Chemistry and chemical technology
63
MATERIAL AND METHODS.
1.
The activated carbon production process takes place in two stages, if you do not take
into account such stages as drying and crushing (classification):
2.
Pyrolysis of the feedstock at a temperature of 400 - 600 °C. As a result, carbonization is
obtained, which is well known to us as charcoal for barbecues.
3. High temperature treatment of 800 - 1000 °C carbonization using water vapor or various
mixtures of liquids. The result is activated carbon – one of the best adsorbents.
The pellets were de-volatilized in a single-zone activation furnace at a temperature
determined using C for all samples), in an atmosphere of thermo gravimetric analysis (800
carbon dioxide, the consumption of which was 200 l/h.The refined de-volatilization parameters
for each sample are presented. Activation of granules. The activation of the granules was carried
out in an activation furnace at a temperature determined on the basis of thermo gravimetric
0
C for
all samples, in an atmosphere of water vapor analysis and equal to 900 (steam consumption was
600 l/h at all activation stages) to the degree of burnout of 45-50%.
The sorption properties of activated carbons largely depend on the nature of their porous
structure. Therefore, specific surface area and porosity are extremely important characteristics of
sorbents, and much attention is paid to their study
.
The porosity of the obtained AG-3 samples was determined using the NOVA-1200e
automatic high-speed porous structure analyzer. The results of the analysis of the porous
structure of the obtained granules are given.
By the nature of the porous structure, all the obtained coals are microporous, but their
micropore sizes are large (from 0.677 to 0.839 nm), which is indicated by a small value of the
characteristic adsorption energy (from 15.488 to 19.199 kJ/mol). The volume of mesopores is
very small (from 0.0324 to 0.0894 cm
3
/g).
AG-3 grade activated carbon is universal for adsorption of various organic compounds from
liquid and gas media. The mechanical strength of coal allows the use of large-volume structures,
thereby ensuring a long service life.Activated carbon of this brand can be subjected to thermal
regeneration with a high degree of restoration of the original properties with a small loss of mass.
Appearance cylindrical granules of dark gray and black color with a size of 1.5-2.8 mm.
Activated carbon AG-3 contains a huge amount of mesopores (from 2 to 50 nm), therefore it is
suitable for adsorption of larger organic molecules. Ithas a highsorptioncapacity.
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