Pore Structure and Surface Functional Groups on Six Tropical Fruit Nutshell Active Carbons

摘要

Six fruit nutshells, namely: Thevetia nerrifolia, Hura crepitans, Hyphaene thebaica, Pentachlethra macrophyla, Teiracapidium conophorum and Cocos nucifera were carbonised, oxidized with atmospheric air and activated in CO_22 at 840deg C for 3 h. The iodine number range of active carbon (AC) was 822-1804 mg/g while BET surface area was within the 551-2738 m~2/g range. The ranges of micropore and mesopore volumes were 0.100-0.210 and 0.017-0.053 cmVg, respectively. The dependence of burn off, porosityand BET surface area of ACs on NaOH titratable surface functional groups indicated linearity. The phenol/lactone and carbonyl surface functional groups ranged from 6.002 to 8.294 and from 3.970 to 5.908 mmol H+ equiv/g carbon, respectively. FT-IR spectrarevealed the presence of OH, C=0, and C-0 functional groups on surface of the prepared ACs. Their SEM micrographs show pores and crevices all over their surface. These carbons might have potential ability to remove metals and organic compounds from waste water.