Degradation of Lignin Pollutants by Persulfate Activated with a Graphene Oxide Loaded Cu-2(OH)(3)NO3 Composite

Graphene oxide (GO)-Cu-2(OH)(3)NO3 composite was prepared by a thermal calcination process and evaluated as an effective heterogeneous catalytic material. The composite displayed prominent activated performance to persulfate, which was influenced by preparation condition and the reaction parameters in catalytic system. Under optimal reactive conditions, the GO-Cu-2(OH)(3)NO3 composite yielded rapid degradation of ferulic acid, which the corresponding apparent rate constant was 1.12x10(-1) min(-1). Catalytic mechanism analysis showed that the main oxygen species were (SO4-)-S-center dot and (OH)-O-center dot. Among them, (OH)-O-center dot made the main contribution in the catalytic system. The analysis of degradation intermediates of ferulic acid showed that the compound could be mineralized to small molecules. The remarkable enhanced heterogeneous catalytic performance of GO-Cu-2(OH)(3)NO3 was due to a larger specific surface area, high adsorption capacity and a high mass transfer efficiency of oxidizing radicals in the reactive system.