消除DPD法测定水中臭氧浓度干扰因素的研究

Investigation on Eliminating Interference in the Determination of Ozone Concentration in Aqueous Solutions by DPD Method

研究了Ｈ_２Ｏ_２和其它氧化剂（以过氧化苯甲酰为例）对ＤＰＤ法测定水中臭氧浓度的干扰作用，结果表明，随着ＫＩ浓度或显色时间的增加，Ｈ_２Ｏ_２和其它氧化剂的干扰作用增加，当ＫＩ浓度为０．５ｇ／Ｌ时，可以基本消除这些干扰作用，且当臭氧浓度低于０．６ｍｇ／Ｌ时，不影响臭氧对ＤＰＤ的显色作用。

The interference from hydrogen peroxide and other oxidants (benzoyl peroxide) in the determination of ozone concentration in aqueous solutions by DPD method have been investigated.The experimental results showed that the interference increased with the increment of potassium iodide concentration or color developing time;however,when potassium iodide concentration was as low as 0.5g/L,the interference could be essentially eliminated;and when ozone concentration was below 0.6mg/L,the color developing reaction of DPD with ozone was not interfered.