氢氧化四乙基铵对Hβ沸石脱硅过程的影响  

Effect of Tetraethylammonium Hydroxide on Desilication of Hβ Zeolite with NaOH Solution

作　　者：周志伟[1] 秦娟[2] 武文良[1] 徐卫敏[1] 火焱 

机构地区：[1]南京工业大学化学化工学院,江苏南京210009 [2]江苏省生产力促进中心项目管理部,江苏南京210042

出　　处：《石油化工》2010年第10期1115-1121,共7页Petrochemical Technology

基　　金：江苏省高校自然科学重大基础研究项目(07KJA53013)

摘　　要：采用NaOH溶液对Hβ沸石进行脱硅处理,制备了一系列不同硅铝比的脱硅Hβ沸石,考察了模板剂氧氧化四乙基铵(TEAOH)对脱硅过程的影响及脱硅Hβ沸石在甲苯与叔丁醇烷基化反应中的催化性能。采用ICP、XRD、NH_3-TPD、FTIR、N_2吸附和^(29)Si MAS NMR等手段对脱硅Hβ沸石进行了表征。表征结果显示,脱硅Hβ沸石存在部分介孔结构;TEAOH的存在能有效保护Hβ沸石的骨架结构,提高Hβ沸石晶体的结晶度。当c(NaOH)=0.03 mol/L时,对含TEAOH的Hβ沸石进行处理制备的Hβ0(0.03)沸石的酸量最大,催化活性最高。以Hβ0(0.03)沸石为催化剂,在反应温度180℃、反应时间4h、n(甲苯):n(叔丁醇):n(正己烷)=1:3:10、m(甲苯):m(催化剂)=8时,甲苯转化率为65.7%,叔丁基甲苯选择性为98.4%,对叔丁基甲苯选择性为75.8%。Desilicated Hβ zeolites were prepared through treatment of Hβ zeolite with NaOH aqueous solution. Influence of template tetraethylammonium hydroxide （TEAOH） on the desilication was investigated. The desilicated Hβ zeolites were characterized by means of ICP, XRD, NH3-TPD, FTIR, liquid N2 adsorption-desorption and 29Si MAS NMR. Their catalytic performances in alkylation of toluene with tert-butyl alcohol into ten-butyl-toluene were studied. The results showed that there was mesoporous structure in the desilicated Hβ zeolites. TEAOH could protect skeletal structure of the desilicated Hβ zeolites and heighten their relative crystallinity. Hβ0 （0. 03 ） zeolite treated with 0.03 mol/L aqueous NaOH solution in the presence of TEAOH showed higher catalytic activity in the alkylation than those of other Hβ zeolites because of its high acid amount. Conversion of toluene 65.7%, selectivity to ten-butyl-toluene 98.4% and selectivity to p-tert-butyl-toluene 75.8% were reached under the conditions of Hβ0 （ 0. 03 ） zeolite as catalyst, reaction temperature 180℃, n（toluene） ： n（ten-butyl alcohol） ： n（n-hexane） 1 ： 3 ： 10, m（toluene） ： m（catalyst） 8 and reaction time 4 h.

关 键 词：甲苯 叔丁醇 烷基化催化剂 氢氧化四乙基铵模板剂 脱硅Hβ沸石 对叔丁基甲苯 

分 类 号：TQ255[化学工程—有机化工]