Conversion of some fruit stones and shells into activated carbons

Abstract EN

The pyrolysis of certain biomass waste (stones of date, apricot, peach, and olive as well as shells of walnut and coconut) was investigated to prepare activated carbons (ACs) suitable for some commercial purposes.

The pyrolysis process was performed into a fixed bed reactor which was designed for this purpose.

The resulted char was chemically activated using NaOH and the adsorption characteristics, such as iodine number, methylene blue (MB) value, and p-nitrophenol (PNP) value were measured.

The surface area of the prepared ACs was estimated from the calibration curve as between IN and BET surface area of some established ACs from the literature.

The adsorption from solution method was also used to measure the specific surface area of the prepared ACs, using MB and PNP as solutes.

The adsorption isotherms of the ACs from both atmospheric pyrolysis (AP) and reduced pressure pyrolysis (RPP) were determined, and were found to fit the Langmuir type of isotherm.

The prepared ACs showed different adsorption properties and surface areas, and that AC obtained from apricot stones had the highest porosity, as indicating by IN and SABET.