Author
Lima, Isabel | |
Marshall, Wayne |
Submitted to: Journal of Residuals Science & Technology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/1/2007 Publication Date: 1/1/2007 Citation: Lima, I.M., Marshall, W.E. 2007. Production of granular activated carbons from pig manure for metal ions adsorption. Journal of Residuals Science & Technology. 4(1):9-16 Interpretive Summary: The current method of processing pig waste involves diluting it into large lagoons, which carries both environmental and human health risks. Alternatives to pig waste disposal are its reuse into value added products. This study produces activated carbons from swine manure and characterizes them in terms of physical, chemical and adsorptive properties. The process involves pyrolyzing and activating dry pelletized swine manure under conditions effective to produce activated carbon. When compared to reference carbons made from coal, coconut shells or wood, experimental carbons were superior in their ability to adsorb metal ions, adsorbing two to three times more copper ion than their plant based counterparts and up to eight times more than carbons made from coal. Swine manure-based carbons demonstrated a preference towards ions of copper, followed by zinc and cadmium. It is postulated that negatively charged phosphate groups attached to the carbon skeleton are, at least in part responsible for their increased affinity towards positively charged metal ions. Technical Abstract: The current method of processing pig waste involves diluting it into large lagoons, which carries both environmental and human health risks. Alternatives to pig waste disposal are its reuse into value added products. This study produces activated carbons from swine manure and characterizes them in terms of physical, chemical and adsorptive properties. The process involves pyrolyzing and activating dry pelletized swine manure under conditions effective to produce activated carbon. Brunauer-Emmett-Teller, BET surface areas for the resulting granular activated carbons ranged between 342 and 456 m2/g but no relationship was found between BET and adsorption. When compared to reference carbons made from coal, coconut shells or wood, experimental carbons were superior in their ability to adsorb metal ions, adsorbing two to three times more copper ion than their plant based counterparts and up to eight times more than carbons made from coal. Swine manure-based carbons demonstrated a preference towards ions of copper, followed by zinc and cadmium. It is postulated that negatively charged phosphate groups attached to the carbon skeleton are, at least in part responsible for their increased affinity towards positively charged metal ions. |