摘要
用Friedman法研究了未活化黄铁矿和机械活化不同时间的黄铁矿 (机械活化 2 0min和 40min的黄铁矿分别记为黄铁矿 1和黄铁矿 2 )在升温速率分别为 2 .5 ,5 ,7.5和 15K/min下的热分解动力学。结果表明 ,未活化黄铁矿及机械活化黄铁矿 1和黄铁矿 2的表观活化能 (E)、反应级数 (n)和指前因子 (A)分别为 :2 6 8.6 12kJ/mol,0 .42 ,1.0 94× 10 15min-1;2 43.72 5kJ/mol,0 .6 2 ,2 .0 0 8× 10 13 min -1和 177.2 88kJ/mol,0 .6 5 ,5 .92 4× 10 15min-1。对黄铁矿的X射线衍射谱进行线形分析 ,求取机械活化黄铁矿 1和黄铁矿 2的晶格畸变率 (ε)和晶块尺寸(D)。
The kinetics of the thermal decompositions of mechanically activated pyrites and non-activated pyrite were studied by using Friedman method at different heating rates of 2.5, 5, 7.5 and 15?K/min in argon. Results show that the activation energies (E), reaction orders (n) and pre-exponential factors (A) for non-activated pyrite and activated pyrites are 268.612?kJ/mol, 0.42 and 1.094×10 15?min -1 for non-activated pyrite, 243.725?kJ/mol, 0.62 and 2.008×10 13?min -1 for pyrite mechanically activated for 20?min (abbrev. Pyrite 1), 177.288?kJ/mol, 0.65 and 5.924×10 9?min -1 for pyrite mechanically activated for 40?min (abbrev. Pyrite 2), respectively. Comparing the integral width of X-ray diffraction peaks (220) and (440) of activated pyrites at different grinding time with that of non-activated pyrite, several values of lattice deformation (ε) and lattice size (D) of the crystallite were obtained. It is found that with the increase of grinding time the mechanical activation of the original material brings about a change in lattice parameters and deformation of the crystals of pyrite.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2002年第3期611-614,共4页
The Chinese Journal of Nonferrous Metals
基金
国家自然科学基金资助项目 ( 5 99340 80 )
关键词
黄铁矿
机械活化
热分解动力学
晶格畸变
pyrite
mechanical activation
kinetics of thermal decomposition
deformation of lattice structure
