浸渍活性炭性能和微观结构老化效应研究

Abstract

Abstract: In order to study the properties and structure changes of impregnated activated carbon caused by aging, the adsorption efficiency, key physical properties, microstructure and thermal stability of impregnated activated carbon aging through in-place application and natural aging in the same batch were analyzed. It was found that that the performance indicators change of impregnated activated carbon was not significant after natural aging for 54 months. While for the impregnated activated carbon aging in-place, its efficiency for adsorbing radioactive methyl iodine dropped to less than 60%, the CCl₄ adsorption rate dropped significantly from the initial nearly 60% to 15%, pH value decreased from 9.7 to 7.2, the iodine adsorption value fell to three-quarters that of new impregnated activated carbon, which is consistent with the declining trend of iodine removal efficiency. SEM and N₂ adsorption tests showed that the microscopic pore structure of the activated carbon samples after aging in-place changed significantly, the pores were blocked and worn seriously, the specific surface area decreased, and the pore width increased. Thermogravimetry (TG) test showed that the weight loss of impregnated activated carbon aging in-place was about 10% at 200-500 ℃. These changes in physical and chemical properties and structure are the main reasons for the aging and declining of iodine-removing properties of impregnated activated carbon.

Key words: impregnated activated carbon, aging, physical and chemical property, microstructure, adsorption efficiency

CLC Number:

TL941

WANG Kunjun, CHANG Sen, WANG Longjiang, LI Yongguo, HOU Jianrong, QIU Dangui. Study on properties and structure changes of impregnated activated carbon induced by aging[J].RADIATION PROTECTION, 2021, 41(4): 351-358.

References

[1] 核工业标准化研究所.核空气和气体处理规范通风、空调与空气净化第11部分:碘吸附器(Ⅰ型):NB/T 20039.11—2011 [S]. 北京:原子能出版社, 2011.
[2] Emma A, Diana B, Mark R StJ. Affinity of charcoals for different forms of radioactive organic iodine[J]. Nuclear Engineering and Design, 2018, 328: 228-240.
[3] ZHOU J, HAO S, GAO L, et al. Study on adsorption performance of coal based activated carbon to radioactive iodine and stable iodine[J]. Annals of Nuclear Energy, 2014, 72:237-241.
[4] Nandanwar S U, Coldsnow K, Utgikar V, et al. Capture of harmful radioactive contaminants from off-gas stream using porous solid sorbents for clean environment—A review[J]. Chemical Engineering Journal, 2016, 306:369-381.
[5] 王坤俊, 王龙江, 韩丽红, 等. 核空气净化用浸渍活性炭的中毒老化效应及影响因素分析[J]. 化工新型材料, 2018, 46(9):190-194.
WANG Kunjun, WANG Longjiang, HAN Lihong, et al. Analysis of effects and influence factors on poisoning and aging of impregnated activated carbon for nuclear air cleaning[J]. New Chemical Materials, 2018, 46(9):190-194.
[6] Wren J C, Moore C J, Rasmussen M T. Methyl iodide trapping efficiency of aged charcoal samples from bruce—A emergency filtered air discharge systems[J]. Nuclear Technology, 1999, 125(1):28-39.
[7] Winegardner W K. Phase I aging assessment of nuclear air-treatment system high efficiency particulate air and adsorbers[J]. Nuclear Engineering and Design, 1996, 163 (3):315-322.
[8] Wren J C, Moore C J. The effect of weathering on charcoal filter performance: I. The adsorption and desorption behavior of contaminants[J]. Nuclear Technology, 1991, 94(2):242-251.
[9] Deuber H, Gerlach K, Kaempffer R. Investigations on the aging of activated carbons in the exhaust air of a pressurized water reactor[J]. Nuclear Technology, 1985, 70(2):161-166.
[10] González-García C M, González J F, Román S. Removal efficiency of radioactive methyl iodide on TEDA-impregnated activated carbons[J]. Fuel Processing Technology, 2011, 92 (2):247-252.
[11] 核工业标准化研究所. 核级活性炭去除甲基碘性能试验方法:EJ/T 20056—2014[S]. 北京:原子能出版社, 2014.
[12] ASTM. Standard test method for nuclear-grade activated carbon:ASTM D 3803—1998[S]. Philadelphia, PA: ASTM International, 1998.
[13] ASTM. Standard test method for carbon tetrachloride activity of activated carbon:ASTM D 3467—2004[S]. Philadelphia, PA: ASTM International, 2004.
[14] ASTM. Standard test method for ph of activated carbon:ASTM D3838—2011[S]. Philadelphia, PA: ASTM International, 2011.
[15] ASTM. Standard test method for ball-pan hardness of activated carbon:ASTM D 3802—1999[S]. Philadelphia, PA: ASTM International, 1999.
[16] ASTM. Standard test method for determination of iodine number of activated carbon:ASTM D 4607—1994[S]. Philadelphia, PA: ASTM International, 1994.
[17] ASTM. Standard test method for ignition temperature of g ranular activated carbon:ASTM D 3466—2006[S]. Philadelphia, PA: ASTM International, 2006.
[18] ASTM. Standard test method for total ash content of activated carbon:ASTM D 2866—2011[S]. Philadelphia, PA: ASTM International, 2011.

Study on properties and structure changes of impregnated activated carbon induced by aging

PDF (PC)

Like

Knowledge

Abstract

Cite this article

share this article

References

Related Articles 2

Metrics

Comments

Recommended 10

[1]	YAO Zhen, ZHAO Minyan, LIU Yulong. Application of infrared imaging in radiation protection and other medical fields [J]. RADIATION PROTECTION, 2020, 40(1): 78-83.
[2]	LI Yongguo, WANG Longjiang, SHI Yingxia, WANG Kunjun, LV Yang, ZHANG Jirong, QIU Dangui, HIU Jianrong, LIU Qun, XU Yangyang. Performance research and selection of activated carbons used in delay bed of nuclear power plants [J]. RADIATION PROTECTION, 2018, 38(2): 148-154.