Development of properties within particles of active carbons obtained by a steam activation process

Langmuir ◽  
1993 ◽  
Vol 9 (10) ◽  
pp. 2509-2512 ◽  
Author(s):  
Bronislaw Buczek
Keyword(s):  
Activation Process ◽  
Active Carbons ◽  
Steam Activation

scholarly journals Preparation and characterization of activated carbon from bio-diesel by-products (Jatropha seedcake) by steam activation

2012 ◽  
Vol 47 (3) ◽  
pp. 257-264
Author(s):  
MS Islam ◽  
MA Rouf ◽  
S Fujimoto ◽  
T Minowa
Keyword(s):  
Activated Carbon ◽  
Structural Changes ◽  
Pyrolysis Temperature ◽  
Hold Time ◽  
Raw Material ◽  
Bet Surface Area ◽  
Activation Process ◽  
Steam Activation ◽  
Activation Temperature ◽  
Ft Ir

Activated carbon was prepared using bio-diesel waste (Jatropha seedcake) by conventional carbonization followed by steam activation process on a laboratory scale. Preliminary tests were conducted to investigate the influences of different operating parameters, such as initial material size, pyrolysis temperature and hold time on the properties of pyrolized chars. To determine the optimum conditions for producing activated carbon, the effect of activation temperature and activation time have been studied. The maximum BET surface area of 613.43 m2/g and highest methylene blue adsorption capacity of 8.27 mg/g was obtained at a pyrolysis temperature of 600°C for hold time 1.5 hr followed by steam activation at a temperature of 800°C for a hold time of 1 hr. The produced activated carbon was almost like ash at 900°C. FT-IR and TG/DTA have been done in order to understand the structural changes during the process. The waste material was a suitable raw material for the production of good quality activated carbon. DOI: http://dx.doi.org/10.3329/bjsir.v47i3.13056 Bangladesh J. Sci. Ind. Res. 47(3), 257-264, 2012

Preparation of activated carbon from needle coke via two-stage steam activation process

2019 ◽  
Vol 237 ◽  
pp. 22-25 ◽  
Author(s):  
Ui-Su Im ◽  
Jiyoung Kim ◽  
Seon Ho Lee ◽  
Song mi Lee ◽  
Byung-Rok Lee ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Activation Process ◽  
Needle Coke ◽  
Steam Activation ◽  
Two Stage

AN ISOPIESTIC INVESTIGATION OF CHARCOAL ACTIVATION

1949 ◽  
Vol 27b (2) ◽  
pp. 101-115
Author(s):  
S. Barnartt ◽  
J. B. Ferguson
Keyword(s):  
Capillary Condensation ◽  
Relative Rate ◽  
Saturation Pressure ◽  
Isopiestic Method ◽  
Activation Process ◽  
Steam Activation ◽  
Sorption Data ◽  
Straight Lines ◽  
Low Pressures ◽  
Chemically Selective

The isopiestic method was used to study the sorption of carbon tetrachloride, water, methanol, and toluene by a series of charcoals representing the same coconut shell source at different stages of steam activation. The sorption of water by two charcoals of this series impregnated with benzoic acid was similarly investigated. The isopiestic charges of this activation series of charcoals were linearly related over wider pressure ranges than were those of unrelated charcoals. The activation process was found to be connected primarily with the principal pressure range over which single straight lines were obtained on plotting the isopiestic charges one against the other. The isopiestic data presented the following picture of charcoal activation. The activation process has created surfaces, probably of a heterogeneous character, which are active to all the four vapors studied. At any stage of activation these surfaces take up proportionate quantities, but not equal liquid volumes, of each sorbate at saturation pressure. The various types of surfaces increase in abundance with activation at the same relative rate, so that they are always present in the charcoal in the same relative proportions, up to a certain stage of activation. At this stage the production of the surfaces active at relatively low pressures begins to decline. This indicates that new pores are being created more slowly in comparison with the widening of existing pores. In addition to the active surfaces just described, the activation process produces some chemically selective centers which are active at minute relative pressures. The water sorption data discredit the theory of capillary condensation.

scholarly journals Preparation of active carbons from olive wood

1985 ◽  
Vol 2 (4) ◽  
pp. 263-269 ◽  
Author(s):  
J. De D. LÓPez-Gonzlez ◽  
C. Valenzuela-Calahorro ◽  
A. Navarrette-Guijosa ◽  
V. Gomez-Serrano
Keyword(s):  
Carbon Dioxide ◽  
Heating Rate ◽  
Surface Area ◽  
Mercury Porosimetry ◽  
Starting Material ◽  
Activation Process ◽  
Active Carbons ◽  
Activation Time ◽  
Adsorption Of Nitrogen

Active carbons were prepared by activating carbonized products (obtained by pyrolysis of olive wood in nitrogen at 1073 K) and olive wood itself under a flow of carbon dioxide at 1048 K. The effect on the development of surface area and porosity of such variables as activation time, heating rate, previous carbonization time, and starting material (either carbonized samples or wood) were followed by adsorption of nitrogen at 77 K. Changes of meso- and macroporosity during the activation process were monitored by mercury porosimetry. Surface area (BET values) varies from 469 up to 854 m2.g–1. A development of micro, meso and macroporosity takes place depending on activation time.

scholarly journals Activated Carbon Preparation from Eucalyptus Wood Chips using Continuous Carbonization - Steam Activation Process in a Batch Intermittent Rotary Kiln

2020 ◽  
Author(s):  
Sumrit Mopoung ◽  
Nuchjira Dejang
Keyword(s):  
Activated Carbon ◽  
Rotary Kiln ◽  
Carbon Materials ◽  
Activated Carbons ◽  
Wood Chips ◽  
Bet Surface Area ◽  
Activation Process ◽  
Steam Activation ◽  
Activation Temperature ◽  
Eucalyptus Wood

Abstract The production of activated carbon from eucalyptus wood chips by steam activation in a 2000 kg batch intermittent rotary kiln with continuous carbonization - steam activation process at 500°C to 700 °C was studied. The activated carbon products were characterized by FTIR, SEM-EDS, Raman spectroscopy, and BET analyzer. Percent yields, iodine number, and methylene number of the produced activated carbon materials were also measured. It was shown that the percent yield of the activated carbon materials made in the temperatures range of 500°C to 700 °C are 21.63 ± 1.52% − 31.79 ± 0.70% with capacities of 518–737 mg I2/g and 70.11–96.93 mg methylene blue /g. The BET surface area and micropore volume of the activated carbons are 426.8125-870.4732 m2/g and 0.102390–0.215473 cm3/g, respectively. The steam used in the process could create various oxygen containing surface functional groups such as –CO and –COC groups. In addition, it could also increase the amorphous nature of the activated carbon product. These properties of the activated carbon products are increased with increasing steam activation temperature from 500°C to 700°C. As a result, the activated carbon materials produced at activation temperatures of 600 °C and 700 °C have higher adsorption

scholarly journals Activated carbon preparation from eucalyptus wood chips using continuous carbonization–steam activation process in a batch intermittent rotary kiln

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sumrit Mopoung ◽  
Nuchjira Dejang
Keyword(s):  
Methylene Blue ◽  
Activated Carbon ◽  
Rotary Kiln ◽  
Carbon Materials ◽  
Wood Chips ◽  
Bet Surface Area ◽  
Activation Process ◽  
Steam Activation ◽  
Eucalyptus Wood ◽  
Bet Analysis

AbstractThe production of activated carbon from eucalyptus wood chips by steam activation in a 2000 kg batch intermittent rotary kiln with continuous carbonization–steam activation process conducted at 500 °C to 700 °C was studied. The activated carbon products were characterized by FTIR, SEM–EDS, Raman spectroscopy, and BET analysis. Percent yields, iodine number, and methylene blue number of the produced activated carbon materials were measured as well. It was shown that the percent yields of the activated carbon materials made in the temperature range from 500 to 700 °C are 21.63 ± 1.52%–31.79 ± 0.70% with capacities of 518–737 mg I2/g and 70.11–96.93 mg methylene blue/g. The BET surface area and micropore volume of the activated carbons are 426.8125–870.4732 m2/g and 0.102390–0.215473 cm3/g, respectively. The steam used in the process could create various oxygen containing surface functional groups such as –CO and –COC groups. In addition, it could also increase the amorphous nature of the activated carbon product. These properties of the activated carbon products are increased with increasing steam activation temperature from 500 to 700 °C. As a result, the activated carbon materials produced at activation temperatures of 600 °C and 700 °C exhibit higher adsorption.

SEM and Auger microanalysis studies of Cu-Be dynode surfaces at each activation condition

1978 ◽  
Vol 36 (1) ◽  
pp. 524-525
Author(s):  
T. Koshikawa ◽  
Y. Fujii ◽  
E. Sugata ◽  
F. Kanematsu
Keyword(s):  
Electron Emission ◽  
Secondary Electron ◽  
Secondary Electron Emission ◽  
Life Time ◽  
Activation Process ◽  
Beam Diameter ◽  
Activation Temperature ◽  
Electron Multiplier ◽  
Activation Condition ◽  
Activation Conditions

The Cu-Be alloys are widely used as the electron multiplier dynodes after the adequate activation process. But the structures and compositions of the elements on the activated surfaces were not studied clearly. The Cu-Be alloys are heated in the oxygen atmosphere in the usual activation techniques. The activation conditions, e.g. temperature and O2 pressure, affect strongly the secondary electron yield and life time of dynodes.In the present paper, the activated Cu-Be dynode surfaces at each condition are investigated with Scanning Auger Microanalyzer (SAM) (primary beam diameter: 3μmϕ) and SEM. The commercial Cu-Be(2%) alloys were polished with Cr2O3 powder, rinsed in the distilled water and set in the vacuum furnance.Two typical activation condition, i.e. activation temperature 730°C and 810°C in 5x10-3 Torr O2 pressure were chosen since the formation mechanism of the BeO film on the Cu-Be alloys was guessed to be very different at each temperature from the results of the secondary electron emission measurements.

The Binding of Calcium Ions to Bovine Factor X by Rate Dialysis

1978 ◽  
Vol 40 (02) ◽  
pp. 350-357
Author(s):  
Robert H Yue ◽  
Menard M Gertler
Keyword(s):  
Molecular Weight ◽  
Dissociation Constant ◽  
Calcium Ions ◽  
Activation Process ◽  
Factor X ◽  
The Real ◽  
High Affinity ◽  
Binding Data ◽  
Sequential Mechanism ◽  
Bovine Factor

SummaryThe binding of Ca+2 to bovine factor X (molecular weight of 74,000) (Yue und Gertler 1977) was studied by the technique of rate dialysis and with the use of 45Ca+2. The binding data are consistent with a model of sequential mechanism. One mole of Ca+2 binds to the glycoprotein with a dissociation constant of 5.2 × 10-5 M and an additional 39 ± 4 moles of Ca+2 bind to this zymogen with a dissociation constant of 3.7 × 10-3M. The binding of the high affinity Ca+2 causes a functionally significant change in the zymogen, and (calcium) (factor X) complex is the real substrate in the activation process by the protease in Russell’s viper venom.

scholarly journals Computer Analysis of the Effect of Activation Temperature on the Microporous Structure Development of Activated Carbon Derived from Common Polypody

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2951
Author(s):  
Mirosław Kwiatkowski ◽  
Jarosław Serafin ◽  
Andy M. Booth ◽  
Beata Michalkiewicz
Keyword(s):  
Activated Carbon ◽  
Porous Structure ◽  
Computer Analysis ◽  
Density Functional ◽  
Activated Carbons ◽  
Chemical Activation ◽  
Geometrical Parameters ◽  
Activation Process ◽  
Microporous Structure ◽  
Activation Temperature

This paper presents the results of a computer analysis of the effect of activation process temperature on the development of the microporous structure of activated carbon derived from the leaves of common polypody (Polypodium vulgare) via chemical activation with phosphoric acid (H3PO4) at activation temperatures of 700, 800, and 900 °C. An unconventional approach to porous structure analysis, using the new numerical clustering-based adsorption analysis (LBET) method together with the implemented unique gas state equation, was used in this study. The LBET method is based on unique mathematical models that take into account, in addition to surface heterogeneity, the possibility of molecule clusters branching and the geometric and energy limitations of adsorbate cluster formation. It enabled us to determine a set of parameters comprehensively and reliably describing the porous structure of carbon material on the basis of the determined adsorption isotherm. Porous structure analyses using the LBET method were based on nitrogen (N2), carbon dioxide (CO2), and methane (CH4) adsorption isotherms determined for individual activated carbon. The analyses carried out showed the highest CO2 adsorption capacity for activated carbon obtained was at an activation temperature of 900 °C, a value only slightly higher than that obtained for activated carbon prepared at 700 °C, but the values of geometrical parameters determined for these activated carbons showed significant differences. The results of the analyses obtained with the LBET method were also compared with the results of iodine number analysis and the results obtained with the Brunauer–Emmett–Teller (BET), Dubinin–Radushkevich (DR), and quenched solid density functional theory (QSDFT) methods, demonstrating their complementarity.

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