Thermodynamic properties and reaction mechanism of coal reductive decomposition phosphogypsum to prepare CaO and SO_(2)  

作　　者：Pengxing Yuan Meng Li Shiyi Chen Wenguo Xiang 

机构地区：[1]Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education,School of Energy and Environment,Southeast University,Nanjing 211189,China [2]SINOPEC Nanjing Engineering&Construction Incorporation,Nanjing 210049,China [3]College of Chemical and Biological Engineering,Zhejiang University,Hangzhou 310058,China

出　　处：《Chinese Journal of Chemical Engineering》2025年第3期135-144,共10页中国化学工程学报(英文版)

基　　金：financial support by the Phosphogypsum Low-Temperature Decomposition to Produce Calcium-Based Materials and Sulfuric Acid Raw Gas Technology(Horizontal Project)(8503009049);National Natural Science Foundation of China(52376101).

摘　　要：The thermal effects,spontaneity and proceeding degree of 32 chemical reactions during coal reductive decomposition phosphogypsum(PG)to prepare CaO and SO_(2)are analyzed utilizing thermodynamic theory and method.The ideal reaction temperature for PG decomposition and desulfurization is 1173-1273 K.The 10 key chemical reactions controlling coal reductive decomposition PG have been selected.The heat release of critical exothermic reactions can satisfy the autothermal operation of PG decomposition and desulfurization process.Meanwhile,the spontaneity of oxidation reactions has thermodynamically priority over reduction reactions.But the reaction mechanism shows that the oxidation of CaS by O_(2)is in parallel competition with the reduction of CaSO_(4)by CO and C.Furthermore,clarifying the regulatory mechanisms of PG decomposition temperature and reaction atmosphere(reducibility and oxidation)is beneficial for maximizing the production of CaO and SO_(2).

关 键 词：PHOSPHOGYPSUM COAL THERMODYNAMIC Reductive decompositio 

分 类 号：TQ536.9[化学工程—煤化学工程]