(1. 西安建筑科技大學(xué)冶金工程學(xué)院，西安710055; 2. 中南工業(yè)大學(xué)冶金系，長(zhǎng)沙410083)
摘 要: 研究了碳酸錳熱解過(guò)程的動(dòng)力學(xué)，確定了有關(guān)動(dòng)力學(xué)參數(shù)。在熱解過(guò)程中，MnCO3離解符合收縮核模型，MnO氧化符合顆粒模型。MnCO3離解為化學(xué)反應(yīng)所控制，MnO氧化的前期是混合控制，氧化后期是擴(kuò)散控制，氧氣在MnO2產(chǎn)物層中的擴(kuò)散是MnO氧化的限制環(huán)節(jié)。加快MnO氧化速率的有效方法是改變MnO2產(chǎn)物層的結(jié)構(gòu)，使其多孔疏松，以此增大氧氣的擴(kuò)散系數(shù)。
關(guān)鍵字: 碳酸錳；熱解；動(dòng)力學(xué)
（1. College of Metallurgy, Xi'an University of Architecture and Technology, Xi'an 710055, P.R.China;
2. Department of Metallurgy, Central South University of Technology, Changsha 410083, P.R.China）
Abstract:The kinetics on the thermal decomposition of MnCO3 was investigated. The parameters in the kinetic equations were worked out. The results showed that the decomposition reaction of MnCO3 follows the shrinking core model, and the control step is chemical reaction; the oxidation of MnO obeys the grain pellet model, during the initial period, the oxidation reaction is simultaneously controlled by reaction and diffusion, and later by diffusion only. The diffusion of oxygen in MnO2 products layer is a restraining factor of MnO oxidation, the effective method of speeding up MnO oxidation rate is changing the structure of the MnO2 products layer in order to make it become porous, loosened and enlarged the diffusion coefficient of oxygen.
Key words: MnCO3; thermal decomposition; kinetics
