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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 H 2 S to form stable sulfides. Hence, the valorization potential of EAFD as an adsorbent material for syngas H 2 S removal was investigated. EAFD from European steel plants was characterized and tested in dynamic H 2 S 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 ZnFe 2 O 4 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.

The thermal stability of magnetron sputtered solar absorber coatings was investigated at temperatures of 200-500°C. Diffusion barriers of aluminium (Al) and tantalum nitride (TaN x ) were studied against thermal diffusion of copper substrate atoms. The diffusion barriers studied were experimental DC magnetron sputtered Al and TaN x layers between a copper substrate and an absorber coating. The absorbers were aged by means of heat treatment in air. The influence of diffusion barriers was analysed by optical and microstructural analyses before and after the ageing procedures. Without a barrier coating, copper substrate atoms diffused through the absorber to the surface, which degraded optical selectivity. The diffusion can be prevented or retarded with a dense diffusion barrier layer. The 500-nm-thick Al barrier layer prevented Cu diffusion and retained optical selectivity at 300°C. At higher temperatures, diffusion was observed but the Al barrier retarded the degradation when compared to an absorber without the barrier layer.

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