Impacts of catalyst, inorganic and organic corrodants on corrosion under batch-mode catalytic biomass hydrothermal liquefaction conversion

Catalytic hydrothermal liquefaction (CHTL) is used to convert wet biomass for highly promising carbon conversion efficiency. This study investigated three major environmental factors, including catalyst, inorganic corrodants and organic acid on the corrosion of two candidate reactor steels (SS310 and P91) using autoclave methodology and advanced characterization techniques. The addition of 0.5 M K2CO3 resulted in a remarkable increase in corrosion rates and significantly changed the corrosion layers formed. The acetic acid generated from CHTL also noticeably enhanced corrosion while the presence of Cl- and S2- only had marginable influence. SS310 exhibited much better performance than P91 under the CHTL conditions. •Corrosion of constructional steels was investigated in catalytic hydrothermal liquefaction.•SS310 and P91 steel has been studied in three distinct CHTL environments.•The presence of catalyst K2CO3 led to noticeable increase in steels’ corrosion rates.•Existence of Cl-, S2-, and acetic acid changed the corrosion kinetics and mechanism.