Study of Mordenite ZSM-5 and NaY Zeolites,Containing Cr, Cs, Zn, Ni, Co, Li, Mn, to Control Hydrocarbon Cold-Start Emission

Authors: V. Golubeva, A. Korableva, O. Anischenko, A. Nemova, N. Yegorushina, L. Kustov, G. Kapustin, U.S.Rohatgi

Abstract:

The implementation of Super-Ultra Low Emission Vehicle standards requires more efficient exhaust gas purification. To increase the efficiency of exhaust gas purification, an the adsorbent capable of holding hydrocarbons up to 250-300 ОС should be developed. The possibility to design such adsorbents by modification of zeolites of mordenite type, ZSM-5 and NaY, using different metals cations has been studied. It has been shown that introducing Cr, Cs, Zn, Ni, Co, Li, Mn in zeolites results in modification of the toluene TPD and toluene sorption capacity. 5%LiZSM-5 zeolite exhibits the most attractive TPD curve, with toluene desorption temperature ranging from 250 to 350ОС. The sorption capacity of 5%Li-ZSM-5 is 0.4 mmol/g. NaY zeolite has the highest sorption capacity, up to 2 mmol/g, and holds toluene up to 350ОС, but at 120ОС toluene desorption starts, which is not desirable, since the adsorbent of cold start hydrocarbons should retain them until 250-300ОС. Therefore 5%LiZSM-5 zeolite was found to be the most promising to control the cold-start hydrocarbon emissions among the samples studied.

Keywords: Hydrocarbon emission control, adsorbents, zeolites, temperature-programmed desorption.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1072213

References:

[1] Absorbent-catalyst containing exhaust gas treatment device, Euro Patent 0737505, US Patent 5510086, General Motors Corp (US).
[2] Exhaust gas purification method and apparatus therefore, EU Patent EP0948987 (A1), ABE FUMIO, SUZUKI JUNICHI, OGAWA MASATO, Japan, 13.10.1999
[3] Cold start exhaust gas purifying catalyst, EU Patent EP1121981, Yamamoto, Shinji (1-44-15), Koyabe, Yokosuka-shi, Kanagawa-ken, JP), 10.01.2003
[4] Exhaust gas purification device in variable combination of absorbent and catalyst according to gas temperature, EU Patent EP0424966, Minami, Takashi (JP), Nagase, Toshimi (JP), 05.02.1991
[5] J.-H. Park, S. J. Park, H. A. Ahn, I.-S. Nama, G. K. Yeo, J. K. Kil, Y. K. Youn, "Promissing zeolite-type hydrocarbon trap catalyst by a knowledge-based combinatorial approach," Microporous and Mesoporous Materials, no 117, pp. 178-184, 2000.
[6] S.P. Elangovan, Masaru Ogura, Mark E. Davis, Tasuya Okubo, "A Promising Material for Use as Hydrocarbon Trap," The Journal of Physical Chemistry, B, vol. 108, no. 35, pp. 13059-13061, 2004.
[7] A. Iliyas, M.N. Zahedi-Niaki, M.Eić, S.Kaliaguine, "Control of hydrocarbon cold-start emissions: A search for potential adsorbents," Micropous and Mesoporous Materials, no.102, pp.171-177, 2007.