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Arsenic has been classified as one kind of carcinogens.Excessive intake of arsenic can cause risks to human body and lead to several diseases.Arsenic pollution in water is universal resulting from weathering of rocks,mining,metallurgy,and pesticides usage.To develop effective adsorbents for arsenic removal from water with high efficiency will be very helpful for water treatment.Many absorbents including nanomaterials have been applied to remove arsenic for their specific physical and chemical properties.However,nanomaterials used in many cases are difficult to separate from water for reuse or disposal.The normal adsorbents are lack of specificity and with low adsorption capacity for arsenic.In this study,carbon nanotubes were used as a plate for nanocomposites synthesis.First,carbon nanotubes were modified by acid(HNO3),and then iron oxides were loaded to achieve magnetic carbon nanotubes.Later on,the synthesized magnetic carbon nanotubes were modified by zirconium oxides to enhance the adsorption specificity and efficiency.The synthesized nanocomposites were used as adsorbent for arsenic removal from water.The experimental conditions including pH,equilibration time,temperature,arsenic concentrations were investigated.Static adsorption experiment study showed that when solution pH was 2 at 50 ℃,adsorption equilibrium could reach in 5 hours.Under the optimized conditions,the maximum adsorption capacity of the composites was 22 mg/g.The adsorption process fitted Langmuir isotherm adsorption model.Based on the adsorption thermodynamics and adsorption dynamics analysis,the adsorption was described as endothermic reaction and secondary adsorption dynamics process.