Preparation Of Spore@Ti⁴⁺ Microspheres And Its Application In The Adsorption Of Arsenic From Water Environment

Arsenic is one of the top 20 hazardous substances around the world.The problem of arsenic pollution is harmful and has caused the attention of the whole world.Long-term exposure to arsenic may cause series diseases,like the cancers of lung,bladder,kidney and skin.How to remove arsenic efficiently from aquatic environment is an urgent problem in the worldwide.In this study,we adopted spore@Ti⁴⁺ microspheres as a novel adsorbent for the removal of As???and As???.The characteristics of the adsorbents were studied by TEM,SEM,FTIR,XPS and Zeta potential analysis.The results indicate that the spore@Ti⁴⁺ microspheres are stable,uniform and well disperse in water phase.The effect of initial pH and coexisting anions has been investigated and we found that under the alkaline condition is favorable for the adsorption of As???while acidic condition is favorable for As???.The existence of SO₄^2–,Cl– and NO₃^– didn't affect the adsorption of As???and As???;however,high concentration of HCO₃^– and HPO₄^2– show deferent effect on the adsorption of As???and As???.The kinetic studies show that both the adsorption process can reach equilibrium in a short time?15 min?and fit well by pseudo-second-order kinetic model.The adsorption isotherms studies demonstrate that the adsorption of As???and As???can be well described by Freundlich model and the maximum adsorption capacity of As???and As???are higher than 97.26 mg g^–1 and 137.01 mg g^–1,respectively.FTIR and XPS analysis suggest that the Ti–OH and –NH₃⁺ groups on the surface of spore@Ti⁴⁺ microspheres play the main role in the adsorption.The adsorption–desorption–regenerate–reuse experiments demonstrated that spore@Ti⁴⁺ microspheres can be regenerated and remain high adsorption capacity.Furthermore,the adsorption studies in real sample never show a decrease on adsorption capacity,which suggest the high potential of it in practical application.