TY - JOUR
T1 - Effect of Nitrogen Oxides on Elemental Mercury Removal by Nanosized Mineral Sulfide
AU - Li, Hailong
AU - Zhu, Lei
AU - Wang, Jun
AU - Li, Liqing
AU - Lee, Po Heng
AU - Feng, Yong
AU - Shih, Kaimin
PY - 2017/8/1
Y1 - 2017/8/1
N2 - Because of its large surface area, nanosized zinc sulfide (Nano-ZnS) has been demonstrated in a previous study to be efficient for removal of elemental mercury (Hg0) from coal combustion flue gas. The excellent mercury adsorption performance of Nano-ZnS was found to be insusceptible to water vapor, sulfur dioxide, and hydrogen chloride. However, nitrogen oxides (NOX) apparently inhibited mercury removal by Nano-ZnS; this finding was unlike those of many studies on the promotional effect of NOXon Hg0removal by other sorbents. The negative effect of NOXon Hg0adsorption over Nano-ZnS was systematically investigated in this study. Two mechanisms were identified as primarily responsible for the inhibitive effect of NOXon Hg0adsorption over Nano-ZnS: (1) active sulfur sites on Nano-ZnS were oxidized to inactive sulfate by NOX; and (2) the chemisorbed mercury, i.e., HgS, was reduced to Hg0by NOX. This new insight into the role of NOXin Hg0adsorption over Nano-ZnS can help to optimize operating conditions, maximize Hg0adsorption, and facilitate the application of Nano-ZnS as a superior alternative to activated carbon for Hg0removal using existing particulate matter control devices in power plants.
AB - Because of its large surface area, nanosized zinc sulfide (Nano-ZnS) has been demonstrated in a previous study to be efficient for removal of elemental mercury (Hg0) from coal combustion flue gas. The excellent mercury adsorption performance of Nano-ZnS was found to be insusceptible to water vapor, sulfur dioxide, and hydrogen chloride. However, nitrogen oxides (NOX) apparently inhibited mercury removal by Nano-ZnS; this finding was unlike those of many studies on the promotional effect of NOXon Hg0removal by other sorbents. The negative effect of NOXon Hg0adsorption over Nano-ZnS was systematically investigated in this study. Two mechanisms were identified as primarily responsible for the inhibitive effect of NOXon Hg0adsorption over Nano-ZnS: (1) active sulfur sites on Nano-ZnS were oxidized to inactive sulfate by NOX; and (2) the chemisorbed mercury, i.e., HgS, was reduced to Hg0by NOX. This new insight into the role of NOXin Hg0adsorption over Nano-ZnS can help to optimize operating conditions, maximize Hg0adsorption, and facilitate the application of Nano-ZnS as a superior alternative to activated carbon for Hg0removal using existing particulate matter control devices in power plants.
UR - http://www.scopus.com/inward/record.url?scp=85026637991&partnerID=8YFLogxK
U2 - 10.1021/acs.est.7b00224
DO - 10.1021/acs.est.7b00224
M3 - Journal article
C2 - 28662579
SN - 0013-936X
VL - 51
SP - 8530
EP - 8536
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 15
ER -