Hydrogen generation by ammonia decomposition using Co/MgO–La2O3 catalyst: Influence of support calcination atmosphere

• Thermal treatment of support in nitrogen atmosphere leads to most active catalyst (5CMLa–N2) for ammonia decomposition.
• The interaction of Mg, La and Co varied with support thermal treatment in different atmospheres (N2, Air, Vaccum).
• The surface metal concentration was increased in 5CMLa–N2catalysts.
• The moderate basic site density was increased in 5CMLa–N2catalysts compared with other catalysts.

Performing calcinations of the support in different atmospheres is a vital precondition for preparation of active cobalt supported on MgO–La2O3 catalyst for ammonia decomposition. This work studied the influence of support calcination conditions on basic properties, morphology and catalytic performance. The catalytic performance was evaluated in the temperature range of 300–550 °C at atmospheric pressure. The XPS results showed the surface metal concentration was increased in 5 wt% Co supported on MgLa mixed oxide catalyst (5CMLa–N2) whose support was calcined in N2 atmosphere. The TPR measurements showed strong metal support interaction in 5CMLa–N2 catalyst. From the SEM results the formation of MgLa mixed oxide was increased in 5CMLa–N2 catalyst. The moderate basic site density determined by CO2 TPD results was increased in 5CMLa–N2 catalysts compared with other catalysts. These outcomes are might be one of the reasons in enhancing activity in 5CMLa–N2 catalysts compared to other catalysts. Hence support calcinations under N2 being the best choice, was the one of the parameters that influenced on catalytic properties of the cobalt on MgO–La2O3 system, for ammonia decomposition.

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