Catalytic upgrading of pyrolysis vapors from Jatropha wastes using alumina, zirconia and titania based catalysts

• Successfully upgrade pyrolysis vapors of Jatropha wastes by metal/ceramic supporter.
• Hydrocarbon selectivity was TiO(T2) > Al2O3 > CA > NiCA > RuCA.
• Al2O3 and T2 based catalysts yield high hydrocarbons and less oxygenates.
• Aliphatics (C5–C11) was the main hydrocarbons obtained by of Al2O3 based catalysts.

The objective of this study was to catalytically upgrade bio-oil from organic vapors of Jatropha wastes using Py–GC/MS. Catalytic testing included Al2O3, ZrO2, TiO2 (rutile, T1) and TiO2 (anatase, T2) supporter catalysts modified with transition metals (Pd, Ru or Ni) by impregnation method. In non-catalytic runs, the main vapor products were fatty acids (60.74%). With the presence of Al2O3 based catalysts, carboxylic acids were obviously reduced to 0.76–19.61% while hydrocarbons were the main products (42.00–64.06%). Comparing among four supporters, total hydrocarbon yields increased with presence of all catalysts. Higher yields were obtained by T2 > Al2O3 > CA > NiCA > RuCA catalysts. Al2O3 and T2 supports were the most effective for increased hydrocarbons while decreased oxygenated compounds (15%) which is one of the primary aims of this study. The result indicating that high surface area resulted in better catalytic activity but also adversely promoted N-compounds. Therefore these catalysts can be applied to improve properties of pyrolytic products.