Environmental protection nanometer heat conduction transformer oil and preparation method thereof

The present invention discloses an environmental protection nanometer heat conduction transformer oil and a preparation method thereof, wherein the environmental protection nanometer heat conduction transformer oil comprises ROO-R0, an antioxidant, a pour point depressant and nanometer alumina, R in the ROO-R0 is alkane or olefin having a carbon atom number of 10-23, R0 is alkyl having a carbon atom number of 2-5, and the nanometer alumina is spherical, and has the average particle size of 1-20 nm. The preparation method comprises: adopting vegetable oil as a raw material, carrying out alkali refining, detwatering, carrying out esterification alcoholysis with a lower alcohol having a carbon atom number of 2-5, terminating the neutralization, carrying out washing refining, carrying out pressure reducing distillation and decoloration filtration, adding an antioxidant, a pour point depressant and nanometer alumina, and uniformly mixing to obtain the transformer oil. According to the present invention, the advant