▎ 摘　　要

NOVELTY - Catalyst comprises carrier and active component, where carrier comprises nitrogen-doped graphene nano sheet and active component comprises palladium. USE - Catalyst for producing oxalic acid esters (claimed). ADVANTAGE - The catalyst has high quantity and low space-time yield of oxalic ester. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) a method for preparing catalyst, which involves mixing graphene nano sheet which is placed in ammonia atmosphere at 400-80 degrees C for not less than 3 hours to obtain nitrogen-doped graphene nano sheet; (2) placing nitrogen-doped graphene nano sheet in solution containing palladium element and undergo ultrasonic processing and separating to obtain solid phase; washing, drying and calcining solid phase in atmosphere containing reducing gas at 150-450 degrees C for 2 hours; and (3) cooling reaction mixture to room temperature in atmosphere containing reducing gas to obtain catalyst; and (4) a method for producing oxidative coupling, which involves coupling carbon monoxide is oxidatively to produce oxalate in fixed bed reactor; (5) contacting feed gas containing carbon monoxide and nitrite with catalyst, Where volume ratio of carbon monoxide and nitrite is 1.1:1.8; and (6) reacting reaction mixture with gas phase airspeed of raw material gas at 90-150 degrees C and gas space velocity of raw material gas of 2-5 liter.g-1.h-1.