纳米金属氧化物对HMX的催化热分解

Catalytic Effects of Nano Metal Oxides on the Decomposition of HMX

用PDSC、TG和等温TG方法考察了九种纳米金属氧化物对HMX热分解过程的影响。结果发现,HMX熔融之前,金属氧化物使HMX固相分解增大,尤其是PbO、Al2O3和TiO2大大地催化了HMX的固相分解,3MPa压力下PbO和Al2O3使HMX的固相放热抵消了HMX的熔融吸热,使熔融峰消失。PbO也催化了高压下HMX的液相分解,但Al2O3和TiO2对液相分解的作用不大。低升温速率TG结果和低于HMX熔融温度的等温TG试验结果与常压DSC固相分解的结果一致,其结果更有利区分纳米与非纳米材料的不同催化作用。

The effects of nine nano metal oxides, including Co3O4, Fe2O3 , Bi2O3 , CuO, PbO, Al2O3 , TiO2, NiO and PbO/CuO, on thermal decomposition of HMX were investigated by PDSC,TG-DTG and iso-TG. The results show that the decomposition of HMX in solid phase before melting is advanced by the metal oxides, especially PbO, Al2O3 and TiO2 , and the endothermic melting peak of HMX mixed with PhO and Al2O3 even disappear entirely, owing to the compensation of exothermic decomposition in solid phase at pressure. Thermal decomposition of HMX in liquid phase at high pressure of 3 MPa is catalyzed by PbO,hut not affected by Al2O3 and TiO2. The results of TG-DTG at lower heating rates and iso-TG under HMX melting temperature are in agreement with those of DSC in solid decomposition at ambient pressure. These results are advantageous to the identification of the different effects of nano and normal metal oxides. The catalytic decomposition of HMX by nano and normal metal oxides, including CuO, PbO, Al2O3 and TiO2 ,were also characterized by the kinetic parameters obtained from isothermal and non-isothermal TG. The kinetic parameters obtained from isothermal TG are in agreement with those from non-isothermal. The catalytic effects characterized by means of kinetic parameters consist also with those by DSC and TG-DTG. The decrements of Ea values of the decomposition of HMX with three nano materials,except CuO,are more than that of those with normal materials.