Comparative study on thermal pyrolysis of buckwheat and wheat straws by using TGA-FTIR and Py-GC/MS methods

•Pyrolysis behavior of buckwheat and wheat straws was compared.•Buckwheat straw produced larger amount of non-condensable gases than wheat straw.•Wheat straw showed more furan derivatives, ketones, and aldehydes.•Temperature play more significant role than heating rate from 60 to 100 °C/min.

The pyrolysis characteristics of buckwheat and wheat straws were investigated using TGA-FTIR and Py-GC/MS methods in order to determine the influence of chemical composition on the evolution profile and relative yield of the volatile compounds. The influence of pyrolysis parameters such as temperature and heating rate for the relative yield of product distribution was studied. Intermediate pyrolysis of wheat straw produced the larger amount of ketones, aldehydes, and furan derivatives whereas a larger amount of non-condensable gases, phenols and aromatics were generated from pyrolysis of buckwheat straw. The heating rate in the range from 60 to 100 °C/min has an obvious effect on the formation of non- condensable gases, organic acids, compounds containing hydroxyl groups, diacetyl and furan derivatives. The pyrolysis temperature in the range from 250 to 700 °C plays a significant role on the product distribution from buckwheat and wheat straws. Unlike of intermediate pyrolysis, fast pyrolysis of wheat straw produced the larger amount of phenolic compounds than from buckwheat straw.