Aplicación de biopolímero basado en raquis de banano - polietilenglicol para adsorción de plomo y cadmio

Abstract

The renewable resources of lignocellulosic waste can be used for various processes that are environmentally friendly, and one of them is the adsorption of heavy metals in aqueous tributaries. This research aims at the removal of Pb2+ and Cd2+ metals in aqueous solution, using as an adsorbent material an agro-industrial residue from the rachis of banana. The banana is one of the main economic activities in our province and country, which generates large quantities of these wastes that are discarded by the farmer after the harvest, because the producers are only interested in the fruit (banana). This residue of banana rachis, due to its composition based on lignin, cellulose, holocelulosa and hemicellulose can be used in the adsorption of heavy metals in contaminated waters. For the development of adsorbent material, agro-industrial waste was collected from a farm located in El Guabo Canton and was taken to the research laboratories of the Technical University of Machala. The material in mention was cut, washed, dried and ground. For the transformation to polymerized biomass (BPEG), a previous treatment was performed where citrate buffer was added to PH 4.8, polyethylene glycol 4000 (PEG) and the cellulase enzyme, thus obtaining a material of greater reusability, greater stability and decrease the Cellulose content according to the pure spine, thus making the adsorbing material retain a higher percentage of lignin for effective removal of metals Pb2+ and Cd2+. The characterization of the material BPEG consisted in the determination of potential load zero, lignin by the standard TAPPI-T222, cellulose by the standard TAPPI-T203, Holocelulosa by the method ASTMD-1104. For its part, the evaluation of adsorption of PB2+ and Cd2+ was carried out several studies that included study of PH, isotherms of equilibrium, kinetics of adsorption and adsorption-desorption.