Comparison of Surface Areas Calculated from Nitrogen Adsorption and Mercury Porosimetry

2008 ◽  
pp. 130-134 ◽  
Author(s):  
Diane R. Milburn ◽  
Burtron H. Davis
Keyword(s):  
Mercury Porosimetry ◽  
Nitrogen Adsorption ◽  
Surface Areas

scholarly journals Comparison of Mercury Intrusion and Nitrogen Adsorption Measurements for the Characterization of Certain Natural Raw Materials Deposits

2010 ◽  
Vol 7 (1) ◽  
pp. 621-630
Author(s):  
Baghdad Science Journal
Keyword(s):  
Pore Size ◽  
Gas Adsorption ◽  
Raw Materials ◽  
Mercury Porosimetry ◽  
Construction Materials ◽  
Nitrogen Adsorption ◽  
Distribution Data ◽  
Active Components ◽  
Surface Areas ◽  
Wide Range

The porosity of materials is important in many applications, products and processes, such as electrochemical devices (electrodes, separator, active components in batteries), porous thin film, ceramics, soils, construction materials, ..etc. This can be characterized in many different methods, and the most important methods for industrial purposes are the N2 gas adsorption and mercury porosimetry. In the present paper, both of these techniques have been used to characterize some of Iraqi natural raw materials deposits. These are Glass Sand, Standard Sand, Flint Clay and Bentonite. Data from both analyses on the different types of natural raw materials deposits are critically examined and discussed. The results of specific surface areas showed considerable difference between the two sets of data on the same material. This indicates that the material have an external surface which can not be measure by mercury porosimeter. Also pore size distribution data obtained from N2 adsorption measurements shows a wide range of the smallest pore size. This result suggests that materials have micropores using IUPAC definitions of pore size.

Influence of TiO2 on the Pore Structure and Texture of SiO2-PDMS Hybrid Materials

2004 ◽  
Vol 847 ◽  
Author(s):  
Lucía Téllez ◽  
Juan Rubio ◽  
Miguel A. Valenzuela ◽  
Fausto Rubio ◽  
Ernesto Morales ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Pore Structure ◽  
Titanium Oxide ◽  
Hybrid Materials ◽  
Mercury Porosimetry ◽  
Sol Gel ◽  
Nitrogen Adsorption ◽  
The Other ◽  
Surface Areas ◽  
Specific Surface Areas

ABSTRACTPorous SiO2-PDMS-TiO2 hybrid materials have been prepared by the Sol-Gel method using tetraethoxysilane (TEOS), silanol terminated-Polydimethylsiloxane (PDMS) and tetrabuthylortotitanate (TBT) as precursors. These materials were characterized by means of nitrogen adsorption, mercury porosimetry and helium picnometry. It was found that the meso and microporosity are predominant in all samples. The influence of the TBT concentration in the final pore structure and texture of SiO2-PDMS-TiO2 hybrid materials was studied. Results showed that increasing the TBT concentration decreases the pore volume of micropores, mesopores and macropores. On the other hand the specific surface areas of meso and macropores decreases with increasing TBT content, but micropore areas increase with TBT. These results are assigned to the formation of ultramicropores when TBT is added. In addition, surface roughness is found to increase with TBT concentration which is attributed to the formation of hydrous titanium oxide based nanoparticles.

scholarly journals Action Time-Effect and Mechanism of Low-Calcium Fly Ash in Cement-Based Composites

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 681
Author(s):  
Na Yan ◽  
Qingqing Tang ◽  
Ying Zhang ◽  
Guowen Sun
Keyword(s):  
Fly Ash ◽  
Nitrogen Adsorption ◽  
Chemical Effect ◽  
Hydration Products ◽  
X Ray Diffraction ◽  
Degree Of Hydration ◽  
Surface Areas ◽  
Activity Effect ◽  
Low Calcium ◽  
Pore Size Distributions

This study was conducted in order to investigate when low-calcium fly ash plays a physical or chemical effect and what is the chemical effect proportion of low-calcium fly ash. Two types of low-calcium fly ash and quartz powder, with similar fineness as active and inert admixtures, were used as materials in this study. Under different water/binder ratios and hydration ages, the effects of the different types of admixtures and their dosages on the flexural and compressive strength of the composites were studied. X-ray diffraction (XRD), scanning electron microscopy (SEM) and nitrogen adsorption methods, in addition to an assessment of the degree of hydration of the fly ash, were employed to observe the hydration products at different ages, the microstructures of the hydration products, as well as their surface areas and pore size distributions. The results show that during the hydration period of 28 days, the low-calcium fly ash has a micro-aggregate filling physical effect. However, after 56 days, the hydration degree of fly ash begins to exceed 1%. This illustrates that the low-calcium fly ash has both the pozzolanic activity effect and micro-aggregate filling effect. In contrast, the low-calcium fly ash hydrated for 90 days is still dominated by the physical filling effect.

scholarly journals New approach in the application of lignin for the synthesis of hybrid materials

2017 ◽  
Vol 89 (1) ◽  
pp. 161-171 ◽  
Author(s):  
Beata Podkościelna ◽  
Marta Goliszek ◽  
Olena Sevastyanova
Keyword(s):  
Suspension Polymerization ◽  
Nitrogen Adsorption ◽  
Experimental Protocol ◽  
New Approach ◽  
Surface Areas ◽  
Adsorption Data ◽  
Novel Method ◽  
Derivatives Of ◽  
Polymerization Method ◽  
Nitrogen Adsorption Data

AbstractIn this study, a novel method for the synthesis of hybrid, porous microspheres, including divinylbenzene (DVB), triethoxyvinylsilane (TEVS) and methacrylated lignin (L-Met), is presented. The methacrylic derivatives of kraft lignin were obtained by reaction with methacryloyl chloride according to a new experimental protocol. The course of the modification of lignin was confirmed by attenuated total reflectance (ATR-FTIR) and nuclear magnetic resonance (NMR) spectroscopy. The emulsion-suspension polymerization method was employed to obtain copolymers of DVD, TEVS and L-Met in spherical forms. The porous structures and morphologies of the obtained lignin-containing functionalized microspheres were investigated by low-temperature nitrogen adsorption data and scanning electron microscopy (SEM). The microspheres are demonstrated to be mesoporous materials with specific surface areas in the range of 430–520 m2/g. The effects of the lignin component on the porous structure, shape, swelling and thermal properties of the microspheres were evaluated.

Tailoring the Pore Size of Hypercrosslinked Polymer Foams

1996 ◽  
Vol 431 ◽  
Author(s):  
W. P. Steckle ◽  
M. A. Mitchell ◽  
P. G. Apen
Keyword(s):  
Pore Size ◽  
Polyaromatic Hydrocarbons ◽  
Crosslinking Agent ◽  
Nitrogen Adsorption ◽  
Total Surface Area ◽  
Pore Sizes ◽  
Surface Areas ◽  
Small Pore ◽  
High Resolution Tem ◽  
Cure Time

AbstractOrganic analogues to inorganic zeolites would be a significant step forward in engineered porous materials and would provide advantages in range, selectivity, tailorability and processing. Rigid molecular foams or “organic zeolites” would not be crystalline materials and could be tailored over a broader range of pore sizes and volumes. A novel process for preparing hypercrosslinked polymeric foams has been developed via a Friedel-Crafts polycondensation reaction. A series of rigid hypercrosslinked foams have been prepared using simple rigid polyaromatic hydrocarbons including benzene, biphenyl, m-terphenyl, diphenylmethane, and polystyrene, with p-dichloroxylene (DCX) or divinylbenzene (DVB) as the crosslinking agent. Transparent gels are formed suggesting a very small pore size. After drying the foams are robust and rigid. Densities of the resulting foams can range from 0.15g/cc to 0.75g/cc. Nitrogen adsorption studies have shown that by judiciously selecting monomers and crosslinking agent along with the level of crosslinking and the cure time of the resulting gel, the pore size, pore size distribution, and the total surface area of the foam can be tailored. Surface areas range from 160 to 1,200 m2/g with pore sizes ranging from 6Å to 2,000Å. Further evidence of the uniformity of the foams and their pore sizes has been confirmed by high resolution TEM.

scholarly journals ZnTiO3 ceramic nanopowder microstructure changes during compaction

2013 ◽  
Vol 45 (2) ◽  
pp. 209-221
Author(s):  
N. Labus ◽  
J. Krstic ◽  
S. Markovic ◽  
D. Vasiljevic-Radovic ◽  
M.V. Nikolic ◽  
...  
Keyword(s):  
Particle Size ◽  
Pore Size ◽  
Size Distribution ◽  
Mercury Porosimetry ◽  
Critical Diameter ◽  
Nitrogen Adsorption ◽  
Powder Particle Size ◽  
Scanning Electron Micrographs ◽  
Force Microscopy ◽  
Scanning Electron

ZnTiO3 nanopowder as a constitutive component in compact production was primarily characterized. Scanning electron micrographs of as received powder were recorded. Mercury porosimetry and nitrogen adsorption were also performed on loose powder. Particle size distribution in a water powder suspension was determined with a laser particle size analyser. Compaction was performed on different pressures in a range from 100 to 400 MPa using the uniaxial double sided compaction technique without binder and lubricant. Micrographs of compacted specimens were obtained using scanning electron microscopy and atomic force microscopy. Pore size distribution was also determined by mercury porosimetry and nitrogen adsorption. Results revealed that with increasing pressure during compaction interagglomerate pores diminish in size until they reach some critical diameter related to the intra-agglomerate pore size.

Structural and surface aspects of thermally treated copper aluminium mixed hydroxides

1991 ◽  
Vol 69 (10) ◽  
pp. 1511-1515 ◽  
Author(s):  
Awad I. Ahmed ◽  
S. E. Samra ◽  
S. A. El-Hakam
Keyword(s):  
Pore Structure ◽  
Copper Content ◽  
Textural Properties ◽  
Nitrogen Adsorption ◽  
Phase Changes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Areas ◽  
Structure Surface ◽  
Adsorption Desorption

CuO–Al2O3 catalysts containing various amounts of copper oxide have been prepared by precipitation. The phase changes were studied by X-ray diffraction. The results obtained revealed that the thermal treatment of solid CuO–Al2O3 at 700 °C produced only crystalline CuO. Heating to 900 °C led to the formation of copper alumina spinel together with unreacted CuO and γ-Al2O3. The spinel content was found to increase with increasing copper content. Nitrogen adsorption–desorption isotherms on the calcined samples have been measured. Surface areas have been calculated and the pore structure analysed. The textural properties of the system were found to depend on both the copper content and the calcination temperature. Key words: CuO, Al2O3 catalysts, structure, surface area, pore structure.

scholarly journals Catalytic Decomposition of H2O2 over Pure and Li2O-Doped Co3O4 Solids

1998 ◽  
Vol 16 (9) ◽  
pp. 733-746 ◽  
Author(s):  
Gamil A. El-Shobaky ◽  
Nagi R.E. Radwan ◽  
Farouk M. Radwan
Keyword(s):  
Heat Treatment ◽  
Specific Surface ◽  
Catalytic Decomposition ◽  
Nitrogen Adsorption ◽  
Progressive Increase ◽  
Lithium Oxide ◽  
Lithium Nitrate ◽  
Surface Areas ◽  
Catalytically Active ◽  
Cobaltic Oxide

Pure and doped Co3O4 samples were prepared by the thermal decomposition at 500–900°C of pure and lithium nitrate-treated basic cobalt carbonate. The amounts of dopant added were varied in the range 0.75–6 mol% Li2O. The effects of this treatment on the surface and catalytic properties of cobaltic oxide solid were investigated using nitrogen adsorption at −196°C and studies of the decomposition of H2O2 at 30–50°C. The results obtained revealed that Li2O doping of Co3O4 followed by heat treatment at 500°C and 600°C resulted in a progressive increase in the value of the specific surface area, SBET, to an extent proportional to the amount of dopant present. However, the increase was more pronounced in the case of solid samples calcined at 500°C. This increase in the specific surface areas has been attributed to the fixation of a portion of the dopant ions on the uppermost surface layers of the solid leading to outward growth of the surface lattice. The observed increase in SBET due to Li2O doping at 500°C might also result from a narrowing of the pores in the treated solid as a result of the doping process. Lithium oxide doping of cobaltic oxide followed by heat treatment at 700–900°C resulted in a significant decrease in the SBET, Vp and r̄ values. Pure and doped solids precalcined at 500°C and 600°C exhibited extremely high catalytic activities which were not much affected by doping with Li2O. On the other hand, doping followed by calcination at 700–900°C brought about a considerable and progressive increase in the catalytic activity of the treated solids. This treatment did not modify the activation energy of the catalysed reaction, i.e. doping of Co3O4 solid followed by heating at 700°C and 900°C did not alter the mechanism of the catalytic reaction but increased the concentration of catalytically active constituents taking part in the catalytic process without altering their energetic nature.

scholarly journals A Study of the Micropore Structure of Carbonized Rayon Yarn by Nitrogen Adsorption and Nonane Pre-Adsorption

1985 ◽  
Vol 2 (2) ◽  
pp. 89-95 ◽  
Author(s):  
J. N. Bohra ◽  
K. S. W. Sing
Keyword(s):  
External Surface ◽  
Nitrogen Adsorption ◽  
The Other ◽  
Adsorption Method ◽  
Micropore Structure ◽  
Surface Areas ◽  
Three Samples ◽  
Two Samples ◽  
Before And After ◽  
Gain Access

Adsorption isotherms of nitrogen have been determined at 77 K on three samples of carbonized rayon yarn, both before and after the pre-adsorption of n-nonane. In their original state the three samples were all highly microporous. Application of the αs-method of isotherm analysis reveals that their micropore volumes were 0·17–0·19 cm3g−1 and their external surface areas 20–27 m2g−1 (the corresponding BET areas being 427–483 m2g−1). Nonane pre-adsorption resulted in blockage of the entire micropore structure only in the case of one sample: micropore volumes ∼0·1 cm3g−1 were still available for nitrogen adsorption in the other two samples. It appears that nitrogen molecules were able to gain access to some parts of these micropore structures through wider pore entrances which were not completely blocked by the pre-adsorbed nonane. The work has shown that the nonane pre-adsorption method requires further investigation before it can be used with confidence for the assessment of microporosity.

Active Magnesia. III. X-ray versus Nitrogen Adsorption Surface Areas.

1947 ◽  
Vol 51 (3) ◽  
pp. 763-767 ◽  
Author(s):  
A. C. Zettlemoyer ◽  
W. C. Walker
Keyword(s):  
Nitrogen Adsorption ◽  
X Ray ◽  
Surface Areas ◽  
Adsorption Surface
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