A high-performance polymer hydrogel derived from konjac flying powder for removal of heavy metals

Agricultural byproducts have excellent potential for pollutant remediation due to their low-cost and environmental sustainability. Konjac flying powder (KFP) is a fine particulate byproduct of the production of konjac glucomannan, accounting for 30-40 wt% of the total raw materials. In this work, KFP was modified by free radical grafting copolymerization with acrylic acid, methacrylic acid and N , N ′-methylene bis(acrylamide). The lightly crosslinked product demonstrated excellent adsorption performance for heavy metals, with the maximum adsorption capacity for Cd( ii ), Pb( ii ) and Cu( ii ) reaching 635 mg g −1 , 812 mg g −1 , and 855 mg g −1 , respectively, under optimized conditions. The adsorption isotherm of heavy metal ions fitted well with the Langmuir model. Moreover, the adsorption performance was nearly unchanged after several adsorption-desorption cycles, suggesting that polymeric derivation of KFP has great potential for the remediation of heavy metal pollution. Agricultural byproducts have excellent potential for pollutant remediation due to the low-cost and environmental sustainability.