基于硫酸介质的乙二醛常压氧气氧化制备尿囊素  

PREPARATION OF ALLANTOIN FROM GLYOXAL BY ATMOSPHERIC OXYGEN OXIDATION WITH SULFURIC ACID AS A MEDIUM

作　　者：王晓冰[1] 郭瓦力[1] 李萍[1] 邓信忠[1] 戴玺[1] 朱虹[1] 李磊[1] 单译[1] 

机构地区：[1]沈阳化工大学化学工程学院,辽宁沈阳110142

出　　处：《精细石油化工》2013年第1期67-70,共4页Speciality Petrochemicals

摘　　要：研究了以硫酸和氯化铝为酸性介质,亚硝酸钠为催化剂,常压氧气氧化乙二醛制备乙醛酸,进而在不添加酸性催化剂的条件下直接合成尿囊素的技术路线。通过对各影响因素的考察确定了氧化反应适宜的工艺条件为:乙二醛质量分数25%,钠醛比0.2、酸醛比0.4、反应温度25℃、反应时间3h,在此条件下,乙醛酸收率为76.12%;缩合反应适宜的工艺条件为:乙醛酸尿素投料比1∶4,反应温度75℃,反应时间3h,此时尿囊素的收率可达60.75%。The technical route of allantoin synthesis was studied, which was characterized with the glyoxylic acid preparation by oxygen oxidation of glyoxal at ambient pressure with sulfuric acid and a- luminum chloride as acid medium, and sodium nitrite as catalyst first, then direct synthesis of allanto- in without the addition of acid catalyst. The suitable process conditions for the oxidation were deter- mined after investigation of affecting factors, that is, mass concentration of glyoxal was 25%, the molar ratio of sodium nitrite to glyoxal was 0.2, molar ratio of sulfuric acid to glyoxal was 0.4, reac- tion temperature was 25 ℃ and reaction time was 3 h. Under these conditions, the yield of glyoxylic acid was up to 76.12%. The suitable conditions for condensation reaction were as follows： the molar ratio of glyoxylic acid to urea was 1 ： 4, reaction temperature was 75 ℃and reaction time was 3 h. Under these conditions, the yield of allantoin was up to 60.75%.

关 键 词：乙二醛 氧气 乙醛酸 尿囊素 

分 类 号：TQ203.5[化学工程—有机化工]