Simulating study of atmospheric corrosion of steels in a coastal industrial zone: Effect of SO32− on the formation of β-FeOOH rust particles synthesized from FeCl3 solutions

•Artificial β-FeOOH rust particles were prepared in aqueous FeCl3 solutions containing Na2SO3.•Adding SO42− suppressed the formation and crystallization of β-FeOOH rust particles.•Added SO32− broke the coordination of Cl− and OH− to Fe3+ in Fe3+-complex and reduced the Fe3+ to Fe2+.•In coastal industrial atmosphere, SO32− formed from SOX would inhibit the formation of β-FeOOH rust.