辽宁师范大学学报(自然科学版)
遼寧師範大學學報(自然科學版)
료녕사범대학학보(자연과학판)
JOURNAL OF LIAONING NORMAL UNIVERSITY(NATURAL SCIENCE)
2013年
3期
365-368
,共4页
苯乙烯%环氧苯乙烷%过氧化氢%Li/MgO%环氧化
苯乙烯%環氧苯乙烷%過氧化氫%Li/MgO%環氧化
분을희%배양분을완%과양화경%Li/MgO%배양화
styrene%styrene oxide%hydrogen peroxide%lithium ion doped magnesium oxide%epoxidation
以H2 O2为氧源,乙腈为溶剂,考察了Li掺杂M gO ,Li/M gO ,对苯乙烯环氧化反应的影响.并用X射线衍射、热重(TG)、扫描电子显微镜(SEM )和CO2程序升温脱附(CO2-TPD)对Li/MgO进行了表征.结果表明,随Li量增加(1%~5%),苯乙烯转化率和环氧化物选择性增加.5% Li/M gO ,苯乙烯转化率达99.5%,环氧苯乙烷选择性为95.9%.增加Li量至11%,Li/M gO的活性和选择性基本不变.这主要归于Li/M gO碱的强度和强碱位数目的变化.
以H2 O2為氧源,乙腈為溶劑,攷察瞭Li摻雜M gO ,Li/M gO ,對苯乙烯環氧化反應的影響.併用X射線衍射、熱重(TG)、掃描電子顯微鏡(SEM )和CO2程序升溫脫附(CO2-TPD)對Li/MgO進行瞭錶徵.結果錶明,隨Li量增加(1%~5%),苯乙烯轉化率和環氧化物選擇性增加.5% Li/M gO ,苯乙烯轉化率達99.5%,環氧苯乙烷選擇性為95.9%.增加Li量至11%,Li/M gO的活性和選擇性基本不變.這主要歸于Li/M gO堿的彊度和彊堿位數目的變化.
이H2 O2위양원,을정위용제,고찰료Li참잡M gO ,Li/M gO ,대분을희배양화반응적영향.병용X사선연사、열중(TG)、소묘전자현미경(SEM )화CO2정서승온탈부(CO2-TPD)대Li/MgO진행료표정.결과표명,수Li량증가(1%~5%),분을희전화솔화배양화물선택성증가.5% Li/M gO ,분을희전화솔체99.5%,배양분을완선택성위95.9%.증가Li량지11%,Li/M gO적활성화선택성기본불변.저주요귀우Li/M gO감적강도화강감위수목적변화.
The effect of the Li addition to MgO on the styrene epoxidation was studied for H 2 O2 as an oxidant in the presence of acetonitrile .The physicochemical properties of the promoted MgO ,Li/MgO ,were investigated with SEM ,TG ,XRD ,and CO2-TPD techniques .The results indicated that with increasing the amount of Li from 1% to 5% ,styrene conversion and selectivity to styrene oxide gradually increase .Using 5% Li/MgO ,the activity and selectivity can be up to 99 .5% and 95 .9% ,re-spectively .Further increase in the amount of Li ,the activity and selectivity over Li/M gO basically re-mained unchanged .These results can be related to the high basicity strength and the amount of strong basic sites on Li/M gO catalysts .