烟气SO2与氧化锌在水溶液中的反应研究

以氧化锌为吸收剂的烟气脱硫工艺能实现硫、锌资源的回收利用,特别适合于铅锌冶炼行业的烟气净化。试验研究了氧化锌与SO2在水溶液中的反应过程。通过固、液相中亚硫酸盐含量,锌离子浓度以及溶液pH值等对反应过程进行了表征,考察了SO2浓度、温度对反应的影响。试验结果表明,SO2在水溶液中首先是与氧化锌反应生成固体亚硫酸锌,然后固体亚硫酸锌溶解进入液相。当SO2水溶液w(SO2)1%以上时,25～35℃的反应温度对于提高SO2吸收率有利,进一步的表观反应活化能分析表明,氧化锌和SO2水溶液的反应活性与Ca(OH)2和SO2水溶液的反应活性相似。

Study on reaction of zinc oxide with SO2 in aqueous solution

The recycling of sulphur and zinc can be realized by a process using zinc oxide as the absorbent, which is especially suitable for flue gas desulphurization in lead-zinc metallurgical industry. The reaction of zinc oxide with SO2 in aqueous solution was studied in laboratory. The sulphite content in solid and solution, Zn2~ concentration and pH of solution were used to characterize the reaction and the effects of SO2 concentration and temperature on reaction were examined. The results showed that S02 in aqueous solution first reacted with zinc oxide to form zinc sulphite solid, which then dissolved in aqueous solution. At the SO2 concentration of above 1% wt, the temperature of 25 - 35 ℃ was favorable for SO2 conversion. The further analysis of apparent activation energy showed that the reactivity of zinc oxide with SO2 in solution was similar to that of Ca（OH） 2.