Method for preparing 2-methyl pentamethylene diamine and 3-methylpiperidine by hydrogenation of 2-methyl-pentanedinitrile

The invention provides a method for preparing 2-methyl pentamethylene diamine and 3-methylpiperidine by hydrogenation of 2-methyl-pentanedinitrile, and relates to a catalyst. The method comprises the following steps: doping a raney nickel catalyst in Fe, Cr and Yb; in the presence of an alkaline cocatalyst, diluting the 2-methyl-pentanedinitrile by using a solvent, and carrying out hydrogenation reaction to obtain the 2-methyl pentamethylene diamine and the 3-methylpiperidine. By doping of addition agents in the raney nickel catalyst, high total yield of the 2-methyl pentamethylene diamine and the 3-methylpiperidine can be realized under gentle hydrogenation reaction conditions. The 2-methyl-pentanedinitrile is completely subjected to hydro-conversion, the yield of the 2-methyl pentamethylene diamine and the 3-methylpiperidine is quite high, and heavy or high-boiling-point compounds with low economic value are avoided.