间二甲苯气相氨氧化反应行为及原料利用率分析

Analysis on reaction behavior and raw material utilization efficiency for gas phase ammoxidation of m-xylene

利用固定床反应装置研究了间二甲苯气相氨氧化制备间苯二甲腈(IPN)的反应行为。考察了反应n(NH_(3))∶n(间二甲苯)(氨比)、n(空气)∶n(间二甲苯)(空比)、温度、停留时间等反应工艺参数对间二甲苯转化率及产物分布的影响,构建了间二甲苯气相氨氧化反应路径,并分析了不同工况条件下间二甲苯(碳)、O_(2)、NH_(3)沿各反应路径的利用情况。实验结果表明,间二甲苯氨氧化生成IPN的过程由一系列复杂的平行-连串反应所构成;深度氧化以及NH_(3)燃烧消耗了大量的碳、O_(2)、NH_(3);合适的反应氨比、空比、温度和停留时间有助于提高原料的有效利用率;利用分区强化的反应新工艺,可有效减少NH_(3)和O_(2)的损耗。

The reaction behavior of gas phase ammoxidation of m-xylene(mx)to prepare isophthalonitrile(IPN)was studied in a fixed bed reactor.The effects of n(NH_(3))∶n(mx),n(air)∶n(mx),reaction temperature and residence time on the conversion of mx and product distribution were investigated.The reaction paths of gas phase ammoxidation of mx was constructed,and the utilizations of mx(C),O_(2),and NH_(3) along various reaction paths were analyzed under different operating conditions.The experimental results show that the formation of IPN by gas phase ammoxidation of mx is composed of a series of complex parallel-consecutive reactions.Deep oxidation and ammonia combustion consume a large amount of C,O_(2) and NH_(3).Appropriate n(NH_(3))∶n(mx),n(air)∶n(mx),reaction temperature and residence time are conducive to improving the effective utilization rate of raw materials.In addition,the use of a new technology of partition-enhanced reaction can effectively reduce the loss of NH_(3) and O_(2).