Synchronous Removal Of Arsenate And Chromium From Water By Macroporous Anion Exchanger-Supported Nano-hydrated Ferric Oxide(HFO)

In recent years,because of the dangers of the wastewater generated from mining and smelting process,the treatment of this wastewater,in which As(V)and Cr(VI)are usually coexisting,has attracted increasing attention.In this study,a new type of multi-functional adsorbent HFO-201 was synthesized by incorporating hydrated ferric oxides(HFO)inside the macroporous basic anion exchange resin(D201).The obtained nanocompositeis believed of ability for removing arsenic and chromium simultaneously.In the study of remove Cr(VI)in the sole system,HFO-201 can stable remove Cr(VI)in the range of the pH=3-10.With the increase of pH,the adsorption of Cr(VI)was reduced;At PH=7.0,the biggest adsorption capacity is 144.3 mg/g.The adsorption equilibrium reached within 150min.The coexistence ions won't influence the removal of Cr(VI).A 10 batch adsorption-regeneration cycle experiment show that HFO-201 can be regenerated by alkali liquor.The results suggest that HFO-201 is a kind of effective adsorbent to remove Cr(VI).Effect of different As(V)/Cr(VI)(mass ratio),pH,and contact time on HFO-201 adsorption of arsenate and chromium in binary system was examined.Results indicate that adsorption of arsenic anions has improved significantly with HFO-201.Furthermore,HFO-201 has fast adsorption rate to both As(V)and Cr(VI),and can be used repeatedly.In column experiment,only little influence was observed on the adsorption by the large number of competing anions(SO42-,Cl-,NO3-) in influent.