Effect of zinc-containing nanopowders on the catalytic intermediate pyrolysis of buckwheat straw by using TGA-FTIR method

•Zinc-containing nanopowders were using for catalytic pyrolysis of buckwheat straw.•ZnAl2O4 and 2 %Ag/ZnO promotes the release of non-condensable gases.•The highest bio-oil yield (53 wt%) is obtaining with the addition of ZnWO4.•2 % Ag/ZnO promotes the production of monocyclic aromatic hydrocarbons.•ZnO significantly reduced the formation of olefins. Pyrolysis of buckwheat straw with or without catalysts was investigated using the TGA-FTIR method to determine the influence of zinc-containing nanopowders (ZnO, 1.5 % Er2O3/ZnO, 2 % Ag/ZnO, ZnWO4, ZnAl2O4, and Mn-Zn ferrite) on the distribution of pyrolysis products. The presence of ZnWO4, ZnAl2O4, and Mn-Zn ferrite exhibited the highest bio-oil yields, whereas the highest non-condensable gas yield and the lowest bio-oil yield was obtained with the addition of 2 % Ag/ZnO catalyst. According to the obtained results, ZnWO4 promoted the production of oxygen-containing compounds while the presence of 2 % Ag/ZnO presented the highest amounts of hydrocarbons. The 2 % Ag/ZnO shows a greater effect on the production of monocyclic aromatic hydrocarbons but ZnWO4 inhibits the formation of these compounds. The amounts of olefins slightly increased in the presence of ZnWO4 while the ZnO significantly reduced the formation of olefins.