Effect of catalytic vapour cracking on fuel properties and composition of castor seed pyrolytic oil

•Catalytic vapour cracking was carried out on castor seed using Kaolin, CaO and ZnO.•Yield of pyrolytic oil varied with catalyst type and its amount of loading.•Fuel properties of castor seed thermal and catalytic pyrolytic oil were compared.•Cracking enhanced the fuel properties of oil including the calorific value.•Catalysts reduced the viscosity and altered the pH of pyrolytic oil.

In this work, catalytic upgrading was carried out to enhance the yield and quality of castor seed pyrolytic oil. The influence of catalytic vapour cracking of castor seed was performed over Kaolin, CaO and ZnO catalysts at various weight percentage of loading. This study confirmed that the yield varied with catalyst type and its amount of loading. The maximum pyrolysis yield of oil was obtained about 66.4 wt.%, 64.9 wt.% and 65.8 wt.% at 15 wt.% CaO and Kaolin and 10 wt.% ZnO respectively. The effect of catalyst on fuel properties were studied at that catalyst loading where the yield of pyrolytic liquid was higher. The fuel properties of castor seed thermal and catalytic pyrolytic oil were compared. The cracking of castor seed pyrolytic vapour over the bed of catalysts proved to enhance the fuel properties of pyrolytic oil for all catalysts. In comparison with ZnO, CaO and Kaolin found to have significant effect on enhancing the fuel properties in terms of viscosity, pH, calorific value and pour point. It was observed that in catalytic pyrolytic oil the number of acidic groups significantly reduced as they got converted to esters compared to thermal pyrolytic oil. The increase in the formation of nitriles and aromatics content in the catalytic pyrolytic oil was also noticed which were comparatively less in the thermal pyrolytic oil.