Behavior and evolution of the hydrocarbon generation from the organic matter in coal under the occurrence of molybdenum is poorly understood. Thus, a set of the catalytic simulation for the gas generation of the coal sample with addition of elemental molybdenum was carried out with the gold tube autoclave. It was found that the peaks of total and monorneric hydrocarbon gas generation occurred whether or not to add molybdenum, which indicates that there is still large potential for methane generation in very high maturity stage with simulated vitrinite reflectance (SVR) greater than 4.0 percent. Added molybdenum had a weak suppression on the gas hydrocarbon generation from the coal when the SVR was less than 3.0 percent. The promotion to a certuin extent occur after the SVR is more than 3.0 percent. Interrelationship of the methane yields between the raw and molybdenum-added coal samples was similar to that of total gaseous hydrocarbon yield, the ethane yield of the molybdenum-added sample was higher than that of the raw sample coal once the SVR exceeds to 3.0 percent, and the propane to pentane yields under the occurrence of molybdenum were slightly higher than or approximately equal to those from the raw samples after their generation peaks. It was suggested that the added molybdenum was not involved in the early to medium staqes of the hydrocarbon generation through a thermal degradation, but played a promoting effect on late thermal cracking hydrocarbongeneration, possibly resulting from the differences of the catalytic reaction space during various maturation stages of coal.%关于钼作用条件下的煤中有机质生烃特征和演化过程,目前知之甚少.为此,利用黄金管高压釜装置,以原煤中添加单质钼的方式,开展了催化生气模拟实验.研究发现,无论加钼与否,煤样气态烃和单体烃气的产率均存在一个生成高峰,在模拟镜质组反射率大于4.0％之后的极高成熟度阶段仍存在较大的甲烷生成潜力；当模拟镜质组反射率小于3.0％时,添加的钼对煤中有机质生气具有微弱的抑制效应,此后阶段中才体现出一定的促进作用；原煤与加钼煤样甲烷产率之间的相互关系与气态烃总产率大致相似,加钼煤样乙烷产率在镜质组反射率大于3.0％之后高于原煤,加钼条件下丙烷一戊烷的产率在其生成高峰之后略高于或约等于原煤.分析认为,添加的钼没有参与煤中有机质的早-中期热降解生烃过程,但对晚期热裂解生气作用起到了一定的促进效应,原因可能在于煤中催化反应空间在不同的成熟演化阶段存在一定的差异.
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