Zinc adsorption from aqueous solutions using disposal sheep manure waste (SMW)

Available and disposal low price adsorbent (i.e. sheep manure waste (SMW)) was used for adsorption studies of Zn2+ from aqueous solutions. The adsorption experiments were performed under various conditions such as different adsorbent particle size (0.064-1.0 mm), Zn2+ initial concentration (20-150 ppm), shaking time (1-300 min), pH (1-6), and adsorbent concentration (2-30 g/l). About 10 g/l of SMW (0.064 mm in diameter) was found to be enough to remove 93.3% of 100 ppm Zn2+ from 50 ml aqueous solution after 1 h. The optimum pH value was found to be at 4. The kinetic curves show very clearly the selectivity of the SMW for Zn2+. The uptake obeys both the Freundlich and Langmuir isotherms. The applicability of Lagergren kinetic model has also been investigated. Activated carbon was also prepared by heating a grinded SMW at (105-800 degreesC) and the adsorption capacity is investigated. About 10 g/l of activated (heated to 600 degreesC) SMW was enough to remove 98.8% of 100 ppm Zn2+ from 50 ml aqueous solution after 5 h. (C) 2001 Elsevier Science B.V. All rights reserved.