Enhanced adsorption capacity and selectivity towards molybdenum in wastewater by a persimmon tannin waste based new adsorbent

Abstract

Taking advantage of their voluminous availability as agricultural or industrial waste and ease of chemical modification, it is always a promising strategy to fabricate waste biomass materials as adsorbents for selective uptake of concerned metal ions. In the present paper, an environmentally "green" adsorbent was developed by introduced triethylamine (TEA) group on persimmon waste and its potentiality for adsorption, desorption behavior, and mechanism of molybdenum were evaluated. RESULTS: As compared to the persimmon tannin waste based other adsorbents, TEA-CPT gel exhibited reasonable uptake capacity (287.21mgg-1) and selectivity for the adsorption of molybdenum. Chelation action between the O-atom of molybdenum poly-anions and the N-atom of tertiary amine is considered to be responsible for selective binding and sorption of molybdenum over co-existing metal ions. In addition, the adsorbed molybdenum was very effectively eluted with low concentration NH3H2O solution (1%) in column experiment and the regenerated adsorbent exhibited undiminished sorption efficiency for at least six cycles. CONCLUSION: Results show that the TEA-CPT gel modified by triethylamine has the good stability and the selectivity, etc make it a promising candidate for selective recovery of molybdenum from aqueous system.