Efficient Ni/CaCeOx dual-functional materials for integrated CO2 capture and dry reforming of methane for syngas production

Ni/CaCeO x achieves efficient integrated CO 2 capture and dry reforming of methane. • CeO 2 reduces the CO 2 capture temperature and facilitates its conversion at 600 °C. • Ni/Ca 0.6 Ce 0.4 O x -R demonstrated an H 2 yield of 63.67 mmol/g DFMs and a CO 2 conversion exceeding 95% at 600 °C. • Reverse Boudouard reaction plays a critical role in facilitating CO 2 conversion. Integrated CO 2 capture and conversion (ICCC) using CaO based adsorbents is a promising method for industrial carbon reduction, but its application is constrained by challenges such as high operating temperatures, CaO sintering, carbon deposition on Ni sites. In this work, CeO 2 was introduced into Ni/CaO to synthesize Ni/CaCeO x dual-functional materials (DFMs) with regulated oxygen vacancies. By tailoring the morphology of CeO 2 the oxygen vacancy concentration and capture-conversion performance were effectively tuned. The incorporation of CeO 2 significantly promoted low-temperature CO 2 uptake and reduced the activation energy of dry reforming of methane (DRM) reaction, lowing the operating temperature by more than 50 °C compared to previously reported ICCC-DRM studies. Among the prepared materials, the CeO 2 -introducted and reduced Ni/Ca 0.6 Ce 0.4 O x -R catalyst showed the best performance, reducing the CO 2 uptake temperature from the theoretical 600 °C to 410 °C. Under isothermal ICCC conditions at 600 °C, it achieves H 2 and CO production rates of 63.65 mmol/g DFMs and 56.74 mmol/g DFMs , respectively, while carbon elimination reached 35.06 mmol/g DFMs . Notably, the DFM exhibits excellent cycling stability, with only 10.08% loss in H 2 yield and 8.40% loss CO 2 conversion after 10 cycles. This work demonstrates that oxygen-vacancy control by CeO 2 modification is an effective route to improve the efficiency and stability of CO 2 capture and conversion. Download: Download high-res image (155KB) Download: Download full-size image