▎ 摘　　要

NOVELTY - Iron/graphene catalyst comprises 3-90 pts. wt. iron element or its oxide or hydroxide, 0.05-10 pts. wt. one element or its oxide including potassium and sodium, and 15-90 pts. wt. graphene. USE - The iron/graphene catalyst is useful in directly producing alpha -olefins from syngas (claimed), and preparing long-chain alpha olefins from synthesis gas. ADVANTAGE - The catalyst: has controllable uniform rod structure, and has low selectivity of target products and high selectivity of low-carbon olefins in the technology of preparing long-chain alpha olefins from synthesis gas. DETAILED DESCRIPTION - INDEPNDENT CLAIMS are also included for: (1) preparing the iron/graphene catalyst comprising (a) preparing graphite oxide by Hummer method, washing, and ultrasonically treating to obtain uniform solution of graphene oxide, (b) adding iron salt solution to graphene oxide aqueous solution and stirring uniformly to obtain material A, (c) ultrasonically treating the material A, adding alkali, adjusting the pH value to 8-12 to obtain material B, (d) passing material B into hydrothermal kettle for hydrothermal treatment, (e) washing with large amount of mixed solution of deionized water and ethanol, centrifuging, and drying the catalyst in an oven to obtain customized iron/graphene catalyst, and (f) crushing iron/graphene catalyst, sieving, heat-treating and calcining under protective atmosphere, and cooling; and (2) use of iron/graphene catalyst in directly producing alpha -olefins from syngas, where the reaction conditions of the catalyst used in the synthesis of alpha -olefins from synthesis gas are: small fixed-bed reactor having a catalyst loading of 3 ml at 240-340 degrees C under reaction pressure of 0.5-5 MPa in a volume ratio of hydrogen to carbon monoxide in the synthesis gas of 0.67-3 in a space velocity of 3-50 l.g-1 cat.H-1, the selective performance of alpha -olefin in hydrocarbons reaches 65%, and the catalyst can run continuously and stably for 3000 hours.