摘要
对2,4-二氯甲苯经氨氧化法,一步制备有机中间体2,4-二氯苯腈进行了研究.在“微反-色谱”联用装置上完成催化剂的评比和筛选后,在内径30mm的石英管固定床反应器上印证并进行工艺条件实验.考察了反应温度、氨比、空气比和空速对反应的转化率、摩尔收率和选择性的影响.所确定的工艺简捷,在合适的条件下使用DT124号催化剂,转化率高达98.1%、摩尔收率89.5%,生成2,4-二氯苯腈为白色针状或片状结晶,纯度高于99%.同时,结合2,6-二氯甲苯氨氧化反应研究工作,对二氯甲苯的2、4位和2。
A process for ammoxidation of 2,4 dichlorotoluene to prepare 2,4 dichlorobenzonitrile which is a key intermediate of organic synthesis was studied. Having appraised and screened catalysts on an apparatus of “microreactor chromatograghy”, the further experiments confirming the catalyst and finding the optimum technological conditions were carried out by using a fixed bed reactor made of quartz (30 mm inside diameter). The influence of temperature, the ratio of ammonia, the ratio of air and the space velocity of catalyst upon the conversion, molar yield and selectivity of the reaction were observed, respectively. Using catalyst of DC124, on the suitable conditions, the highest conversion is 98.1%, molar yield is 89.5%. The 2,4 dichlorobenzonitrile obtained is white sheet or needle crystal with the purity higher than 99%. The effect of two chlorine atoms at 2,6 or 2,4 position on the reaction is discussed based on the research of the ammoxidation of 2,6 dichlorotoluene and 2,4 dichlorotoluene.
出处
《武汉大学学报(自然科学版)》
CSCD
1999年第2期177-180,共4页
Journal of Wuhan University(Natural Science Edition)
关键词
氨氧化
二氯甲苯
二氯苯腈
制备
ammoxidation
2,4 dichlorotoluene
2,4 dichlorobenzonitrile