Method for producing lubricant oil base oil

A method for producing a lubricating base oil, the method comprising:

• a first step of performing a 13C-NMR analysis with respect to an oil to be treated containing a normal paraffin and an isoparaffin, and selecting the oil to be treated based on the following index values (1), (2) and (3) in an obtained 13C-NMR spectrum,
• index value (1):
• a value obtained by dividing an integrated value of a peak assigned to a tertiary carbon atom by an integrated value of all peaks at 0 to 50 ppm,
• index value (2):
• a value obtained by dividing an integrated value of a peak assigned to a carbon atom constituting a hydrocarbon main chain by the integrated value of all peaks at 0 to 50 ppm, and
• index value (3):
• a value obtained by dividing an integrated value of a peak assigned to a branched CH3 bonded to a fifth carbon atom or a carbon atom on an inner side thereof from a terminal carbon atom in the hydrocarbon main chain by an integrated value of all peaks at 10 to 25 ppm;
• and
• a second step of obtaining a dewaxed oil by isomerization dewaxing of the oil to be treated selected in the first step, wherein
• the first step is a step of selecting the oil to be treated having the index value (1) of 0.01 to 0.1, the index value (2) of 0.2 to 0.6, and the index value (3) of 0.05 to 0.2, and
• the second step is a step of performing isomerization dewaxing of the oil to be treated selected in the first step at a reaction temperature of 280 to 360° C.