No abstract

Dry reforming of methane (DRM) can convert greenhouse gases (CO2 and CH4) into value-added syngas (CO and H2), which is one of the promising approaches to achieve carbon neutrality. Designing coking resistant catalysts is still a challenge for an efficient DRM reaction. Here, we developed an efficient binary Mo–Ni catalyst through elucidating the promotional role of Mo in boosting the coking resistance of Ni-based catalysts during the DRM. Mo-modified ZSM-5 served as the “smart support”, which provided the dynamic variation between MoO x and MoO x C y , enabling efficient carbon removal during the DRM reaction. Furthermore, the introduction of Mo maintained more active Ni0 species and enhanced the activity. A more effective pathway via a formate intermediate driven by the Mo-modified Ni/ZSM-5 further suppressed coking during DRM. This work discovered that both activity and coking resistance of traditional Ni catalysts can be simultaneously improved due to the addition of Mo through restraining Ni oxidation and a unique MoO x ↔ MoC x O y redox cycle.

Selective catalytic reduction (SCR) of NO x using NH3 in the presence of alkaline and heavy metals is still an issue in the application of a stationary source. Reported here is the rational design of a novel H-SAPO-34-supported ceria-promoted copper-based catalyst (CuCe/H-SAPO-34) that demonstrates exceptional resistance against alkali (K), alkaline earth (Ca), and heavy metal (Pb) poisoning during SCR of NO x . The H-SAPO-34 support contained numerous acid sites that allowed Cu-based catalysts to maintain their catalytic activity while also resisting poisoning by K and Ca. Decorating the catalyst with CeO2 promoted the low-temperature deNO x activity by accelerating the redox cycle with Cu species and assisted the H-SAPO-34 in capturing Ca and Pb. H-SAPO-34-supported ceria-promoted copper oxide catalysts prevented the irreversible combination of K, Ca, or Pb with the active centers, providing the catalyst with excellent poisoning resistance. This work provides a strategy for the development of high-performance, poisoning-resistant catalysts for NH3–SCR of NO x in the presence of alkaline and heavy metals.