Effect of ammonium sulfate and urea on PCDD/F formation from active carbon and possible mechanism of inhibition  

作　　者：Mi Yan Zhifu Qi Jie Yang Xiaodong Li Jianli Ren Zhang Xu 

机构地区：[1]Institute of Energy and Power Engineering, Zhejiang University of Technology [2]State Key laboratory of Clean Energy Utilization, Zhejiang University

出　　处：《Journal of Environmental Sciences》2014年第11期2277-2282,共6页环境科学学报（英文版）

基　　金：supported by the Major State Basic Research Development Program of China (973 Program) (No. 2011CB201500);the National High Technology Research and Development Program of China (No. 2012AA062803)

摘　　要：The effect of ammonium sulfate （（NH4）2SO4） and urea （CO（NH2）2） on polychlorinated dibenzo-p-dioxin and dibenzofuran （PCDD/F） formation from active carbon was investigated in this study. Both additives could significantly inhibit PCDD/F formation, and PCDD/F （TEQ） generation was reduced to 98.5% （98%） or 64.5% （77.2%） after 5% （NH4）2S04 or CO（NH2）2 was added into model ash, respectively. The inhibition efficiency of PCDDs was higher than the value of PCDFs, however, the reduction of PCDD/F yield was mainly from PCDFs decreasing. In addition, the solid-phase products were reduced more than the gas-phase compounds by inhibitors. By the measurement of chlorine emission in the phase of ion （Cl[Cl^-]） and molecule gas （Cl[Cl2]）, it was observed that both Cl[Cl^-] and Cl[Cl2] were reduced after inhibitors were added into ash. Cl[Cl2] was reduced to 51.0% by urea addition, which was supposed as one possible mechanism of PCDD/F inhibition.The effect of ammonium sulfate （（NH4）2SO4） and urea （CO（NH2）2） on polychlorinated dibenzo-p-dioxin and dibenzofuran （PCDD/F） formation from active carbon was investigated in this study. Both additives could significantly inhibit PCDD/F formation, and PCDD/F （TEQ） generation was reduced to 98.5% （98%） or 64.5% （77.2%） after 5% （NH4）2S04 or CO（NH2）2 was added into model ash, respectively. The inhibition efficiency of PCDDs was higher than the value of PCDFs, however, the reduction of PCDD/F yield was mainly from PCDFs decreasing. In addition, the solid-phase products were reduced more than the gas-phase compounds by inhibitors. By the measurement of chlorine emission in the phase of ion （Cl[Cl^-]） and molecule gas （Cl[Cl2]）, it was observed that both Cl[Cl^-] and Cl[Cl2] were reduced after inhibitors were added into ash. Cl[Cl2] was reduced to 51.0% by urea addition, which was supposed as one possible mechanism of PCDD/F inhibition.

关 键 词：Inhibition PCDD/Fs Ammonium sulfate Urea Chlorine emission 

分 类 号：X701[环境科学与工程—环境工程]