简介:以2-氯-2-氯甲基-4-氰基丁醛(CCC)为原料,采用三光气作为氯化剂,通过环合反应合成了2-氯-5-氯甲基吡啶。通过单因素实验和正交优化实验确定了环合反应的工艺条件,并对环合反应的机理进行了探讨。优化后的反应条件为:以甲苯为反应溶剂,反应温度为90℃,物料滴加时间为2h,n(CCC)∶n(三光气)∶n(DMF)=1∶0.35∶0.9,采用滴加三光气甲苯溶液的方式投料。在优化工艺条件下,反应收率为86.2%,纯度为99.2%,反应收率高于三氯氧磷工艺15%以上,废水减少80%以上,废固减少30%以上,是一条适合工业生产的工艺路线。
简介:TheinfluenceofmischmetaladditiononphysicochemicalpropertiesofPtSnNa/ZSM-5catalystwasstudiedbymeansofXRF,H2chemisorption,XRD,TPR,NH3-TPDandTPOtechniques.TheresultsshowedthatthepresenceofmischmetalhadanobviousimpactonthecatalyticperformanceofthePtSnNa/ZSM-5catalyst.AsuitablecontentofmischmetalnotonlycouldenhancetheinteractionsbetweenPtspeciesandthesupport,butalsoinhibittheformationofcokeduringthereaction,thusimprovingthecatalyticactivityandstability.Inourexperiments,whenthecontentofmischmetalwas3m%,thecatalystexhibitedbestcatalyticperformance.However,thecontinuousadditionofmischmetalcouldpromotethereductionofSnspeciestometallictin,whichwasdisadvantageoustothereaction.