsorption ◽  
Nitrogen Molecule ◽  
Adsorption Method ◽  
Chain Formation ◽  
Electron Micrography ◽  
Carbon Blacks ◽  
Surface Areas ◽  
Particle Chain ◽  
Lower Ratio

Abstract Surface areas of completely nonporous carbon blacks of widely varying particle chain formation (structure) have been determined by means of the nitrogen adsorption method as well as by electron micrography. Accurately determined densities in helium were used as the basis of calculations in the latter approach. It was found that the ratio of areas measured by nitrogen adsorption to electron micrographically determined surface areas is greatly dependent upon chain formation. A higher structural build-up leads to a lower ratio, explained by the observation that fusion areas in carbon chains are necessarily, though erroneously, counted as surfaces in electron micrography. The ratio differs markedly from unity, however, in low structure blacks, where fusion areas are negligible. By accepting the area of a nitrogen molecule adsorbed in a monolayer as being equal to that in the solid state, 13.8 A2, the ratio becomes unity for nonporous low structure blacks. It appears likely, therefore, that all surface area data based on the area of a nitrogen molecule in the liquid state of 16.2 A2 are too high by about 15 per cent of presently accepted values.

scholarly journals Sorption of Methylene Blue for Studying the Specific Surface Properties of Biomass Carbohydrates

Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1115
Author(s):  
Tatiana Skripkina ◽  
Ekaterina Podgorbunskikh ◽  
Aleksey Bychkov ◽  
Oleg Lomovsky
Keyword(s):  
Methylene Blue ◽  
Specific Surface ◽  
Surface Area ◽  
Surface Characterization ◽  
Gas Adsorption ◽  
Comparative Method ◽  
Nitrogen Adsorption ◽  
Surface Areas ◽  
Nitrogen Adsorption Isotherms ◽  
Adsorption Desorption

The surface area is an important parameter in setting any biorefining technology. The aim of this study was to investigate the applicability of sorption of methylene blue to characterize the surface of the main biomass carbohydrates: α-cellulose, sigmacell cellulose, natural gum, β-glucan, and starch. The morphology of particles of the model objects was studied by scanning electron microscopy. Nitrogen adsorption isotherms demonstrate that the selected carbohydrates are macroporous adsorbents. The monolayer capacities, the energy constants of the Brunauer–Emmett–Teller (BET) equation, and specific surface areas were calculated using the BET theory, the comparative method proposed by Gregg and Sing, and the Harkins–Jura method. The method of methylene blue sorption onto biomass carbohydrates was adapted and mastered. It was demonstrated that sorption of methylene blue proceeds successfully in ethanol, thus facilitating surface characterization for carbohydrates that are either soluble in water or regain water. It was found that the methylene blue sorption values correlate with specific surface area determined by nitrogen adsorption/desorption and calculated from the granulometric data. As a result of electrostatic attraction, the presence of ion-exchanged groups on the analyte surface has a stronger effect on binding of methylene blue than the surface area does. Sorption of methylene blue can be used in addition to gas adsorption/desorption to assess the accessibility of carbohydrate surface for binding large molecules.

SURFACE CHEMISTRY AND CATALYTIC PROPERTIES OF BORON PHOSPHATE: 1. SURFACE AREA AND ACIDITY

1965 ◽  
Vol 43 (6) ◽  
pp. 1680-1688 ◽  
Author(s):  
J. B. Moffat ◽  
H. L. Goltz
Keyword(s):  
Surface Area ◽  
Active Sites ◽  
Elevated Temperatures ◽  
Catalytic Properties ◽  
Nitrogen Adsorption ◽  
Weight Changes ◽  
Kcal Mole ◽  
Boron Phosphate ◽  
Surface Areas ◽  
Nitrogen Adsorption Isotherms

Surface properties of the dehydration catalyst, boron phosphate (BP), prepared by the reaction of triethyl borate and phosphoric acid, were investigated by the use of a microbalance system. During evacuation at elevated temperatures, weight changes of the BP were obtained. Nitrogen adsorption isotherms were measured after each treatment. Surface areas appear to increase, and reach a maximum in the range 200–300 °C. Weight changes are initially large but begin to level off as the temperature is increased. Ammonia isotherms were obtained at 25.00 °C on aliquots of the same BP sample after various pretreatments. Amounts of ammonia remaining adsorbed after evacuation overnight were taken as the quantity chemisorbed. An approximate value of 8.9 kcal/mole of ammonia was obtained for the heat of chemisorption of ammonia by measuring the pressure and weight change as the amount of chemisorbed ammonia is decreased on heating the BP to various temperatures in a closed system. Results are interpreted in terms of change of number of active sites with surface area and the deactivation of sites on loss of water.

Immobilization of cationic zinc(II) complexes of phthalocyanine and unsymmetrical porphyrazine in mesoporous MCM-41 silica, and photo-catalytic activity of the composites

2006 ◽  
Vol 10 (10) ◽  
pp. 1212-1218 ◽  
Author(s):  
Kuninobu Kasuga ◽  
Makoto Imai ◽  
Hiroyuki Irie ◽  
Hidekazu Tanaka ◽  
Takashi Ikeue ◽  
...  
Keyword(s):  
Reaction Rate ◽  
Pore Diameter ◽  
Nitrogen Adsorption ◽  
Initial Reaction Rate ◽  
Initial Reaction ◽  
Photo Catalytic Activity ◽  
Surface Areas ◽  
Specific Surface Areas ◽  
Nitrogen Adsorption Isotherms ◽  
Mcm 41

Cationic 2,9,16,23-tetrakis(3- N , N , N -trimethylaminoethyloxy)phthalocyaninatozinc(II) and 20,21-bis(4- N , N , N -trimethylaminophenyl)-4,5,9,10,14,15-hexakis(4-t-butylphenyl)porphyrazinatozinc(II) were immobilized in MCM-41 silica by the use of an electrostatic interaction with the deprotonated silanol groups of MCM-41. From nitrogen adsorption isotherms, specific surface areas were estimated as 1031 and 702 m2.g−1 for MCM-41 and the composite of 2,9,16,23-tetrakis(3- N , N , N -trimethylaminoethyloxy)phthalocyaninatozinc(II), respectively. From pore-size distribution curves, the maximum pore diameter of MCM-41 and the composite were also estimated as 3.24 and 3.10 nm, respectively. These results revealed that 2,9,16,23-tetrakis(3- N , N , N -trimethylaminoethyloxy)phthalocyaninatozinc(II) was immobilized in the mesopores of MCM-41. While 2,9,16,23-tetrakis(3- N , N , N -trimethylaminoethyloxy)phthalocyaninatozinc(II) formed a dimer with increase in the amount of the complex in the composite, 20,21-bis(4- N , N , N -trimethylaminophenyl)-4,5,9,10,14,15-hexakis(4-t-butylphenyl)porphyrazinatozinc(II) only slightly formed a dimer in the composite, due to steric hindrance of its peripheral substituents. 1,3-diphenylisobenzofuran was photo-oxidized using the composites as the sensitizer in aerated acetonitrile. The reaction proceeded with singlet dioxygen generated by visible-light irradiation of the sensitizers. While the initial reaction rate with the composite of 20,21-bis(4- N , N , N -trimethylaminophenyl)-4,5,9,10,14,15-hexakis(4-t-butylphenyl)porphyrazinatozinc(II) increased in proportion to the increase in the amount of the complex, the initial reaction rate with the composite of 2,9,16,23-tetrakis(3- N , N , N -trimethylaminoethyloxy)phthalocyaninatozinc(II) at first increased, but subsequently decreased due to the formation of the photo-inactive dimer.

scholarly journals Thermogravimetric analysis of Ontario limestones and dolomites I. Calcination, surface area, and porosity

1970 ◽  
Vol 48 (19) ◽  
pp. 2972-2978 ◽  
Author(s):  
R. K. Chan ◽  
K. S. Murthi ◽  
D. Harrison
Keyword(s):  
Calcium Carbonate ◽  
Thermogravimetric Analysis ◽  
Surface Area ◽  
Pore Diameter ◽  
Nitrogen Adsorption ◽  
Magnesium Carbonate ◽  
Type Ii ◽  
Nitrogen Adsorption Isotherm ◽  
Mercury Intrusion ◽  
Surface Areas

The calcination of natural Ontario limestones and dolomites in a flow of 100 cm3/min of nitrogen at 745 °C required from 0.43 ± 0.03 to 0.35 ± 0.05 min/mg of 100 mesh samples, respectively. The nitrogen adsorption isotherm at 77 °K for all the calcined samples belonged to the type II isotherm of the B.D.D.T. classification. There was hardly any hysteresis between the adsorption and desorption branches which implied that most of the pores were relatively large in agreement with independent measurements of the most probable pore diameter by an Aminco mercury intrusion porosimeter (~ 0.1 μ). The B.E.T. surface areas ranged from 13.6 to 34.2 m2/g of oxide calcined at 745 °C. The surface area decreased rapidly with increasing calcination temperature. At 1090 °C the surface area was less than 1 m2/g. The surface area was also related to percentage calcination, percentage calcium oxide in the sample, and size of the sample. A sample of pure magnesium carbonate calcined at 565 °C had an inordinately large surface area of 174 m2/g; pure calcium carbonate calcined at 745 °C, 15.2 m2/g. Using a model of non-intersecting cylindrical or square capillaries for the pore configurations, one could calculate the surface area, porosity, and bulk density of the calcined samples with satisfactory agreement.

scholarly journals Investigation on the Deterioration Mechanism of Recycled Plaster

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Zhixin Li ◽  
Kaidong Xu ◽  
Jiahui Peng ◽  
Jina Wang ◽  
Xianwei Ma ◽  
...  
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Pore Diameter ◽  
Nitrogen Adsorption ◽  
Water Requirement ◽  
Scanning Calorimetry ◽  
Average Pore ◽  
Preparation Temperature ◽  
Deterioration Mechanism

The deterioration mechanism of recycled plaster (R-P) was studied. The large specific surface area (SSA), improper preparation temperature, increased water requirement of R-P, and microstructure of its hardened body were analyzed by particle size distribution (PSD), Blaine method, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and nitrogen adsorption porosimetry. The results indicated that the properties of R-P were deteriorated, but its strength decreases from 50% at the same manufacturing process to 30%–40% at similar specific surface area. The analysis shows that the large SSA, poor morphology, narrow PSD, and increased internal detects give rise to increase of water requirement. In addition, the deterioration properties are caused by unsuitable temperature of preparation, loose structure, and large average pore diameter in hardened R-P as well.

scholarly journals Structural changes in activated wood-based carbons: correlation between specific surface area and localization of molecular-sized pores

Holzforschung ◽  
2006 ◽  
Vol 60 (1) ◽  
pp. 85-92 ◽  
Author(s):  
Andreas Herzog ◽  
Boris Reznik ◽  
Tengfei Chen ◽  
Thomas Graule ◽  
Ulrich Vogt
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Surface Area ◽  
Adsorption Isotherms ◽  
Structural Changes ◽  
Nitrogen Adsorption ◽  
Average Pore ◽  
High Resolution Tem ◽  
Average Size ◽  
Nitrogen Adsorption Isotherms

Abstract Samples of maple were pyrolyzed and subsequently activated by carbon dioxide at different temperatures for various dwell times. The changes in wood structure were characterized by nitrogen adsorption isotherms, transmission electron microscopy (TEM) with selected-area electron diffraction (SAED), and scanning electron microscopy (SEM). Increasing pyrolysis temperatures promoted increased crystallization of graphitic wood components and mineral-like phases. The average pore diameter derived from nitrogen adsorption isotherms approximately correlated with the results obtained by high-resolution SEM and TEM. The highest surface area was found for samples containing considerable amounts of nanoperforated pit membranes located in intervascular pitting. High-resolution TEM examinations of membrane regions showed foam-like clusters with an average size of 1.7 nm, which are attributed to the selective influence of CO2 activation on pyrolyzed cellulose and lignin.

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