Superior trichloroethylene removal from water by sulfide-modified nanoscale zero-valent iron/graphene aerogel composite

Sulfide-modified nanoscale zero-valent iron(S-nZVI) is a promising material for removal of organic pollutants from water, but S-nZVI nanoparticles(NPs) easily agglomerate and have poor contact with organic contaminants.Herein, we propose a new S-nZVI/graphene aerogel(S-nZVI/GA) composite which exhibits superior removal capability for trichloroethylene(TCE) from water.Three-dimensional porous graphene aerogel(GA) can improve the efficiency of electron transport, enhance the adsorption of organic pollutants and restrain the agglomeration of the core-shell S-nZVI NPs.The TCE removal rates of Fe S, nZVI, GA and S-nZVI were 27.8%, 42%, 63% and 75% in 2 hr, respectively.Furthermore, TCE was completely removed within 50 min by S-nZVI/GA.The TCE removal rate increased with increasing p H and temperature, and TCE removal followed the pseudo-first-order kinetic model.The results demonstrate the great potential of S-nZVI/GA composite as a low-cost,easily separated and superior monolithic adsorbent for removal of organic pollutants.