Comparative study on reaction characteristics of micron-sized aluminum and nano-sized aluminum in O_2 and CO_2 environment

摘要

To understand the difference in reaction behavior of micron/nano Al powder in O_2 and CO_2 environment at 25-1500 °C, thermal analysis experiment for 50 nm and 1.5 μm Al powder was performed in this study. The experimental results show that the reaction of 50 nm and 1.5 μm Al powders with O_2 mainly occurs at 530 - 575 °C and 775 - 1500 °C, respectively. In CO_2 environment, the reaction of 50 nm and 1.5 pm Al powders with CO_2 mainly occurs at 445 - 955 °C and 590 - 1130 °C, respectively. For reaction products, most of the reaction products condensed together and form agglomerated Al_2O_3 in O_2 environment. However, in CO_2 environment, because the oxidation reaction rate and reaction heat between Al and CO_2 are lower than that between Al and O_2, the particles of the reaction product are still relatively independent. The experimental results clearly show the reaction characteristics of micron/nano Al powder in O_2 and CO_2 environment at 25- 1500 °C, which is of great significance for the study of ignition and combustion mechanism of Al powder.