Abstract:
Pineapple leaf were potentially used as an alternative source of adsorbent because of high
cellulose content. This research aims to determine the characteristics of pineapple leaf carbon
activated using microwave irradiation and determine the adsorption capacity of activated
pineapple leaf carbon in adsorbing methyl orange dye. Pineapple leaf carbon was made through a
carbonization process for 2 hours at 400°C. Pineapple leaf carbon was delignified using NaOH
9% to separated lignin and cellulose. Pineapple leaf carbon before and after activation used
microwave irradiation (500, 600, and 700 W) was characterized based on SNI No.06-3730-1995
quality standards which included water content, ash content, iodine adsorption capacity, and
methylene blue adsorption capacity. The activated carbon adsorbent from pineapple leaf was
contacted with methyl orange dye at a concentration of 50 ppm for 15 minutes with variations in
adsorbent mass (0.05; 0.10; 0.15; 0.20; and 0.25 g). Function group of adsorben was analysed
using FTIR, surface morphology and element content was analysed using SEM-EDS. The
research results showed that the optimum microwave irradiation power to activate pineapple leaf
carbon was 600 W for 6 minutes with a water content value of 4.463%; ash content of 5.23%;
iodine adsorption capacity of 482.22 mg/g; and the adsorption capacity of methylene blue was
18.0323 mg/g. The best efficiency adsorption of methyl orange dye was 58.8233% on a mass of
0,20 g. The FTIR result was functional groups found in pineapple leaf carbon before and after
activation were O-H stretching, C-H stretching, C=C aromatic, C=O carbonyl, and C-H
aromatic. The result of SEM-EDS was surface of pineapple leaf carbon before activation had a
less hollow structure and still contains many impurities compared to the surface of carbon after
activation using microwave irradiation. Based on this research, it could be concluded that the
microwave activation process was not good in improving the quality of carbon in adsorbing dyes
due to the destructive effect of pineapple leaf carbon.
