Abstract: A method of catalytic oxidation of a lignite using oxygen as an oxidant at atmospheric pressure is provided. The method includes the following steps, pulverizing the lignite to 200-mesh or less; drying the pulverized lignite at a temperature of 80° C. in vacuum for 10 h; weighing 0.5 g of the dried lignite and sequentially adding 10 ml of acetic acid, 0.5 mmol of a catalyst and 0.15-0.25 mmol of a cocatalyst into a round-bottom flask filled with the oxygen, keeping oxygen pressure at 0.1 MPa, reacting at a temperature of 80-120° C. for 4-12 h; using oxygen as the oxidant to catalytically oxidize the reacted lignite at an atmospheric pressure of 0.1 MPa; filtering after the reaction is finished; decompressing the filtrate to remove the acetic acid, adding a small amount of ethyl acetate to dissolve, and using an excess CH2N2/ether solution to esterify for 10 h at room temperature; and analyzing the esterified product through a gas chromatography-mass spectrometer.

Abstract: Disclosed is a method of catalytic oxidation of lignite using oxygen as an oxidant at atmospheric pressure, belonging to a method of mild oxidation of lignite. The method is used to mildly oxidize the lignite using the oxygen as the oxidant under the action of a nitroxide radical catalyst and a metal salt or metal oxide cocatalyst; the process comprises the following steps: pulverizing the lignite to 200 meshes or less, drying a pulverized coal sample at a temperature of 80° C. in vacuum for 10 h, weighing 0.5 g of the treated coal sample, sequentially adding 10 ml of acetic acid, 0.5 mmol of a catalyst and 0.15 to 0.25 mmol of a cocatalyst into a round-bottom flask, connecting a tee joint to an upper orifice of a condenser pipe, replacing oxygen in vacuum for three times so that the round-bottom flask is filled with the oxygen, keeping oxygen pressure at 0.1 MPa, reacting at a temperature of 80° C. to 120° C.