Electric arc furnace dust (EAFD) is a high-volume steel manufacturing byproduct with currently limited value-added applications. EAFD contains metal oxides that can react with H2S to form stable sulfides. Hence, the valorization potential of EAFD as an adsorbent material for syngas H2S removal was investigated. EAFD from European steel plants was characterized and tested in dynamic H2S breakthrough tests and benchmarked against a commercial ZnO-based adsorbent. For this, the EAFD was first processed into adsorbents by simple milling and granulation steps. The EAFD samples exhibited sulfur capture capacities at 400 °C and an SV of 17,000 h-1 that correlated with the sample milling times and Zn concentrations. It was verified that only zinc participated in sulfur capture. Yet, both ZnO and the zinc in ZnFe2O4 were found to be active in sulfidation. At higher temperatures (500 and 600 °C), EAFD sample performance drastically improved and even exceeded the reference zinc oxide performance. The high-zinc (48% by mass) EAFD-B sample exhibited the highest tested performance at 500 °C, with a sulfur capture capacity of 234 mg g-1. The results indicate that sufficiently high-zinc-content EAFD could serve as a viable sulfur capture material.
© 2022 The Authors. Published by American Chemical Society.