改性HZSM-5沸石分子筛对五氧化二氮硝化甲苯的影响  

Effects of Modified HZSM-5 Zeolite Molecular Sieve on the Nitration of Toluene with Dinitrogen Pentoxide

作　　者：洪钟 吕早生 程广斌[2] HONG Zhong;L Zaosheng;CHENG Guangbin(School of Chemical Engineering and Technology,Wuhan University of Science And Technology,Wuhan 430080,China;School of Chemical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China)

机构地区：[1]武汉科技大学化学与化工学院,武汉430081 [2]南京理工大学化工学院,南京210094

出　　处：《应用化学》2020年第6期635-641,共7页Chinese Journal of Applied Chemistry

摘　　要：五氧化二氮(N2O5)作为一种新型绿色硝化剂,可替代传统高污染的混酸,然而N2O5直接硝化收率较低。本文使用3种方法对HZSM-5沸石分子筛Z5进行改性,将催化剂用于N2O5硝化甲苯,并使用吡啶红外(FT-IR)、X射线衍射(XRD)进行表征。实验表明:引入催化剂后,一硝基甲苯收率明显提升,其中浸渍法(IM)改性效果优于离子交换法,Cu-Z5-IM(Z5为HZSM-5沸石)的活性最高,一硝基甲苯产率达到了67.7%,相比未改性(45.2%)提高了22.5%;经过5种不同浓度NaOH改性后,得出0.2 mol/L改性浓度最佳,硝化产率达到了58.5%。Nitrous pentoxide,a new type of green nitrating agent,can replace the traditional highly polluting mixed acid.However,the conversion of direct nitrification by N2O5 is low.In this paper,three methods were used to modify HZSM-5 zeolite molecular sieve.Then,the catalyst was used to nitrate toluene with N2O5,and pyridine Fourier-transform infrared(FT-IR)and X-ray diffraction(XRD)were used for characterization.Experimental results show that the yield of mononitrotoluene is significantly improved after the introduction of the catalyst.Among them,the modification effect of the impregnation method is superior to the ion exchange method.Compared to the unmodified(45.2%),the yield increases by 22.5%;After 5 different concentrations of NaOH modification,it is found that the best modification concentration is 0.2 mol/L,and the nitrification yield reaches 58.5%.

关 键 词：五氧化二氮 HZSM-5 一硝基甲苯 硝酰阳离子 

分 类 号：O625.1[理学—有机化学] O643.3[理学—化学]