a b s t r a c t
The purpose of this work is to obtain optimal preparation conditions for activated carbons prepared
from rattan sawdust (RSAC) for removal of disperse dye from aqueous solution. The RSAC was prepared
by chemical activation with phosphoric acid using response surface methodology (RSM). RSM based on
a three-variable central composite design was used to determine the effect of activation temperature
(400–600 ◦C), activation time (1–3 h) and H3PO4:precursor (wt%) impregnation ratio (3:1–6:1) on C.I.
Disperse Orange 30 (DO30) percentage removal and activated carbon yield were investigated. Based on
the central composite design, quadratic model was developed to correlate the preparation variables to
the two responses. The most influential factor on each experimental design responseswas identified from
the analysis of variance (ANOVA). The optimum conditions for preparation of RSAC, whichwere based on
response surface and contour plots, were found as follows: temperature of 470 ◦C, activation time of 2 h
and 14 min and chemical impregnation ratio of 4.45.