TG-MS STUDY ON THE EVOLVED GASES DURING PYROLYSIS OF MACERALS FROM SHENMU COAL

摘要

Pyrolysis is a useful tool for the examination of structure and (activity of coal if coal pyrolysis is performed under precisely definite conditions, in particular, non-isothermal pyrolysis at constant heating rate. The mechanistic and khetic data on the decomposition of coal and much valuable information about the formation of numerous single products as a function of temperature could be obtained. Van Heek investigated the possibilities and limitations of experimental and theoretical methods of non-isothermal reaction kinetics applied to the relation between coal structure and pyrolysis behavior. They studied the evolution curves of some evolved gases such as CH_4 C_3H_8 and H_2O during coal pyrolysis and compared with those of model compounds. Das studied the evolution characteristics of gases during pyrolysis of maceral concentrates of different rank Russian coal using TGGC. They found the major constituents of gaseous products were CH_4, CO and H_2. And vitrinite of any rank was found to yield a higher amount of CH_4 and lower amount of CO than fusinite. The previous works on pyrolysis behavior paid much attention on the effect of coal rank, few studies was carried out on the pyrolysis behaviors of individual macerals, especially those separated from the same parent coal. The aim of this work is to study the evolution behavior of evolved gases during pyrolysis of macerals separated from Chinese Shenmu coal and get more information about the relationship between maceral structural characteristic and its pyrolysis behavior.