The effect of alkali metals on the surface area of iron catalyst for ammonia synthesis

• Autorzy: Jasińska I. , Moszyński D. , Arabczyk W. , Kaleńczuk R.
• Języki publikacji: EN

Abstrakty

EN

The surface area of the iron catalyst for ammonia synthesis impregnated with lithium, sodium, potassium and cesium was examined. The concentration of the respective element (expressed in mole fraction) in the bulk of the catalyst sample was varied from near zero to 1.5-10~3. The increase in the concentration of the promoter led to the decrease of the surface area of the catalyst regardless of the element present in the bulk. The exponential equation has been proposed to describe this dependence. The empirical factor AM o from the mentioned equation, which differs from element to element, was correlated with the difference between the formation enthalpy of A12O3 and the respective alkali metal oxide. The observed dependence obeys a linear law.

Słowa kluczowe

EN

alkali metals; surface area; iron catalyst; ammonia synthesis

PL

katalizator żelazowy; synteza amoniaku; powierzchnia właściwa; metale alkaliczne

• Wydawca: West Pomeranian University of Technology. Publishing House
• Czasopismo: Polish Journal of Chemical Technology
• Rocznik: 2003
• Tom: Vol. 5, nr 4
• Strony: 70--72
• Opis fizyczny: Bibliogr. 22 poz., rys., tab.

Twórcy

autor

Jasińska I.

autor

Moszyński D.

autor

Arabczyk W.

autor

Kaleńczuk R.

• Technical University of Szczecin, Institute of Chemical and Environment Engeneering, ul. Pułaskiego 10, 70-322 Szczecin, Poland,,

Bibliografia

• (1) Dry, M.E., Du Plessis, J.A.K., Leuteritz, G.M., The influence of structural promoters on the surface properties of reduced magnetite catalysts, J.Catal., 1966, 6, 194.
• (2) Emmett, P.H., Brunauer, S., Accumulation of alkali promoters on surface of iron synthetic catalysts, J. Am.Chem.Soc., 1937, 59,310.
• (3) Emmett, P.H., Brunauer, S., Chemisorptions of gases on iron synthetic ammonia catalysts, J. Am.Chem. Soc., 1940, 62, 1732.
• (4) Krabetz, R., Peters, C., Function of the activators in technical ammonia catalyst, Angew.Chem., 1965, 77, 333.
• (5) Solbakken, V., Solbakken, A., Emmett, P.H., The exchange of H2180 with the oxides of promoters on the surface of iron catalysts J.Catal., 1969,15,90.
• (6) Ertl, G., Prigge, D., Schlögl, R., Weiss, M., Surface characterization of ammonia synthesis catalysts, J. Catal., 1983, 79, 359.
• (7) Schlögl, R., Preparation and activation of the technical ammonia synthesis catalyst, In Catalytic Ammonia Synthesis - Fundamental and Practice; Jennings, J.R. Ed., Plenum Press, New York, 1991; Chapter 2.
• (8) Silverman, D.C., Boudart, M., Surface composition of promoted iron catalysts J. Catal., 1982, 77, 208.
• (9) Chudinov, M.G., Perov, W.M., Ksenzenko, W.I., Alekseev, A.M., Study of the surface composition of industrial ammonia- catalyst S.A.-I and model system based on iron by XPS, Chim. Prom., 1986, 2, 92.
• (10) Van Ommen, J.G., Bolink, W.J., Prasad, J., Mars, P., The nature of the potassium compound acting as a promoter in iron alumina catalysts for ammonia synthesis J. Catal., 38, 120 (1975).
• (11) Ertl, G., Primary steps in catalystic synthesis of ammonia, J. Vac. Sci. Technol., 1983, AI(2), 1247.
• (12) Klisurski, D., Mitov, L, Tomov, T., A study of the preparation and properties of precipitated iron catalysts for ammonia synthesis, Stud. Surf. Sci. Catal., 1983, 16, 421.
• (13) Ozaki, A., Aika, K., Morikawa, Y., Proc. 5th Intern. Congr.Catal. The role of potassium in ammonia synthesis cataIysts, 1972, 2, 1251.
• (14) Bosch, H., van Ommen, J.G., Gellings, P.J., On the role of alkali metals in ammonia synthesis, Appl. Catal., 1985, 18, 405.
• (15) Kuzniecov, L.D., Dmitrienko, L.M., Rabina, P.O., Sokolinskij, U.A., Syntez Ammiaka, Chimija, Moskwa, 1982, 113.
• (16) Arabczyk, W., Narkiewicz, U., Moszyński, D., Double- layer model of the fused iron catalyst for ammonia synthesis, Langmuir, 1999, 15(18),5785.
• (17) Arabczyk W., Narkiewicz, U., Kałucki, K., Model of active surface of iron catalyst for ammonia synthesis, Vacuum, 1994, 45(21 3), 267.
• (18) Lendzion-Bieluń, Z., Arabczyk W., Method for determination of the chemical composition of phases of the iron catalyst precursor for the ammonia synthesis Appl. Catal., 2001, 207 (1-2), 37 .
• (19) Kałucki, K., Arabczyk W., Narkiewicz U., Śpiewak Z., Przemysłowy katalizator syntezy amoniaku o zwiększonej odporności termicznej, Przem. Chem., 1994, 73/5, 174.
• (20) Nielsen, A., An Investigation on Promoted Iron Catalyst for The Synthesis of Ammonia, Jul. Gjellerups Forlag, Copenhagen, 1968, 122.
• (21) Kowalczyk Z., Etfect of potassium on the high pressure kinetics of ammonia synthesis over fused iron catalyst, Catal. Lett., 1996, 37, 173.
• (22) Kowalczyk Z., Jodzis S., Środa J., Influence of aluminium and potassium on the activity and texture of fused iron catalyst for ammonia synthesis, Appl. Catal., 1982, A87, 1..