abstract |
There is provided a process for preparing a catalyst for reforming, particularly steam reforming of hydrocarbons. The process consists fundamentally in mixing intimately a solution of sodium or potassium aluminate, possibly containing excess of base (preferably sodium or potassium hydroxide, respectively) with either a solution of a nickel salt and a magnesium salt, or a solution of a nickel salt containing finely dispersed therein reactive magnesium oxide. The mixing results in coprecipitation of a fine sludge containing intimately mixed aluminum hydroxide, nickel hydroxide and either magnesium hydroxide (if a magnesium salt is used) or magnesium oxide. The sludge also contains a sodium or potassium salt which is removed by washing. The washed sludge is dried and dehydrated at 300-750* C., whereby an intimate mixture of oxides of magnesium, aluminium and nickel is formed. This mixture is pelletted in conventional manner and the pellets or bodies calcined at a temperature of 850-1100* C. The calcination involves conversion of alumina and part of the magnesia into spinel, whereas remaining magnesia during reforming acts as ''''promoter,'''' i.a. to counteract carbon deposition. The precursor thus obtained contains NiO and can be reduced, preferably by hydrogen, and is thereafter suitable as catalyst containing elemental Ni for reforming reactions. |