A study on simultaneous removal of NO and SO2 by using sodium persulfate aqueous scrubbing

Abstract Nitric oxide (NO) removal and sulfur dioxide (SO 2 ) removal by sodium persulfate (Na 2 S 2 O 8 ) were studied in a Bubble Column Reactor. The proposed reaction pathways of NO and SO 2 removal are discussed. The effects of temperatures (35–90 °C), Na 2 S 2 O 8 (0.05–0.5 mol·L − 1 ), FeSO 4 (0.5–5.0 m mol·L − 1 ) and H 2 O 2 (0.25 mol·L − 1 ) on NO and SO 2 removal were investigated. The results indicated that increased persulfate concentration led to increase in NO removal at various temperatures. SO 2 was almost completely removed in the temperature range of 55–85 °C. Fe 2 + accelerated persulfate activation and enhanced NO removal efficiency. At 0.2 mol·L − 1 Na 2 S 2 O 8 and 0.5–1.0 mmol·L − 1 Fe 2 + , NO removal of 93.5%–99% was obtained at 75–90 °C, SO 2 removal was higher than 99% at all temperatures. The addition of 0.25 mol·L − 1 H 2 O 2 into 0.2 mol·L − 1 Na 2 S 2 O 8 solution promoted NO removal efficiency apparently until utterly decomposition of H 2 O 2 , the SO 2 removal was as high as 98.4% separately at 35 °C and 80 °C.