Removal of Elemental Mercury from Dry Methane Gas with Manganese Oxides
In this study, we sought to investigate the mercury
removal efficiency of manganese oxides from natural gas. The
fundamental studies on mercury removal with manganese oxides
sorbents were carried out in a laboratory scale fixed bed reactor at 30
°C with a mixture of methane (20%) and nitrogen gas laden with 4.8
ppb of elemental mercury. Manganese oxides with varying surface
area and crystalline phase were prepared by conventional precipitation
method in this study. The effects of surface area, crystallinity and
other metal oxides on mercury removal efficiency were investigated.
Effect of Ag impregnation on mercury removal efficiency was also
investigated. Ag supported on metal oxide such titania and zirconia as
reference materials were also used in this study for comparison. The
characteristics of mercury removal reaction with manganese oxide
was investigated using a temperature programmed desorption (TPD)
technique.
Manganese oxides showed very high Hg removal activity (about
73-93% Hg removal) for first time use. Surface area of the manganese
oxide samples decreased after heat-treatment and resulted in complete
loss of Hg removal ability for repeated use after Hg desorption in the
case of amorphous MnO2, and 75% loss of the initial Hg removal
activity for the crystalline MnO2. Mercury desorption efficiency of
crystalline MnO2 was very low (37%) for first time use and high (98%)
after second time use. Residual potassium content in MnO2 may have
some effect on the thermal stability of the adsorbed Hg species.
Desorption of Hg from manganese oxides occurs at much higher
temperatures (with a peak at 400 °C) than Ag/TiO2 or Ag/ZrO2.
Mercury may be captured on manganese oxides in the form of mercury
manganese oxide.
[1] W. W. Bodle, A. Attari, and R. Serauskas, "Consideration for Mercury in
LNG Operations," in sixth International Conference on Liquefied Natural
Gas, Kyoto, Japan, April 1980, Session 2, Paper 1.
[2] T. Y. Yan, "A Novel Process for Hg Removal from Gases," Industrial
Engineering Chemistry Research, vol 33, pp. 3010-3014, 1994.
[3] D. A. Biscan, R. Gebhard, and T. Matviya, "Impact of Process Conditions
on Mercury Removal from Natural Gas Using Activated Carbon," in 8th
Int. LNG Congr., Los Angeles, June 1986, Paper no. 1 II-5.
[4] M. J. Scott and J. J. Morgan, "Reaction at Oxide Surface. 2. Oxidation of
Se(IV) by synthetic Birnessite," Environ. Sci. Technol., vol. 30, pp.
1990-1996, 1996.
[5] A. Manceau and L. Charlet, "X-ray absorption spectroscopic study of the
sorption of Cr(III) at the oxide water interface : 1. molecular mechanism
of Cr(III) oxidation on Mn oxides," Journal of Colloid and Interface
Science, vol. 148, pp. 425-442, Feb. 1992.
[6] P. M. Huang, "Kinetics of redox reactions on manganese oxides and its
impact on environmental quality," in Soil Chemistry and Physics., pp.
191-230, 1991.
[7] W. Driehaus, R. Seith, and M. Jekel, "Oxidation of arsenate(III) with
manganese oxides in water treatment," Water Research, vol. 29, pp.
297-305, Jan. 1995.
[8] M. Ozaki, M. A. Uddin, and E. Sasaoka, "Temperature programmed
decomposition desorption of the mercury species over spent iron-based
sorbents for mercury removal from coal derived fuel gas," Fuel, vol. 87,
pp. 3610-3615, Dec. 2008.
[1] W. W. Bodle, A. Attari, and R. Serauskas, "Consideration for Mercury in
LNG Operations," in sixth International Conference on Liquefied Natural
Gas, Kyoto, Japan, April 1980, Session 2, Paper 1.
[2] T. Y. Yan, "A Novel Process for Hg Removal from Gases," Industrial
Engineering Chemistry Research, vol 33, pp. 3010-3014, 1994.
[3] D. A. Biscan, R. Gebhard, and T. Matviya, "Impact of Process Conditions
on Mercury Removal from Natural Gas Using Activated Carbon," in 8th
Int. LNG Congr., Los Angeles, June 1986, Paper no. 1 II-5.
[4] M. J. Scott and J. J. Morgan, "Reaction at Oxide Surface. 2. Oxidation of
Se(IV) by synthetic Birnessite," Environ. Sci. Technol., vol. 30, pp.
1990-1996, 1996.
[5] A. Manceau and L. Charlet, "X-ray absorption spectroscopic study of the
sorption of Cr(III) at the oxide water interface : 1. molecular mechanism
of Cr(III) oxidation on Mn oxides," Journal of Colloid and Interface
Science, vol. 148, pp. 425-442, Feb. 1992.
[6] P. M. Huang, "Kinetics of redox reactions on manganese oxides and its
impact on environmental quality," in Soil Chemistry and Physics., pp.
191-230, 1991.
[7] W. Driehaus, R. Seith, and M. Jekel, "Oxidation of arsenate(III) with
manganese oxides in water treatment," Water Research, vol. 29, pp.
297-305, Jan. 1995.
[8] M. Ozaki, M. A. Uddin, and E. Sasaoka, "Temperature programmed
decomposition desorption of the mercury species over spent iron-based
sorbents for mercury removal from coal derived fuel gas," Fuel, vol. 87,
pp. 3610-3615, Dec. 2008.
@article{"International Journal of Chemical, Materials and Biomolecular Sciences:62232", author = "Junya Takenami and Md. Azhar Uddin and Eiji Sasaoka and Yasushi Shioya and Tsuneyoshi Takase", title = "Removal of Elemental Mercury from Dry Methane Gas with Manganese Oxides", abstract = "In this study, we sought to investigate the mercury
removal efficiency of manganese oxides from natural gas. The
fundamental studies on mercury removal with manganese oxides
sorbents were carried out in a laboratory scale fixed bed reactor at 30
°C with a mixture of methane (20%) and nitrogen gas laden with 4.8
ppb of elemental mercury. Manganese oxides with varying surface
area and crystalline phase were prepared by conventional precipitation
method in this study. The effects of surface area, crystallinity and
other metal oxides on mercury removal efficiency were investigated.
Effect of Ag impregnation on mercury removal efficiency was also
investigated. Ag supported on metal oxide such titania and zirconia as
reference materials were also used in this study for comparison. The
characteristics of mercury removal reaction with manganese oxide
was investigated using a temperature programmed desorption (TPD)
technique.
Manganese oxides showed very high Hg removal activity (about
73-93% Hg removal) for first time use. Surface area of the manganese
oxide samples decreased after heat-treatment and resulted in complete
loss of Hg removal ability for repeated use after Hg desorption in the
case of amorphous MnO2, and 75% loss of the initial Hg removal
activity for the crystalline MnO2. Mercury desorption efficiency of
crystalline MnO2 was very low (37%) for first time use and high (98%)
after second time use. Residual potassium content in MnO2 may have
some effect on the thermal stability of the adsorbed Hg species.
Desorption of Hg from manganese oxides occurs at much higher
temperatures (with a peak at 400 °C) than Ag/TiO2 or Ag/ZrO2.
Mercury may be captured on manganese oxides in the form of mercury
manganese oxide.", keywords = "Mercury removal, Metal and metal oxide sorbents,
Methane, Natural gas.", volume = "3", number = "8", pages = "423-5", }