将含有锌元素的纸和纸板经浓硫酸与过氧化氢溶解后,根据溶液中锌离子与锌试剂的显色反应,采用紫外-可见分光光度法测定纸和纸板中锌含量.结果表明,在pH值为8.9、锌试剂用量为5mL时,锌离子与锌试剂在620 nm处的吸光度与锌离子含量呈良好的线性关系,相关系数为0.9991,检出限为0.0720 mg/L,标准加入回收率为94.9％ ～ 104.6％,可采用紫外-可见分光度法对钢纸内锌含量进行检测.%Dissolving the paper or paperboard by concentrated sulfuric acid and hydrogen peroxide solution and then the zinc content was determined by ultraviolet-visible spectrophotometry based on the color reaction between zinc ion and zincon. The results showed that the zinc content and the absorbance at 620 run showed a good linear relationship when the pH value is 8.9 and the zincon volume is 5 mL, and the linear correlation coefficient is 0.9991. The detection limit is 0.0720 mg/L and the standard addition recoveries are 94.9% ~ 104.6%. The zinc content in a vulcanized paper sample determined by this method is well in accord with that determined by other methods. Hence, this method can be used to determine the zinc content in paper quantitatively.
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