Activated carbon from peach stones (ACPS) was prepared by two-step procedure of carbonization and activation, using a stainless-steel vertical reactor and a tube furnace. The raw material was subjected to pyrolysis at 823 K (heating rate of 5 K/min) for 30 min. The obtained carbonizate was activated with water vapour at 1123 K for 1 h. The activated carbons from apricot stones (ACAS), grape seed (ACGS) and olive stones (ACOS) were prepared by onestep process, combining carbonization and activation procedure [43e45]. The raw materials were subjected to pyrolysis in the presence of water vapour for 1 h at 1073 K for ACAS, 973 K for ACGS and 1023 K for ACOS.