Hydrogenation of fatty acid methyl ester over Pd nanoparticles stabilized by thermoregulated ionic liquid

•The thermoregulated phase-separation Pd nanoparticles catalytic system were synthesized and characterized.•The prepared nanoparticle catalytic system has high stability and high dispersibility.•The catalytic system had an excellent catalytic performance and reusability for the hydrogenation of fatty acid methyl ester.