CHANGES OF SURFACE CHARACTERISTICS
 AND PORE SIZE DISTRIBUTION OF PETROLEUM COKE
 DURING ITS CALCINATION IN THE PRESENCE OF POTASSIUM HYDROXIDE

Abstract

Change of surface properties and pore distribution in petroleum coke at carbonization stage at 900 °C in presence
 of potassium hydroxide has been studied. CO2 adsorption and desorption isotherms at 298 K have been obtained
 for samples of raw and carbonized petroleum coke without and with potassium hydroxide addition. For pore shape and
 size distribution analysis GCMC (Grand Canonical Monte Carlo) computer simulation method has been used. Regularity
 of changes in volume, specific surface area and distribution of cylindrical and slit-shaped pores depending on the
 amount of potassium hydroxide added prior to carbonization stage in petroleum coke has been revealed. Extreme dependence
 of change in specific surface area and pore volume on potassium hydroxide content in carbonized coke has
 been identified. It has been found that addition of potassium hydroxide of less than 50% wt. reduces pore quantity and
 specific surface area of carbonized coke. The main contribution to the coke specific surface area is made by slit-shaped
 and cylindrical mesopores, as well as cylindrical macropores. It has been shown that by varying the amount of potassium
 hydroxide added to petroleum coke prior to its carbonization it is possible to regulate the formed pores distribution
 in terms of shape and size.