Modification of biochar derived from sawdust and its application in removal of tetracycline and copper from aqueous solution: Adsorption mechanism and modelling.

•Efficient tetracycline and Cu(II) sorption on iron and zinc doped sawdust biochar.•A mechanistic description of tetracycline and Cu(II) sorption using modelling.•The enhancement and competition of their interaction onto Fe/Zn-biochar was studied.•Give new insights on the development of biochar and advances its applications.