Authors: I Frutos C GarcíaDelgado A Gárate E Eymar
Publish Date: 2016/09/10
Volume: 13, Issue: 11, Pages: 2713-2720
Abstract
The use of agricultural wastes as biosorbents is gaining importance in bioremediation of heavy metalpolluted water and soils due to their effectiveness and low cost This work assesses the Cd Pb and Cu adsorption capacity of the raw materials used in the production of substrates for mushroom production Agaricus bisporus and Pleurotus ostreatus and the spent mushroom composted SMC based on the functional groups of their organic carbon The raw materials studied included agricultural wastes wheat straw wheat and rice poultry litter grape pomace and inorganic substances gypsum and calcareous sand Organic carbon from wastes and their composting products were characterized by CPMAS 13C NMR Langmuir adsorption isotherms of metals were plotted for each raw material composting step spent A bisporus and P ostreatus substrates and the final SMC The maximum adsorption capacities of SMC were 4043 1516 and 362 mg g−1 for Cd Pb and Cu respectively The composting process modified the adsorption properties of raw materials because of the enhanced adsorption of Cd and Cu and decreased adsorption capacity of Pb CPMAS 13C NMR and potentiometric titration were used to identify the functional groups of the organic carbon responsible for the metal adsorption The content of cellulose was correlated with Pb adsorption p 0001 alkyl and carboxyl carbon with Cd adsorption p 0001 and Nalkyl p 0001 and carboxyl p 0010 groups with Cu adsorption These results are valuable to develop new biosorbents based on agricultural wastes and demonstrate the high potential of SMC to adsorb heavy metals from polluted environments
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