Comprehensive insights into the influences of acid-base properties of chemical pretreatment reagents on biomass pyrolysis behavior and wood vinegar properties

•The acid-base properties of chemical reagents exhibited obvious influence on pyrolysis behavior and WV properties.•Chemical pretreatments promoted the pyrolysis process, and acids showed the more obvious effects than alkalis.•Chemical pretreatments increased organic content of WV.•Chemical pretreatments enhanced the relative content of phenols in WV with different levels.•The relative content of acids increased by inorganic acids pretreated, but reduced by alkalis and organic acids pretreated.