| Arsenic contamination is a dangerous global environmental problem, which d irectly affected human healthy, adsorption is the most common method for the removal of arsenic, and the research and development of adsorbent is the key process. Titanium dioxide for arsenic adsorption effect is good, strong stability, but the small particles, poor mechanical strength, difficult to realize the solid-liquid separation, if will be modified for the composite material is a kind of ideal solution In this paper, Graphene oxide was synthesized using Hummers method and GO was loaded on Ti O 2/ chitosan beads by chemical mixed. Ti O2/ chitosan/graphene oxide beads(GO/TICB) was used as adsorbent for removing As(?) and As(V) from aqueous solution and the adsorption characteristics of arsenic was also studied.Experimental research to the loading of graphite oxide, particle size and different dispersion the influence of preparation conditions on the removal of As(?), and the best catalyst preparation conditions were determined. Using electron microscope scanning environment(SEM), Zeta potential meter and BET specific surf ace area analyzer on the material microscopic appearance observation and analyzed. The adsorption kinetics and adsorption isotherm experiments, ultraviolet light, p H, interference ions on the influence of arsenic adsorption performance were studied, the effect of the recycle of composite particles is also investigated.Results show that the best condition of the preparation of adsorbent arsenic removal were 2.07% weight ratio of graphite oxide, the particle diameter of 1 mm, with 2.5% acetic acid solution for liquid dispersion; The analysis methods such as SEM, BET that graphene oxide load makes the particles on the surface of titanium dioxide is more apparent, and improve the specific surface area and porosity of materials; When p H < 7.2, adsorbent surface is positively charged, when the p H > 7.2, the surface of the adsorbent negatively charged; The maximum adsorption capacity can reach 12.43mg/g As(?) and 13.96mg/g As(V) and after modification of titanium dioxide/chitosan/graphene oxide composite particles under ultraviolet light. However, the maximum adsorption capacity just could reach 4.97 mg/g As(?) and 5.19mg/g As(V) without GO. The sorption processes coincided with the pseudo-second-order kinetic model and the adsorption isotherm could be well described by the Langmuir model. p H has a large effect on adsorption, with optimal performance at or below the PHPZC. Among all the common coexisting ions, phosphate ions showed interference on the adsorption of arsenic, due to the PO43- was the greatest competitor with arsenic for adsorptive site which has a similar chemical structure with arsenic acid radical in the water. Composite particles adsorption of Arsenic 10.98 mg, 10.57 mg/g and 10.43 mg/g and 10.06 mg/g, shows that composite particles hav e good regeneration performance after four times cycle. We can rationally expect this novel composite bead to be an effective and prospect adsorbent for the removal of Arsenic from water. |
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