Abstract: The present invention relates to a catalyst composition for ethylene oligomerization and the use thereof. Such catalyst composition includes chromium compound, ligand containing P and N, activator and accelerator; wherein the chromium compound is selected from the group consisting of acetyl acetone chromium, THF-chromium chloride and Cr(2-ethylhecanoate)3; general formula of the ligand containing P and N is shown as: in which R1, R2, R3 and R4 are phenyl, benzyl, or naphthyl. R5 is isopropyl, butyl, cyclopropyl, cyclopentyl, cyclohexyl or fluorenyl; the activatior is methyl aluminoxane, ethyl aluminoxane, propyl aluminoxane and/or butyl aluminoxane; the accelerator is selected from the group consisting of 1,1,2,2,-tetrachloroethane, 1,1,2,2-tetrabromoethane, 1,1,2,2-tetrafluoroethane, and compounds having a formula of X1R6X2, in which X1 and X2 are F, Cl, Br, I or alkoxyl, R6 is alkylene or arylene group; the molar ratio of chromium compound, ligand containing P and N, activator and accelerator is 1:0.

Abstract: The present invention relates to a catalyst composition for ethylene oligomerization and the use thereof. Such catalyst composition includes chromium compound, ligand containing P and N, activator and accelerator; wherein the chromium compound is selected from the group consisting of acetyl acetone chromium, THF-chromium chloride and/or Cr(2-ethylhecanoate)3; general formula of the ligand containing P and N is shown as: in which R1, R2, R3 and R4 are phenyl, benzyl, or naphthyl. R5 is isopropyl, butyl, cyclopropyl, cyclopentyl, cyclohexyl or fluorenyl; the activatior is methyl aluminoxane, ethyl aluminoxane, propyl aluminoxane and/or butyl aluminoxane; general formula of the accelerator is X1R6X2, in which X1 and X2 are F, Cl, Br, I or alkoxyl, R6 is alkyl or aryl; the molar ratio of a, b, c and d is 1:0.5˜10:50˜3000:0.5˜10.