CALCULATION OF NITROGEN HEAT ADSORPTION ON VARIOUS CATALYSTS USING BET-CONSTANT (BET-C) DATA

Triyono Triyono, Wega Trisunaryanti, Oberlin Sidjabat

Abstract


BET-C (Brunauer-Emmett-Teller-Constant) was used to calculate the heat of adsorption (ΔHads) of nitrogen gas on the various catalysts. The well-known Brunauer–Emmett– Teller (B.E.T.) equation is used primarily to determine the surface area from the physical adsorption of a gas on a solid surface. Surface area of catalysts was determined by using surface area analyzer (NOVA 1000). The BET-C included in the data is usually neglected or is not taken into account. However, by using the basic principles of the adsorption theory fitted with the functions based on the BET adsorption model, the important data of BET-C can be shown in this study. The value of the ΔHads (N2 ) for zeolite, H-zeolite, Pt/zeolite, Pt-Pd/zeolite, and Pt-Ce/zeolite calculated from the equation derived from BET-C are -6.43, -6.52, -8.78, -8.69, -9.71 and -9.52 kJ/mol, respectively.


Keywords


BET, Adsorption, Catalyst, Surface Area

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References


Paserba, K. R., Gellman, A. J., 2001, Kinetics and energetics of oligomer desorption from surfaces. Phys. Rev. Lett. 86, 19, 4338-4341.

Ammann, M., Pöschl, U and Rudich, Y., 2003, Effects of reversible adsorption and LangmuirHinshelwood surface reactions on gas uptake by atmospheric particles, J. Phys. Chem. 5, 351-356.

Tielens, F and Geerlings, P., 2002, Adsorption energy surfaces in faujasite type zeolites Adsorption energy surfaces in faujasite type zeolites, Chem. Phys. Lett. 354, 474-482.

Bishop, A. .R.; Girolami, G. S.; Nuzzo, R. G. 2000,Structural models and thermal desorption energetics for multilayer assemblies of the n-alkanes on Pt(111), J. Phys. Chem. B 104 , 4, 754- 763.

Bartels, T., Eichler, B., Zimmermann, P., Gäggeler, H., Ammann, M., 2002, The adsorption enthalpy of nitrogen oxides on crystalline ice, Atm. Chem. and Phys. 2, 235-247.

Orita, H., Uchida. K and Itoh.N., 2004, A volcano-type relationship between the adsorption energy of thiophene on promoted MoS2 clustermodel catalysts and the experimental HDS activity: ab initio density functional study, Appl. Catal. A: General, 258, 1, 115-120.

Hsieh,C.T and Chen, J.M., 2002, Adsorption energy distribution model for VOCs onto activated carbons, J. Coll. Interface Sci. 255, 2, 248-253

Paserba, K.R; Gellman, A. J., 2001, Effects of conformational isomerism on the desorption kinetics of n-alkanes from graphite. J. Chem. Phys. 115, 14, 6737-6751. ¬




DOI: https://doi.org/10.29017/SCOG.31.3.1012

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