Cu2+催化过硫酸钾氧化吸收气态汞

引言 Lipfert等1]认为1000 MW电站锅炉排放的汞可使附近居民食用鱼中甲基汞水平增加一倍.由于甲基汞在环境中的挥发性、持久性和生物累积性以及对神经的影响,因此,在1990年的美国空气清洁法案(CAAA)中,汞受到了极大的关注.

Hg oxidative absorption in potassium persulfate solution catalyzed by Cu2+

The objective of the study is to examine the conditions under which transition metal ion,Cu²⁺ could catalyze potassium persulfate to oxidize gaseous mercury.The effects of the concentrations of potassium persulfate and copper sulfate，and addition of sodium thiosulfate and tertiary butanol（TBA），a free radical scavenger on the efficiency of Hg removal were studied.The results showed that the efficiency of Hg removal increased with increasing concentrations of potassium persulfate，copper sulfate and the addition of sodium thiosulfate，while decreased with the addition of TBA.The oxidation reaction between Hg and K₂S₂O₈ catalyzed by Cu²⁺ followed pseudo-first-order kinetics.Direct rate constant and catalyzed rate constant were 3.52×10^-5s^-1 and 0.0927 L·mol^-1·s^-1，respectively.Furthermore，the possible reaction mechanism of gaseous mercury oxidation was also discussed.Cu²⁺ was considered as an effective complex anion activator in persulfate-thiosulfate redox system and Hg removal can be achieved by both indirect oxidation of free radicals and direct oxidation by persulfate.