气液固三相催化氧化对二甲苯制对苯二甲酸

为进一步提高对二甲苯液相催化氧化制对苯二甲酸的反应速率和产率,对MC催化体系(Co-Mn/Br)展开了改良研究,考察了对羟基邻苯二甲酰亚胺(NHPI)、甲乙酮(MEK)引发剂和Zr4+、Cu2+金属离子助剂对MC催化体系性能的影响。结果表明,NHPI和MEK引发剂的添加能进一步提高MC催化剂的活性,而Zr4+对MC催化剂性能的影响不大,Cu2+对MC催化剂催化氧化对二甲苯反应有抑制作用。NHPI和Br-双引发剂之间存在协同作用,可以明显提高催化反应活性,降低整个反应体系的温度,是一种有效的MC催化剂改良方法。

Optimization of MC catalysts in selective catalytic oxidation of PX to PTA

The influence of initiator and metal ions additives on performance of Co-Mn /Br catalyst system（ MC） in selective oxidation of p-xylene（ PX） to terephthalic acid（ PTA） was investigated for improvement of reaction rate. The results show that the introduction of N-hydroxyphthalimides（ NHPI） and butanone（ MEK） into MC catalyst as the second initiator improves the activity of the catalyst,while Zr4 ＋has little impact on activity,Cu2 ＋has adverse effect on activity. Comparing with traditional MC catalytic system,the dual initiators＇ catalyst,containing NHPI and Br-,shows better performance of higher catalytic activity at low reaction temperature.