超临界条件下碱性添加物对TS-1催化丙烯环氧化反应的影响  

Effect of Alkaline Additive on Propylene Epoxidation Catalyzed by TS-1 in Supercritical CO_2

作　　者：张耀日[1,2] 吴玉龙[2] 陶玲[2] 杨明德[2] 唐娜[1] 

机构地区：[1]天津科技大学海洋科学与工程学院,天津300222 [2]清华大学核能与新能源技术研究院,北京100084

出　　处：《石油学报（石油加工）》2011年第4期629-633,共5页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：国家自然科学基金项目(20506011);山东省科技攻关计划项目(GG0937b2808010)资助

摘　　要：在超临界CO_2(简称scCO_2)反应介质中,TS-1催化丙烯环氧化制备环氧丙烷(PO)的H_2O_2,转化率,PO选择性和H_2O_2利用率要高于在传统甲醇介质中的,但是仍存在H_2O_2分解和PO选择性较低等不足。系统研究了添加NaOH、NaHCO_3、Urea和(NH_4)_2CO_3碱性组分对TS-1催化内烯环氧化制备环氧内烷反应的影响。结果表明,TS-1催化丙烯环氧化反应体系加入各种碱性组分均可不同程度地提高PO选择性,但加入NaOH和NaHCO_3会使H_2O_2分解加剧,而加入Urea和(NH_4)_2CO_3则能缓解H_2O_2分解,其中(NH_4)_2CO_3的效果最好;反应体系加入0.054mmol的(NH_4)_2CO_3后,H_2O_2转化率、PO选择性和H_2O_2利用率分别达到了97.0%、96.8%和98.2%,从而解决了该反应在scCO_2介质中存在的H_2O_2分解和PO选择性低的问题。The conversion of H2O2, selectivity of propylene oxide （PO） and utilization of H2O2 of propylene epoxidation in supercritical CO2 （scCO2 for short） was higher than that in traditional methanol medium, but there still existed some problems in the epoxidation of propylene catalyzed by TS-1 in scCO2 reaction medium, such as decomposition of H202 and poor selectivity of PO. The effect of four alkaline component （NaOH, NaHCO3 , Urea and （NH4）2CO3） on the epoxidation reaction was systematically investigated. As a result, all the four alkaline components had positive effect on PO selectivity, among which NaOH and NaHCO3 could promote the decomposition of H2O2, while urea and （NH4）2CO3 could decrease the decomposition of H2O2 and increase the selectivity of PO as well, （NH4）2COa got the best result in comparison. The addition of 0. 054 mmol （NH4）2CO3 in the reaction system could raise the conversion of H2O2, selectivity of PO and utilization of H2O2 to 97. 0%, 96. 8% and 98. 2% respectively. So the decomposition of H2O2 and poor selectivity of PO caused by scCO2 can be solved by （NH1）2CO3 additive.

关 键 词：TS—1 丙烯环氧化 碱性添加剂 超临界CO2(scCO2) 

分 类 号：TQ203.2[化学工程—有机化工]