Preparation of Activated Carbon from Lapsi Seed Stone and its Application for the Removal of Arsenic from Water

Abstract

In this paper, Guaranteed Services Token (GuST) protocol for integrated Adsorption of arsenic by activated carbon prepared from locally available Lapsi seed stone is presented. Activated carbon has been prepared by carbonization of Lapsi seed stone (chorespondias axillaris, Roxb) in a nitrogen atmosphere at 400°C. Chemical activation using a 1:1 ratio of Lapsi seed stone powder and zinc chloride followed by iron impregnation greatly enhanced the arsenic adsorption capacity for adsorption of arsenic from ground water. Activated carbon of dose 2g/L decreased the concentration of arsenic in water from 800 ppb to below the interim guide line value of 50 ppb of arsenic in drinking water of Nepal. The iodine number of raw carbon is quite low but chemical activation using 1:1 Lapsi seed powder and zinc chloride at 400°C increased the iodine number to 791mg/g. Iron impregnated activated carbon prepared from locally available Lapsi seed stones can be used in community level at point- of- use for treatment of arsenic contaminated ground water.Key words: activated carbon; Arsenic removal; Adsorption; Chorespondias axillaris; Iron impregnated carbonDOI: http://dx.doi.org/10.3126/jie.v8i1-2.5113Journal of the Institute of Engineering Vol. 8, No. 1&2, 2010/2011Page: 211-218Uploaded Date: 20 July, 2011