催化动力学褪色光度法测定煤炭工业废水排放中痕量铬(Ⅵ)的研究

Catalytic Kinetic Spectrophotometric Determination of Trace Cr(Ⅵ)in Coal Industry Wastewater

实验利用催化动力学褪色光度法测定煤炭工业废水排放中痕量Cr(Ⅵ)的研究反应在缓冲溶液NH_3-NH_4Cl中,加入表面活性剂SDS,利用3,3'-二甲基酚酞在Cr(Ⅵ)催化作用下发生褪色反应,从而研究出煤化工废水中痕量Cr(Ⅵ)新的实验测定方法,即利用催化动力学分光光度法测定痕量Cr(Ⅵ),该实验测定方法表明Cr(Ⅵ)的质量浓度在0.03~0.35μg/m L的范围内与吸光度差△A值呈现出较好的线性关系,线性回归方程为:△A=0.9843ρ_(Cr(Ⅵ))(μg/m L)+0.1704,相关系数r=0.9889,检出限C_(L)=2S_(eb)/K=6.41×10^(-4)mg/L,该方法可直接用于煤化工企业达标废水中痕量铬的测定。

Cr(Ⅵ)in wastewater from the coal industry is getted by catalytic kinetic decoloration spectrophotometry.The mass concentration of Cr(Ⅵ)is evaluated by the catalytic oxidation reaction of 3,3'-dimethylphenolphthalein under Cr(Ⅵ)catalysis after adding surfactant sodium dodecyl sulfonate(SDS)into buffer solution ammonia-ammonium chloride(NH3-NH4Cl).The results show that when the mass concentration of(Ⅵ)is in the range of 0.03-0.35μg/mL,the relationship betweenρCr(Ⅵ)and the difference value in absorbance(ΔA)isΔA=0.9843ρCr(Ⅵ)+0.1704.The correlation coefficient r is 0.9889,and the detection limit CL is 6.41×10^(-4) mg/L,which can be directly used for the determination of trace chromium in the wastewater of coal chemical enterprises.