Optimization of manufacturing conditions for activated carbon from Turkish lignite by chemical activation using response surface methodology

The purpose of this research is to obtain optimal processing conditions for activated carbon from lignite by chemical activation with K2CO3 using response surface methodology (RSM). The activated carbons produced were characterized by carbon yield (%), BET surface area, porosity development (total pore volume and micropore fraction). RSM based on a five-variable central composite rotatable design was used to determine the effect of chemical ratio (ranging from 0 to 4) and activation temperature (ranging from 500 °C to 900 °C) on the responses levels. Each response has been described by a second order model that was found to be appropriate to predict most of the responses in every experimental region. The most influential factor on each experimental design response have been identified from the analysis of variance (ANOVA). The optimum conditions for manufacturing of activated carbon from Turkish lignite, which were based on response surface and contour plots, were found as follows: chemical ratio of 2.05 and carbonization temperature of 800 °C.