Characterization and Adsorption Isotherm Measurement of Phenol On Activated Carbon

The research on adsorption isotherm measurement of phenol on activated carbon has
been conducted prior to the increase in demand by the industry regarding the suitable
method of removing this organic compound. Phenol is one of the components in
industrial wastewaters which can bring detrimental effect to human life. Due to the
increase in industrial wastewaters, the demand for removal of organic compounds
including phenol has been increased. There are various separation method recognized
such as coagulation, filtration, oxidation, aeration, ion exchange and activated carbon
treatment. However, the latter method has been proven to be more efficient in
removing these compounds, thus is adopted in this study.
The objectives ofthis research are to determine the adsorption isotherm measurement
of phenol on various types of activated carbon at wide range of temperatures, to
determine the most suitable adsorbent for this type of application and to characterize
the physical properties of the adsorbents used in terms of their surface area, average
pore diameter and microporous distribution. There are four types of activated
carbons that have been selected which are 2.5 and 1.5 mm diameter of Granular
Activated Carbon and GR and Powder Extra Pure of Powdered Activated Carbon.
The scope of study is limited to three different temperatures.
The surface area, average pore diameter and microporous distribution are analyzed
using the QUANTACHROME AUTOSORBanalyzer whereas the amount ofphenol
removed by the activated carbons is determined from the adsorption isotherm
measurement which shows that the amount of phenol adsorbed varies with the
equilibrium phenol concentration. The analysis of concentration of phenol is done
using UV-VIS Spectrophotometer.
From the result of adsorption isotherm measurement, 2.5 mm diameter of Granular
Activated Carbon is the best option in removing phenol and the adsorption is proven
to be favored at lower temperature. Since the diameter of phenol is less than the
diameter of micropores, the adsorption capacity of phenol is very much affected by the volume of microporous structure. This finding is supported by the results onthe
characterization of adsorbents which shows that 2.5 mm diameter Granular Activated
Carbon has the highest micropore volume and area. Thus, it can be concluded that
removal of adsorbate which has diameter less than the diameter of micropore
increases with the increase in volume of micropores and is favored at lower possible
temperature.