研究水体系中亚甲基蓝的光化学降解。结果表明,在高压汞灯照射下,亚甲基蓝在人工海水中降解得最快,蒸馏水次之,而在天然海水中降解得最慢。通过对比研究发现,重金属离子(Cu^2+,Zn^2+,Cd^2+,Hg^2+)和腐殖酸能够在一定程度上抑制亚甲基蓝的光降解;而丙酮能促进亚甲基蓝的光降解。由此可见,重金属离子和腐殖酸可能是造成亚甲基蓝在天然海水中降解缓慢的主要因素之一。
In this paper, the photochemical degradation of methylene blue (MB) was studied in distilled water, artificial seawater and seawater. The photolysis rate of MB in natural seawater was slower than that in distilled water and artificial seawater. In addition, the result shows that the addition of heavy metal ions such as Cu^2 +, Pb^2+, Cd^2 +, Hg^2 + and humic acidto the aqueous solutions can decelerate the photodegradation of MB, while acetone can accelerate the reaction. This shows that heavy metal ions and humic acid may be one of main factors which slow down the photolysis rate of MB in seawater.