[en] This work investigated the intrinsic properties and performances of Ni/γ-Al2O3-SiO2 modified with different silicon precursors for the steam reforming of toluene in biomass gasifier exit conditions (8000 ppmv of toluene, 650 °C). Samples were synthesized by an aqueous sol-gel process in presence of aluminum nitrate, nickel nitrate and the use of either tetramethoxysilane (TMOS, Si-(OCH3)4) or tetraethoxysilane (TEOS, Si-(OC2H5)4) in order to understand the influence of the reactivity of the silicon precursor. Furthermore, the use of N-[3-(trimethoxysilyl)propyl]ethylenediamine (EDAS, (OCH3)3-Si-(CH2)3-NH-(CH2)2-NH2) is also investigated in order to understand the influence of a silicon precursor containing an ethylenediamine group, able to complex Ni2+ ions.
By the chelation of Ni2+ ions by ethylenediamine groups during the synthesis, Ni/γ-Al2O3-SiO2 samples modified with EDAS showed higher dispersion of the metallic Ni nanoparticles and the higher resistance against the sintering of Ni particles. This was also attributed to the high microporous volume and the narrow mesoporous distribution of the support, which could also prevent the migration of the metallic Ni nanoparticles.
The catalytic tests revealed that the reactivity of the silicon precursor played a major role on the conversion of toluene. For alumina supports modified with a silicon precursor with a low reactivity such as TEOS, the low integration of the Si atoms inside the bulk alumina lead to a slightly higher catalytic activity, but also to a high formation of structured carbon. The opposite effect was observed for the samples modified with a highly reactive silicon precursor, such as TMOS or EDAS, which showed a slightly lower catalytic activity, but a higher resistance against coking compared to pure Ni/γ-Al2O3 catalysts.
Disciplines :
Materials science & engineering Chemical engineering
Author, co-author :
Claude, Vincent
Mahy, Julien ; Université de Liège - ULiège > Department of Chemical Engineering > Department of Chemical Engineering
Geens, Jérémy ; Université de Liège - ULiège > Department of Chemical Engineering > Department of Chemical Engineering
Courson, Claire
Lambert, Stéphanie ; Université de Liège - ULiège > Department of Chemical Engineering > Department of Chemical Engineering
Language :
English
Title :
Synthesis of Ni/γ-Al2O3-SiO2 catalysts with different silicon precursors for the steam toluene reforming
Mahy, J.G., Claude, V., Sacco, L., Lambert, S.D., J. Sol. Gel Sci. Technol. 81 (2017), 59–68.
Bodson, C.J., Lambert, S.D., Alié, C., Cattoën, X., Pirard, J.-P., Bied, C., Wong Chi Man, M., Heinrichs, B., Microporous Mesoporous Mater. 134 (2010), 157–164.
Paoletti, P., Pure Appl. Chem. 56 (1984), 491–522.
Jiang, H., Sun, X., Du, Y., Chen, R., Xing, W., Catalytic activity of palladium nanoparticles immobilized on an amino-functionalized ceramic membrane support. Chin. J. Catal. 35 (2014), 1990–1996.
Rahmanpour, O., Shariati, A., Reza, M., Nikou, K., Int. J. Chem. Eng. Appl. 3 (2012), 2–5.
Lecloux, A.J., Anderson, J.R., Boudart, M., (eds.)Texture of Catalysts, Catalysis: Science and Technology, vol. 2, 1981, Springer, Berlin, 171.