Zirconium-based catalytic system and method for preparing linear alpha-olefin by catalyzing ethylene oligomerization through zirconium-based catalytic system

The invention belongs to the field of catalytic polymerization reaction, and discloses a zirconium-based catalytic system and a method for preparing linear alpha-olefin by catalyzing ethylene oligomerization through the zirconium-based catalytic system. The zirconium-based catalytic system comprises a component A, a component B and a component C, wherein the component A is a main catalyst, and the general formula of the main catalyst is (RCOO) nZrOCl2-n; wherein R is alkyl or cycloalkyl, and n is equal to 1 or 2; the component B is a cocatalyst, and the cocatalyst is an organic aluminum compound; the component C is an additive, and the chemical general formula of the additive is R1R2AlX or R12AlX; in the formula (I), R1 is an alkoxy group or an aryloxy group of C1 to C15; r2 is an alkyl group of C1 to C10, a cycloalkyl group of C3 to C10, an aralkyl group of C7 to C10, and an aryl group of C6 to C10; x is halogen. The zirconium-based catalytic system has good solubility in alkane, is used for catalyzing ethyl