High pressure methane adsorption on microporous carbon monoliths prepared by olives stones

• A series of activated carbon pellets without binder were prepared by chemical activation of olive stones with H3PO4.
• The activation temperature varied from 350 to 1000 °C.
• Methane storage isotherm at 30 °C and up to 25 bar was measured for the investigated materials.
• N2 adsorption at 77 K does not adequately describe CH4 adsorption capacity.
• CH4 adsorption capacity not only depends on the micropore volume but also strongly depends on the micropore size distribution.

The purpose of this work was to prepare various active carbons from the same precursor at various activation temperatures, and investigate both porosity development and corresponding methane storage capacities. A series of activated carbon pellets without binder have been prepared by chemical activation of olive stones with H3PO4. The activation temperature varied from 350 to 1000 °C. All carbons have been characterized by adsorption of N2 (−196 °C) and SEM. The carbon materials exhibited predominant microporosity, and specific surface area increased from 532 to 1014 m2 g−1. Methane storage isotherm at 30 °C and up to 25 bar was measured for the investigated materials. The methane uptake correlated to the micropore volume and specific surface area, provided by the adsorption of N2 at −196 °C.

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