中文摘要：

使用离子色谱测脱硫脱硝副产物中的亚硫酸根、硫酸根、亚硝酸根、硝酸根4种离子,研究通过加甲醛抑制亚硫酸根的氧化,研究甲醛对4种离子,以及4种离子之间在测定时是否会相互影响。结果发现：硫酸根、亚硝酸根、硝酸根3种离子比较稳定,而SO3^2-易被氧化。发现采用甲醛作为抗氧化剂可以较好地抑制SO3^2-的氧化;用1 mmol/L的KOH作为淋洗液时,甲醛的质量分数可选为0.05%,若甲醛浓度过高,除影响色谱柱寿命外,SO3^2-的出峰面积也会变小。甲醛的加入不影响亚硝酸根和硝酸根的出峰。亚硫酸根、硫酸根、亚硝酸根、硝酸根同时测定过程中相互干扰不大,4种离子的线性关系较好。采用甲醛做抗氧化剂时,不应采用Na2CO3等弱碱溶液作为淋洗液。总之,通过加入适量的甲醛,离子色谱法可以准确同时测定脱硫脱硝产物的亚硫酸根、硫酸根、亚硝酸根、硝酸根4种离子。

英文摘要：

Ion chromatography was used for measurement of sulfite,sulfate,nitrate and nitrite ions that leaching from the by products of simultaneous desulfurization and denitrification by calcium based sorbent. The study focused on the stability of single ions and interactions of the four kinds of ions. It is found that sulfate,nitrate and nitrite ions were stable,however,sulfite ion could be easily oxidized. Formaldehyde was used as stabilizing agent to prevent sulfite ion effectively from being oxidized effectively. However,the mass percentage of formaldehyde should be less than 0. 05% when KOH solution is used as the pour lotion,since excess formaldehyde would decrease SO3^2-peak area and also had negative effect on the chromatographic column. Formaldehyde had no effect on the measurement of nitrate and nitrite ions. During the determination process,it was found that these four ions had little interference,and all ions showed good linearity. If alkalescent solution（ like Na2CO3） was used as pour lotion,formaldehyde should not be used as oxidation inhibitor. In conclusion,sulfite,sulfate,nitrate and nitrite ions could be accurately determined by ion chromatography with addition of proper dosage of formaldehyde in the solution.