Mesoporous activated carbon yielded from pre-leached cassava peels.

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Activated carbon (AC) is crucial but often derived from fossil fuels.
• Agricultural waste, like cassava peels, presents a sustainable alternative precursor.
• Optimizing AC properties requires controlled processing conditions.

Purpose of the Study:

• To develop an eco-friendly process for producing high-surface-area activated carbon from cassava peels.
• To investigate the effect of pre-leaching and high-temperature activation on AC properties.
• To characterize the resulting activated carbon for potential applications.

Main Methods:

• Cassava peels were pre-leached with sodium hydroxide (NaOH).
• Activation was performed using potassium hydroxide (KOH) at a 5:2 ratio (KOH:peel).
• Carbonization occurred in a stepwise process between 480°C and 780°C.

Main Results:

• A maximum yield of 42% activated carbon was achieved.
• The highest BET surface area reported for cassava peel AC (1684 m²g⁻¹) was obtained.
• At 780°C, a significant increase in mesopore volume (0.471 cm³g⁻¹) was observed, yielding mesoporous AC.

Conclusions:

• Pre-leaching with NaOH and high-temperature KOH activation (above potassium's melting point) are key to producing highly porous AC from cassava peels.
• The optimized process yields activated carbon with exceptional surface area and pore characteristics.
• This method offers a sustainable route to high-performance activated carbon from agricultural waste.