ABSTRACT
Paracetamol is a pharmaceutical analgesic and antipyretic agent. The use of activated carbon is done for the removal of impurities and color by the process of adsorption in the treatment of wastewater generated from paracetamol industries. These industries generate a few 100 metric tons of spent activated carbon (SAC) annually, awaiting either regeneration or disposal. In the present study, the regeneration of SAC samples (Sample 1 and 2) from two pharmaceuticals industries was done by microwave irradiation at low (520 W) and medium (700 W) power. Each sample was exposed to microwave radiations for varied time, i.e., 5, 10, 15, 20, and 30 min. The adsorptive capacity of regenerated activated carbons (AC) was measured by loading them with methylene blue (MB) dye for calculating its methylene blue number (MBN). The MBN values and SEM images of treated samples were compared with that of fresh and SAC. The equilibrium adsorption data were used to calculate maximum monolayer coverage capacity and surface area (SA) of regenerated samples 1 and 2 by Langmuir isotherm. The results obtained show that the SAC can be regenerated successfully by more than 85% when it is subjected to microwave irradiation of 520 W and 700 W. The major advantage of this process is that a significantly high percentage of regeneration can be achieved within a short duration of time.
