Production, Activation and CO₂ Uptake Capacity of a Carbonaceous Microporous Material from Palm Oil Residues

Abstract

While Malaysia produces about half of the world’s palm oil and is the largest producer and exporter worldwide, oil palm industries generate large amounts of lignocellulosic biomass waste as a sub-product with no economic market value other than feedstock for energy valorisation. With the aim to increase the sustainability of the sector, in this work we prepare new materials for CO2 capture from palm oil residues (empty fruit bunches and kernels). The biochar is obtained through the carbonisation of the residues and is physically and chemically activated to produce porous materials. The resulting microporous samples have similar properties to other commercial activated carbons, with BET surfaces in the 320–880 m2/g range and pore volumes of 0.1–0.3 cm3·g−1. The CO2 uptake at room temperature for physically activated biochar (AC) was 2.4–3.6 mmolCO2/gAC, whereas the average CO2 uptake for chemically activated biochar was 3.36–3.80 mmolCO2/gAC. The amount of CO2 adsorbed decreased at the highest temperature, as expected due to the exothermic nature of adsorption. These findings confirm the high potential of palm oil tree residues as sustainable materials for CO2 capture.

Keywords

• palm oil waste
• CO₂ uptake
• adsorption
• chemical and physical activation
• biochar