Abstract:
Jackfruit is a plant that can thrive in tropical climates. Generally the part of the jackfruit
plant that is often used is the fruit, while the seeds of the jackfruit are often wasted.
Several studies have tried to find solutions to utilize ripe jackfruit seeds that have not
been utilized optimally, one of which is used as an adsorbent. The purpose of this study
is to analyze the variation of dose and optimum contact time on the adsorption of indigo
carmine dye by HNO3 activated jackfruit seed powder and charcoal. Spechtrofotometer
used to analyze the indigo carmine before and after adsorption. The adsorbent
functional groups were characterized using FTIR and the surface morphology was
characterized using SEM. The results of this research showed that the optimum
conditions for adsorption of HNO3 activated jackfruit seed powder and activated carbon
on Indigo Carmine dye occurred at a dose of 0.4 g and a contact time of 120 minutes
with efficiency values of 75.57% and 71.06%. Based on the results of the FTIR test, it
was found that the jackfruit seed powder contained –OH, N-H, C-H and C=O groups,
while the jackfruit seed charcoal did not contain –OH. Based on the results of the SEM
test, it was found that the powder and charcoal of jackfruit seeds after activation had
more open pores than powder and charcoal before activation. After adsorption, the pores
were covered by indigo carmine dye which indicated that the adsorption was working
optimally. The result showed that HNO3 activated jackfruit seed powder is more
effective at absorbing indigo carmine dye than jackfruit seed charcoal.