We examined the conversion of HFC-134a over five catalysts, Na2CO3, CaO, CaCO3, and two types of γ-Al2O3 with different surface areas, between 300 and 600 °C. HFC-134a was barely converted via the non-catalytic reaction, even at the highest temperature (600 °C). The operating temperatures for the catalytic conversion of HFC-134a were reduced dramatically and its efficiency increased with increasing temperature. Among the catalysts used, γ-Al2O3 with the larger surface area showed the highest conversion rate of HFC-134a, which was followed, in order, by γ-Al2O3 with the smaller surface area, CaCO3, CaO, and Na2CO3. The conversion rate of γ-Al2O3 decreased rapidly due to catalyst deactivation. The catalytic efficiency of γ-Al2O3 was maintained for a longer period by water addition. Water acted as a hydrogen donor for the dehydrofluorination reaction.
Catalytic conversion of 1,1,1,2-tetrafluoroethane (HFC-134a)
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