Effective removal of chlorinated organic pollutants by bimetallic iron-nickel sulfide activation of peroxydisulfate

Chlorinated organic pollutants(COPs)have caused serious contaminants in soil and groundwater,hence developing methods to remove these pollutants is necessary and urgent.By a simple hydrothermal method,we synthesized the bimetallic iron-nickel sulfide(FeNiS)particles which exhibited excellent catalytic property of COPs removal.FeNiS was chosen as the peroxydisulfate(PDS)activator to removal COPs including 4-chlorophenol(4-CP),1,4-dichlorophenol(1,4-DCP)and 2,4,6-trichlorophenol(2,4,6-TCP).The results show that FeNiS can efficiently activate PDS to produce sulfate radical(SO4·-)which plays major role in the oxidative dechlorination and degradation due to its strong oxidizing property and the ability of producing hydroxyl radicals(·OH)in the alkaline condition.Meanwhile,the Cl-abscised from COPs during the dechlorination can turn into the chlorine radicals and enhance the degradation and cause further mineralization of intermediate products.This bimetallic FeNiS catalyst is a promising PDS activator for removal of chlorinated organics.

Surfactant-assisted removal of 2,4-dichlorophenol from soil by zero-valent Fe/Cu activated persulfate

The organic compounds contaminated soil substantially threatens the growth of plants and food safety.In this study,we synthesis zero-valent bimetallic Fe/Cu catalysts for the degradation of 2,4-dichlorophenol(DCP)in soils with persulfate(PS)in combination of organic surfactants and exploring the main environmental impact factors.The kinetic experiments show that the 5%(mass)dosage of Fe/Cu exhibits a higher degradation efficiency(86%)of DCP in soils,and the degradation efficiency of DCP increases with the increase of the initial PS concentration.Acidic conditions are favorable for the DCP degradation in soils.More importantly,the addition of Tween-80,and Triton-100 can obviously desorb DCP from the soil surface,which enhances the degradation efficiency of DCP in soils by Fe/Cu and PS reaction system.Furthermore,the Quenching experiments demonstrate that SO_(4)^(-1)·and·OH are the predominant radicals for the degradation of DCP during the Fe/Cu and PS reaction system as well as non-radical also exist.The findings of this work provide an effective method for remediating DCP from soils.