(1．北京科技大學(xué) 金屬礦山高效開采與安全教育部重點(diǎn)實(shí)驗(yàn)室，北京 100083；
2．福建省雙旗山礦業(yè)有限責(zé)任公司，泉州 362509；
3. 中冶華冶(北京)國際貿(mào)易有限公司，北京 100029)
摘 要: 采用TG-DSC熱分析技術(shù)，在不同升溫速率條件下對(duì)主要載金硫化物黃鐵礦的熱分解動(dòng)力學(xué)進(jìn)行研究，并采用SEM對(duì)反應(yīng)前后的黃鐵礦微觀結(jié)構(gòu)進(jìn)行分析。結(jié)果表明：黃鐵礦熱分解的溫度區(qū)間為400~800 ℃，質(zhì)量損失率保持在26%左右；隨著升溫速率的增大，TG曲線向高溫區(qū)偏移，即得到相同轉(zhuǎn)化率所需的溫度越高，其最大反應(yīng)速率的溫度范圍為600~700 ℃。采用Kissinger法和Ozawa-Doyle法求得黃鐵礦熱分解反應(yīng)的活化能E和指前因子A分別為259.23 kJ/mol和1×1014.67。根據(jù)Coats-Redfern方程和常見的熱分解機(jī)理函數(shù)對(duì)熱重分析數(shù)據(jù)進(jìn)行線性擬合，采用Malek法進(jìn)一步確定了黃鐵礦的熱分解過程符合Mample單行法則，其反應(yīng)機(jī)理為隨機(jī)成核和隨后生長(zhǎng)，并獲得了熱分解反應(yīng)的微分方程。
關(guān)鍵字: 載金硫化物；黃鐵礦；熱分解；動(dòng)力學(xué)；熱重分析；活化能
（1. Key Laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education,
University of Science and Technology Beijing, Beijing 100083, China;
2. Fujian Shuangqishan Mining Industry Limited Company, Quanzhou 362509, China;
3. MCC Huaye (Beijing) International Trade Co., Ltd., Beijing 100029, China）
Abstract:Thermal decomposition kinetics of main gold-bearing sulfides pyrite was investigated by TG-DSC thermal analysis at different heating rates. The microstructures of pyrite before and after decomposition were analyzed by SEM. The results show that the thermal decomposition temperature of pyrite is between 400-800 ℃. The mass loss rate is approximately 26%. The TG curves move in the direction of high temperature with increasing the heating rate. This means that the same conversion can be gotten at higher temperature. The temperature range of the maximum pyrite thermal decomposition reaction rate of pyrite is between 600-700 ℃. The apparent activation energy E and pre-exponential factor A were calculated by Kissinger and Ozawa-Doyle methods, and the values are 259.23 kJ/mol and 1×1014.67, respectively. According to Coats-Redfern equation, linear regressions were carried out by common mechanism functions of thermal decomposition. It is defined that the thermal decomposition process of pyrite conforms to the Mample principle by Malek method, and the corresponding mechanism is the random nucleus and the consequent growth. The differential equation of thermal decomposition reaction was deduced as well.
Key words: gold-bearing sulfide; pyrite; thermal decomposition; kinetics; thermogravimetric analysis; activation energy
