The invention discloses an
iridium picolinate complex catalyst for synthesizing
acetic acid by
methanol carbonylation and a preparation method and an application thereof, a ligand of the catalyst is a
copolymer of 2-
vinyl pyridine and
methyl acrylate, and a
copolymer iridium complex catalyst is formed by the complexation reaction with an
iridium compound. The preparation method comprises the steps of preparing the ligand of the catalyst, then dissolving 1 part by weight of the
copolymer in 10-100 parts by weight of the
acetic acid, stirring, heating under
reflux, adding the
iridium compound which accounts for 3-10% of the weight of the copolymer, carrying out reaction for 10-60min, cooling to the
room temperature, using
ether for
precipitation, filtering and then obtaining a copolymer iridium catalyst. The 1 part by weight of the copolymer is added into the
acetic acid solution containing (Ir(CO)2I)2 or (Ir(CO)2Cl)2 under stirring, the feeding is 3-10% of the weight of the copolymer calculated by the weight of iridium, the reaction is carried out for 10-30min under stirring, the
ether is used for
precipitation, and the copolymer iridium catalyst is obtained by filtering. The copolymer iridium catalyst is used for preparing the acetic acid by
methanol carbonylation reaction and has good catalytic performance.