抄録
Most of pulp and paper industry, especially in Thailand use numerous eucalyptus woods and generate pulp wastes. These wastes were generally used as fuel in the plant. Its residues were eliminated by landfills. This work synthesized the activated carbon from the abundant fragments of eucalyptus woods in pulp and paper industry by chemical activation and studied a value added use of pulp wastes as the adsorbent. The effects of the carbonization temperature of the eucalyptus woods from 300 to 700 °C and time from 30 to 90 mins were studied by controlling the nitrogen flow rate at 100 ml/min with the heating rate of 10°C/min. The results showed that carbonization at 500°C for 45 mins was the appropriate condition for activated carbon precursor. In chemical activation the weight ratio of chars/40- wt% NaOH solution of 1.25 were used at the temperature ranges of 500 to 700°C for 60 to 120 mins. The iodine and methylene blue adsorption capacities were measured. The iodine number of the activated carbon chemically activated at 500°C for 120 mins (AC(500,120)) and that of pulp wastes were 709 and 670 mg/g, respectively. The adsorption of methylene blue solution of AC (500,120) and that of pulp wastes were 196 and 112 mg/g, respectively. The adsorption isotherm of AC (500,120) was type I whereas that of pulp wastes was BET model. The results from the Scanning Electron Micrographs showed that the structure of AC (500,120) was porous and the structure of pulp wastes was partially porous. The results confirmed that pulp wastes can be used as the adsorbent.
