| This article intended to provide theoretical foundation for the preparation of coal-based composites through the investigation of the photo-catalytic oxidation characteristics of coal. Ultra fine coal was prepared using airflow pulverize device and grade methods. Based on the determination of saturation adsorption of some transition metal ion in coal, coal samples load with transition metal ions were prepared by mechanical chemistry interaction method. Pore structure analysis showed that the average aperture, specific surface area and pore volume were increased. The change of weightlessness in the course of photo-catalytic oxidation of coal was measured by manual artificial climate accelerate device. The different influencing factors of photo-catalytic oxidation of coal were analyzed. The effect of oxygen flow and the particle size of coal on photo-catalytic oxidation of coal was studied, and the results showed that the effect of outside diffusion and inside diffusion could be eliminated by choosing 30ml/min oxygen flow and 1250 mesh particle. Characteristics and different influencing factors on photo-catalytic oxidation of coal were studied. Results showed that light intensity and temperature accelerated the process of photo-catalytic oxidation; little particle coal caused great cumulate weightlessness; low rank coal has better reactivity than high rank coal; cumulate weightlessness of vitrain was more than that of fusain; fusain had great reaction rate in initial stage; the transition metal ions such as Fe3+,Co2+,Ni2+,Cu2+ and Zn2+ were catalyst promoter for photo-catalytic oxidation of coal, among which Co2+ was the best catalyst promoter. The structure of reactant and reaction product was determined by FTIR,SEM and XEDS. The results indicated the red shift of hydroxyl absorb peak at 3439cm-1 after loading with Co2+; the content of carbon decrease and the content of oxygen increase in coal (load with Co2+) after photo-catalytic oxidation. During the course of photo-catalytic oxidation of coal, the content of humic acids increase at first and then decease, but the swelling capacity decrease. These results suggested that some bonds were broken and more opened system were formed in coal structure. From the photo-catalytic oxidation of different maceral in coal, it was found that fusain had great reaction rate in initial stage. Based on the kinetics analysis of photo-catalytic oxidation of coal, it was found that two reaction stage occurred during the photo-catalytic oxidation; the activation energy of photo-catalytic oxidation of coal decrease after load with Co2+; apparent reaction order is 0.6; the apparent reaction kinetics equation is . Finally, this paper provided some beneficial theoretical support for the preparation of coal-based composite by systematic study.
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