Soybean soapstock(SS)is one of the main solid wastes produced in the refinery of edible oil processing.In this study,the co-pyrolysis of SS with iron slag(IS)and aluminum scrap(AS)was carried out in a tubular furnace.The gas,liquid and solid products were characterized and the char yield decreased with increas-ing IS/AS ratio.IS and AS can improve the gas yield,and when the ratio of SS/IS was 1:0.25,the total pyrol-ysis gas and hydrogen contents were significantly increased.The content of oxygen compounds in pyrolysis oil decreased during co-pyrolysis,while AS promoted the content of polycyclic aromatic hydro-carbons in pyrolysis oil.The co-pyrolysis reaction can be divided into four stages,the mass loss rate reaches the maximum at the third stage(390-575℃).The molar ratio of H/C was lower for pyrolysis,indicating good stability of pyrolysis char owing to the high degree of carbonization and aromaticity.The possible co-pyrolysis reaction mechanism was explored.