| This article intended to provide theoretical foundation for the preparation of coal-based dergradable composites through the investigation of characteristics of the low temperature thermal oxidation reaction(LTTOR) of coal. Using acid-washed SF Coal(ASFC), the different coal samples(d2:1.35~1.375g.cm-3 d3: 1.375~1.4g.cm-3 d4:+1.4g.cm-3) was obtained by means of sink-float method. The research samples loaded with transition metal ions and nano-TiO2 as catalyst, were prepared by using ion exchange method. The thermal oxidation degradation reactivities of AFSF, its differenct density components were studied, and the effect of transition metal and nano-TiO2 on their thermal oxidation degradation reactivities were also investigated in TG, fixed bed reactor,The oxidaton reaction kinetics were further studied based on the results from TG analysis and test of oxidative degradation reaction in fixed bed reactor. The structure and thermal oxidation reactivity of AFSF, its differenct density components were studied by FTIR, element analysis, TG analysis and test of oxidative degradation reation in fixed bed reactor. TG analysis show that different density samples have different thermal oxidation mass loss reactivity, the reactivity order is in the sequence of d2>d3～d4.In fixed bed reactor, the order is d2>d3>d4,but the CO2 released amount is in the order of d4>> d3~d2. That is because d2 and d3 samples have higher aliphatic structure uinit and higher H/C ratio, but have lower mineral matter. It can be guessed that gas producs of oxidation of d2 and d3 samples contain other small molecule hydrocarbon beside of CO2 , mineral matter may has catalysis on production of CO2 from thermal oxidation of d4 due to deep catalytic decdomposing of them. Ion exchange of ASFC and different density components with with transition metal cation and TiO2 were conducted by impregnating method and mechanical chemistry method.The TG analysis have proved that mechanical chemistry method is more effective than impregnating method for the catalytic oxidation of the coals. In the range of research temperature, Co3+in ion exchanged ASFC and its different density components by impregnating method has the most negative catalysis on the mass loss reactivity of them in thermal oxidation, whereas d3 loaded TiO2+Ni by mechanical chemistry method has more effective catalysis on mass loss reativity than d3. The results of oxidative degradation reaction of d3 loaded transition metal cation and TiO2 by mechanical chemistry method show that TiO2 has the most effective catalyst for mass loss reativity of d3. FTIR analysis showed the methylene group, connected with the aromatic ring in ASFC and differernt density components, have higher reactivity during the LTTOR in fixed bed reactor. The degree of equillibrium swelling of oxidized ASFC, varied with the change of its oxidation time and temperature, arrived maximum at 80 ℃ while oxidation time at 15h , and then decreased sharply with oxidation time, but slow decreased at 60℃ with oxidation time, and that of oxidized ASFC at 80℃ is larger than that at 60 ℃ at any oxidation time. The content of humid acids of oxidized ASFC, d3and d4 appeared a maximum while the oxidation time arrived 26h at 60℃ , and increase extent of their humid acids content at this condation is in the sequence of: d4>d3>ASFC. This is consistent with the order of CO2 released amount at the same oxidation temperature. This results showed that humid acids is the intermediate products and the major source of CO2 for LTTOR of the coals. The kinetics of LTTOR of the coals was disscussed and the kinetic equations were established with hypothesis that LTTOR of the coals in TG and fixed bed reactor is a simple oxidaton decomposing reaction. The kinetics of LTTOR of d3 and d3 loaded TiO2+Ce by mechanical chemistry method(J-d3-TiO2+Ce) was divided into two period at 120 ℃, and their activate reaction energy in LTTOR were calculated by using Coast-Redfern.method according to the results of their TG analysis. The results show that in the first per...
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