Nickel-containing catalysts are applied on a large scale in chemical industry in many reactions of organic synthesis including hydrogenation of nitro compounds, alkenes, alkines, aromatic compounds, carbonyl compounds, nitriles, as well as in ammonolysis of alcohols and methanation reactions.
The NiF2-MgF2 binary fluorides used in our research were prepared by the precipitation from a solution of a mixture of nickel nitrate (V) and magnesium nitrate(V) with an aqueous solution of ammonium fluoride. The obtained precipitate of binary fluorides was reduced with hydrogen atmosphere at 500°C.
The catalysts were tested using TPR-H2, XRD, BET methods. After reduction at 500°C, these catalysts have metallic nickel, large surface area and mezopores. The obtained catalysts have been studied in the CO2 methanation reaction. All binary fluorides are active and show high reaction conversion. The highest conversion is for the catalyst containing 85 mol% NiF2 and 15 mol% MgF2. It also has high reaction selectivity to methane.
The way of nickel catalyst synthesis developed in this study is very simple, because it does not require the introduction of a support and enables a precise control of nickel metal content.