▎ 摘　　要

NOVELTY - Preparation of a cryogenic nitrogen-doped graphene supported nano palladium catalyst includes adding aqueous graphene oxide solution in 0.93-3.7 mmol nitrogen source, stirring at room temperature for 1 minute, crystallizing for 8-16 hours at 120-180 degrees C, filtering, rinsing with deionized water, and drying overnight at 80 degrees C to obtain nitrogen-doped graphene; and adding to deionized water, carrying out ultrasonic treatment at 50 degrees C for 3 hours, adding 0.4-0.02 mol/L palladium chloride aqueous solution, dripping 0.5-2 mL reducing agent, centrifuging, and vacuum drying at 60 degrees C for 2 hours. USE - Method for the preparation of a cryogenic nitrogen-doped graphene supported nano palladium catalyst (claimed) used for hydrogenation reaction of olefin. ADVANTAGE - The catalyst has good reusability, and is prepared using simple and inexpensive method. DETAILED DESCRIPTION - Preparation of a cryogenic nitrogen-doped graphene supported nano palladium catalyst comprises: (A) adding 2 mg/mL graphite oxide to deionized water, and ultrasonic processing for 1.5 hours to obtain a highly dispersed aqueous graphene oxide solution; (B) adding the aqueous graphene oxide solution in 0.93-3.7 mmol nitrogen source, stirring at room temperature for 1 minute, charging in a hydrothermal reaction kettle, crystallizing for 8-16 hours at 120-180 degrees C, filtering, rinsing with deionized water, and drying overnight at 80 degrees C to obtain different nitrogen-doped graphene; and (C) adding the nitrogen-doped graphene to deionized water to obtain a concentration of 1 mg/mL, carrying out ultrasonic treatment at 50 degrees C for 3 hours, adding 0.4-0.02 mol/L palladium chloride aqueous solution, magnetically stirring while slowly dripping 0.5-2 mL reducing agent at room temperature with stirring for 30 minutes, centrifuging, water washing for 5 times, and vacuum drying at 60 degrees C for 2 hours.