新型高负荷苯酐催化剂

通过单管模试装置研究了邻二甲苯氧化制苯酐(PA)高负荷催化剂工艺参数的变化以及催化剂的稳定性。该催化剂在单管风量4 0m3/h、盐浴温度358～360℃的条件下,邻二甲苯质量浓度达85～90g/m3,反应器出口苯酐质量收率111%～113%,粗苯酐中苯酞质量分数不大于0 04%。同时,重复性实验表明,该催化剂具有很好的重复性能。此外,在催化剂开车初期,少量停车次数对催化剂性能无明显影响,高热点温度实验表明,该催化剂具有良好的耐热稳定性。

A New Higher Loading Catalyst for the Oxidation of o-Xylene to Phthalic Anhydride

A new high loading catalyst for phthalic anhydride (PA) from o -xylene was developed.A bench scale catalyst evaluation unit was used to study variation of process parameters and catalyst stability characteristics. Under the conditions of air flow rate 4 0 m 3/h in a single tube,salt bath temperature 358～360 ℃, o -xylene concentration 85～90 g/m 3,yield of phthalic anhydride was 111%～113% in the reactor outlet and phthalide content in crude phthalic anhydride was less then 0 04%.Repeated tests showed the catalyst have good repeatability.At initial start-up stage of catalyst,a few shut-downs have no obvious influence to characteristics of catalyst.High hot spot temperature test showed that the catalyst have good heat-resistant stability.