Study on ZnCrOx/H-Beta bifunctional catalyst for butane synthesis from syngas

Butane is an important chemical with applications as a clean fuel and solvent. The direct conversion of syngas to butane offers a promising route to the production of high-value chemicals. However, simultaneously achieving high CO conversion and butane selectivity remains a major challenge in heterogeneous catalysis. Herein, we successfully constructed a ZnCrO x /H-Beta bifunctional catalytic system for butane from syngas. By tuning the Zn/Cr ratio in the metal oxide, the surface structure and oxygen vacancy concentration were optimized. Comprehensive characterization results reveal that a Zn/Cr ratio of 2:1 leads to optimal ZnO surface enrichment and the formation of abundant oxygen vacancies (50.1%), which efficiently promote the conversion of syngas into methanol intermediates. Subsequently, these intermediates are selectively converted to butane over the acid sites of H-Beta zeolite via hydrogenation, oligomerization, and hydrogen transfer reactions. Under optimal reaction conditions, the ZnCrO x /H-Beta catalyst achieves a high butane selectivity of 53.2% with a CO conversion of 27.0%.