Facile preparation of lignosulfonate induced silver nanoparticles for high efficient removal of organic contaminants in wastewater

In this study, sodium lignosulfonate (NaLS) was selected as a versatile regulator that possesses a three-function of reducer, dispersant and stabilizer for the preparation of silver nanoparticles (Ag NPs), to finally fabricate sodium lignosulfonate/ silver nanoparticles (NaLS@AgNPs) nanocatalysts. It was found that Ag NPs have the smallest particle size (15 ± 5 nm) and uniform distribution at the optimal NaLS concentration of 1.8 mM. Also, the NaLS@AgNPs nanocomposites exhibited excellent catalytic performance for the catalytic degradation of methylene blue (MB) (almost 100 % removal rate in only 150 s of reaction time, k = 20.4 × 10−3 s-1). A highest methyl orange (MO) removal rate in a H2O2 system as high as 90 % within 200 min with an apparent rate constant k = 4.04 × 10−3 min-1 can be achieved. This work provides a practical and facile one-step approach for preparing “ideal” noble metal nanocatalysts with the assistance of versatile and abundant sodium lignosulfonate derived from pulping process for purifying organic contaminant-containing wastewater with high catalytic degradation efficiency.