碱金属催化添加剂对PX液相氧化过程的影响

验证了K+,Na+类添加剂在对二甲苯(PX)液相氧化体系中的助催化活性。对添加不同浓度碱金属离子的助催化作用进行了多组动力学实验,考察了添加K+,Na+对体系主反应和燃烧副反应和TA固体产品中4-CBA含量的影响,获得了对PX氧化过程的影响规律。实验发现,碱金属离子的添加有不同程度的活化效果;添加w(K+)=(30~100)×10-6可有效地加速主反应,但过大时(>500×10-6)作用就变得不明显,甚至会产生抑制;与K+相比,Na+对主反应的助催化活性要低得多。

Effect of alkali metal catalytic additives on p-Xylene liquid phase oxidation

The catalytic activities of K~+,Na~+ alkali metal ions additives in p-xylene liquid phase oxidation system were verified.Multi groups of kinetics experiments were carried out on the catalytic effects of the alkali metal ions under different adding mass fraction.The effect of K~+,Na~+ adding amount on the system main reaction and combustion side reaction,the effects of 4-CBA content in TA solide product were investigated.The effect principles of alkali metal ions additives on PX oxidation process were obtained.The experiments showed that the adding amount of alkali metal ions had different effects on the degree of activity.The main reaction can be accelerated efficiently as the adding mass fraction of K~+ was(30～100)×10~(-6).The cataytic effects were not obviously or even inhibited when the adding amount was so big.Compared with K~+,the catalytic activities of Na~+ on the main reaction was much lower.