Realizing high conversion of syngas to gasoline-range liquid hydrocarbons on a dual-bed-mode catalyst

Achieving high conversion of syngas to fuels and basic chemicals with excellent selectivity and stability remains a challenge. Here, we report an 80.6% selectivity of gasoline-range C5-11 hydrocarbons at 86.3% CO conversion over a dual-bed catalyst (CZA + Al2O3)/N-ZSM- 5( 97) that consists of an upper-bed syngas-todimethyl ether (DME) catalyst (CZA + Al2O3) and a lower-bed DME-to-gasoline catalyst ( nano-sized N-ZSM-5(97) zeolite). This dual-bed catalyst exhibits an excellent stability in a 110-h reaction test. The iso/n-paraffin ratio in the C5- 11 is up to 18. For the lowerbed zeolite catalyst, the nano- sized structure is beneficial to reduce coke and prolong lifetime; meanwhile, the low acid content is advantageous to increase C5- 11 selectivity. The 2,3-dihydro-1H-inden-1one species can be definitely detected and identified in the spent lower-bed micro- sized M-ZSM- 5( 18) catalyst. They are regarded as intermediates to generate polycyclic aromatics, which generally lead to catalyst deactivation. The dual-bed catalyst (CZA + Al2O3)/ N-ZSM-5(97) suggests a promising application in producing gasoline from syngas.