Boreskov Institute of Catalysis of the Siberian Branch of Russian ...

PP-II-1For investigation, we used non-modified fiberglass material and that modified by aluminasulfate. The numerical analysis of the response curves showed that the H/D-exchange obeysthe type II mechanism, i.e. it proceeds on the single sites. The modification of the catalystresults in multifold increase in the integral exchange rate which is due to the appearance ofadditional acid sites. Part of them is located in the subsurface layers of fibers. Besides, thenew type of sites is appeared; these sites are located at the external surface of fibers and donot exist in non-modified sample. On the basis of the numerical simulation of H/D-exchangedynamics, we revealed the difference in the H/D-exchange rates with the different acid sites inthe subsurface layers of fibers, to estimate the concentration of these sites, and also todetermine the overall amount of the exchangeable hydrogen atoms in the catalyst bulk. Whencompared the H/D-exchange rates over the fiberglass materials with the results obtained overthe model samples (zeolite HZSM-5 and aerosil), we estimated the BAS strength of fiberglassmaterials in proton affinity scale. It was shown that the strength of Brønsted acid sites offiberglass materials is comparable to that of zeolite.The developed technique could be used for kinetic investigation of any catalytic processestaking place on fiberglass materials.References:1. L. Kiwi-Minsker, I. Yuranov, V. Holler, A. Renken // Chem. Eng. Sci., 54 (1999) 4785.2. L.G. Simonova, V.V. Barelko, O.B. Lapina, E.A. Paukshtis, V.V. Terskikh, V.I. Zaikovskii,B.S. Bal’zhinimaev // Kinet. Catal., 42 (2001) 693.3. B.S. Bal’zhinimaev, L.G. Simonova, V.V. Barelko, A.V. Toktarev, V.I. Zaikovskii, V.A. Chumachenko //Chem. Eng. J., 91 (2003) 175.274