| Summary: | 碩士 === 國立臺北科技大學 === 環境工程與管理研究所 === 107 === Aluminum sulfate coagulants and poly aluminum chloride are widely used in
water purification equipment as chemicals in wastewater treatment. It was found that the treated water still has residual traces of aluminum ions. If the drinking water has soluble aluminum, it affects to human health. According to the drinking water standards by the World Health Organization (WHO), the maximum allowable concentration of total aluminum is 0.2 mg/L. In this study, self made chitin and cation exchange resins(Na+-R) are selected as adsorbents for the removal of aluminum.
The results show that in SEM analysis, self made chitin in aluminum solution at pH 6.5, the formation of needle like crystal structure on the surface of chitin containing aluminum is used. It prove s to the presence of adsorbed aluminum ions. In XRD analysis, the characteristic peak appears at chitin 2θ=19.17 ﾟ, which is similar to chitin by literature. In FTIR analysis, functional groups of chitin are mainly C, H, O, and N. In BET analysis, self made chitin h as a specific surface area of 0.472 m 2 /g, a pore volume of 0.000075 cm 3 /g, and an average pore diameter of 1.82 nm. In the batch experiments, the result of aluminum concentration, under the condition of pH 6 solution, exceeds to the regulatory standard concentration of 0.3 mg/L, which proves that aluminum is supersaturated. The effect of filtered and unfiltered water proves that Aluminum water at pH 6~7.5 easily produces Al(OH)3(S) precipitate. In the influence of pH value, the optimum pH condition of cation exchange resin (Na+-R) is pH 6, and the optimum pH condition of self made chitin is pH 5~7. The continuous experimental results of the column show that the maximum adsorption capacity of cation exchange resin (Na+-R) is 23.92 mg/g at pH 5. The maximum adsorption capacity of self made chitin is 12.26 mg/g at pH 6. The maximum adsorption capacity of self made chitin is 28.94 mg/g at pH 7.
In conclusion, self-made chitin and cation exchange resins (Na+-R) can
successfully remove aluminum concentration below the WHO standard (<0.2 mg / L).
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