Characteristics of activated carbon from sludge and peanut shell and its application for phenol adsorption

Abstract

In this study, activated carbon (AC) was prepared from municipal sludge with peanut shell as the carbon additive and the ferric chloride as activator. Then the properties of AC activated by ferric chloride (FAC) and non-activated (NAC) were analyzed. Main results show that FAC has extremely higher BET surface area (781.5 m2/g) and pore volume (0.859 m3/g) than NAC, which implies that ferric chloride can effectively promote the formation of developed pore structures of AC. Moreover, the obtained ACs were used as adsorbent to remove phenol in aqueous solution. Results indicate that FAC and NAC have a higher adsorption capacity in the range pH of 7–9 and 1 g/L is the most suitable dosage of AC, considering of the removal rate and adsorption capacity. The adsorption kinetic data and adsorption isotherm data are well described by the pseudo-second order model and Freundlich isotherm model. The maximum equilibrium adsorption capacity is 109.58 mg/g (1 g/L, pH 8.0, 298K). In summary, it is an effective method to prepare AC from sludge and a small amount of peanut shell by using ferric chloride as activator and to remove phenol. This provides a potential option for sludge resource recovery.