▎ 摘　　要

NOVELTY - A catalyst comprises components (A) and (B) compounded together by mechanically mixing. The active component of component (A) is a metal oxide. The component (B) is SAPO-17 molecular sieve with ERI topology structure. The metal oxide is manganese oxide, manganese chromium oxide, manganese aluminum oxide, manganese zirconium oxide, manganese indium oxide, zinc oxide, zinc chromium oxide, zinc aluminum oxide, zinc gallium oxide, zinc indium oxide, cerium dioxide, gallium(III) oxide, indium(III) oxide, zinc-aluminum-manganese oxide, and/or indium-gallium-manganese oxide. The specific surface area of manganese oxide, zinc oxide, cerium dioxide, gallium(III) oxide and indium(III) oxide is 1-100 m2/g. The specific surface area of manganese chromium oxide, manganese aluminum oxide, manganese zirconium oxide, manganese indium oxide, zinc chromium oxide, zinc aluminum oxide, zinc gallium oxide, zinc indium oxide, zinc-aluminum-manganese oxide and indium-gallium-manganese oxide is 5-150 m2/g. USE - The catalyst is useful for direct conversion of synthesis gas to produce low-carbon olefin including ethylene and propylene (claimed). ADVANTAGE - The catalyst ensures high product yield, and has high selectivity. DETAILED DESCRIPTION - A catalyst comprises components (A) and (B) compounded together by mechanically mixing. The active component of component (A) is a metal oxide. The component (B) is SAPO-17 molecular sieve with ERI topology. The metal oxide is manganese oxide (MnOx), manganese chromium oxide (MnCryO(x+1.5y)), manganese aluminum oxide (MnAlyO(x+1.5y)), manganese zirconium oxide (MnZryO(x+2y)), manganese indium oxide (MnInyO(x+1.5y)), zinc oxide, zinc chromium oxide (ZnCryO(1+1.5y)), zinc aluminum oxide (ZnAlyO(1+1.5y)), zinc gallium oxide (ZnGayO(1+1.5y)), zinc indium oxide (ZnInyO(2+1.5y)), cerium dioxide, gallium(III) oxide, indium(III) oxide, zinc-aluminum-manganese oxide (ZnyAlzMnO(x+1.5y+1.5z)), and/or indium-gallium-manganese oxide (InyGazMnO(x+1.5y+1.5z)), where x is 1-3.5, and y and z are 0.1-10. The specific surface area of manganese oxide, zinc oxide, cerium dioxide, gallium(III) oxide and indium(III) oxide is 1-100 m2/g. The specific surface area of manganese chromium oxide, manganese aluminum oxide, manganese zirconium oxide, manganese indium oxide, zinc chromium oxide, zinc aluminum oxide, zinc gallium oxide, zinc indium oxide, zinc-aluminum-manganese oxide and indium-gallium-manganese oxide is 5-150 m2/g. An INDEPENDENT CLAIM is included for direct conversion of synthesis gas to produce low-carbon olefin, which involves subjecting synthesis gas as reaction raw material to conversion reaction on a fixed bed or a moving bed in the presence of the catalyst.