## 1 Introduction
They offer, apart from a high surface area, good hydrothermal stability, flexible chemical composition and unique microporous structure. Even though their considerable versatility, few groups focused on them for CO\({}_{2}\) methanation reaction. Recently, [PERSON] et al. [18] reviewed the studies on this field showing that parameters such as the preparation conditions [19; 20; 21; 22; 23], framework type [15; 20; 24], Si/Al ratio [24; 25] or compensating cation [26] strongly affects the catalytic properties of the final material. The increase of calcination temperature is reported to favor the formation of sintered NiO nanoparticles in more internal locations of the zeolite. This migration of Ni species generally leads to a shift to higher temperature in TPR profiles [19; 20]. Regarding reduction, the selection of a high temperature results in a greater amount of reduced Ni, but also produces nanoparticle sintering, reducing the active surface [19]. Another parameter affecting the size of the nanoparticles in zeolite is the metal precursor. [PERSON] et al. [20] found that the use of citrate and acetate yields smaller NiO particle size in comparison with nitrate. Furthermore, the Ni loading [23], the method used to incorporate the elements of the catalyst [21; 22; 23] and the order of incorporation of these elements have been also studied [21; 22]. Zeolites that are used as support for methanation catalysts are normally exchanged with sodium. [PERSON] et al. [15] reported that the exchange of the protons by sodium in zeolites Y and Beta results in an enhancement of both Ni reducibility and weak CO\({}_{2}\) adsorption sites. However, in a previous study no influence on Ni reducibility was observed by the addition of different cations to ultrastable zeolite Y (USY) [26]. Also in this study, the following order was established for the enhancement of catalytic activity using Ni catalysts supported on cation exchanged zeolites: Cs\({}^{+}\) \(>\) Na\({}^{+}\)\(>\) Li\({}^{+}\)\(>\) K\({}^{+}\)\(>\) H\({}^{+}\) and Mg\({}^{2+}\)\(>\) Ca\({}^{2+}\)\(>\) Ba\({}^{2+}\)[26]. Independently of the compensating cation (H\({}^{+}\), Na\({}^{+}\), Cs\({}^{+}\)), an improvement of the catalytic performance was achieved increasing the Si/Al ratio of USY zeolite [25]. This trend was against what was expected, attending to the basicity of the materials, as samples with high Al content (lower Si/Al ratio) present higher CO\({}_{2}\) adsorption capacity. However, it can be ascribed to the more hydrophobic character of the catalysts supported on zeolites of a higher Si/Al ratio [25]. By this time, different zeolite structures have been considered as supports for CO\({}_{2}\) methanation catalysts: USY [15; 23], Beta [15; 24], ZSM-5 [24], 13X [20] and 5A [20]. The type of zeolite used is reported to have an influence on the hydrophobicity of the final catalyst [24] as well as on the location and reducibility of Ni nanoparticles [15; 20]. As far as we know, the particular structure of delaminated zeolites has not been considered for CO\({}_{2}\) methanation reaction. This kind of material provides a very high external surface area, which increases the accessibility to the active sites maintaining the properties of the zeolite and making these materials a promising option to prepare highly dispersed metal catalysts. Therefore, the aim of this work is to gain insight into the effect of the structure of the zeolite used as support and its Si/Al ratio on the catalytic performance for CO\({}_{2}\) methanation reaction. For this purpose, four zeolitic materials were used: two ITQ-2 and two ZSM-5, differing the zeolites of each type in the Al content, to prepare catalysts with 5 wt.% of Ni. These samples have been characterized and tested in CO\({}_{2}\) methanation reaction.