One of methods to overcome lead pollution in water is adsorption process.
Rice hull, an abundance agriculture side product in Indonesia, would turn to ash and use
as an alternative adsorbent for lead adsorption. The objectives of this research were to
explore how much lead could be adsorbed on rice hull ash and to determine a suitable
adsorption isotherm model for this process. The batch sorption experiments were carried
out in the 1 liters stirred glass vessel containing 5 ppm Pb(NO
3
)
2
solution. The weights of
adsorbent (rice hull ash) introduced into the vessel were 1 g, 5 g, 8 g and 15 g. The
temperatures of solution were 35
o
C, 45
o
C and 55
o
C. After reaching equilibrium the
solution was analyzed for the remaining Pb
2+
by AAS. The results showed that the
increase in temperature was followed by the increase in amount of Pb
2+
adsorbed. The
maximum sorption was at 55
o
C where 74.5% of initial Pb
2+
was adsorbed or it was
0.12412 mg/g adsorbent. It was also found that the Freundlich isotherm model was
superior to the others.
Keywords: adsorption, lead pollution, rice hull ash, isotherm adsorption mode
