差示扫描量热法对Fe1-xO歧化反应的研究

摘要

采用差示扫描量热法研究了维氏体歧化反应发生的温度、歧化率以及助催化剂对歧化反应的影响.结果表明,随着维氏体中铁离子缺位浓度(Fe2/Fe3+)的增大,歧化率逐渐降低.助催化剂对Fe1-xO的歧化反应有抑制作用,研究的助催化剂中,CaO、MgO、ZrO2和V2O5对Fe1-xO的歧化抑制作用较强,这与它们能很好地溶解于铁氧化物晶粒中有关；Al2O3、TiO2、K2O、CeO2和混合稀土氧化物对Fe1-xO歧化反应的抑制作用较弱.多助催化剂的联合使用能够有效抑制Fe1-xO歧化反应的发生,不同样品发生歧化反应的温度相差不大,起始温度约为260℃,峰顶温度约为320℃,终止温度约为400℃.%The influence of disproportionation temperature and disproportionation rate of wustite ( Fe1-xO) and the promoters on disproportionation was investigated by means of differential scanning calorimetry (DSC). The results showed that the disproportionation rate decreased with the increase of Fe 2+/Fe3 + vacancy concentration. The promoters such as CaO, MgO, ZrO2 and V2O5 possessed strong inhibition for Fe1_xO disproportionation due to their good solubility in iron oxide crystal,and A12O3 ,TiO2 ,K2O,CeO2 and mixed rare earth oxide had weak inhibition for the disproportionation; the combined use of multi-pro moters could effectively inhibited Fe1-xO disproportionation. Disproportionation temperature of different catalysts were almost the same; The initial temperature, peak temperature and final temperature were generally about 260 ℃ ,320 ℃ and 400 ℃respectively.