负载型MgO/SiO_2催化合成羟基特戊酸新戊二醇单酯

以工业甲醛和异丁醛为原料,通过羟醛缩合、负载型MgO/SiO2催化歧化反应两步合成了羟基特戊酸新戊二醇单酯。对歧化反应中的反应温度、反应时间、催化剂用量进行了探讨,得到的歧化反应的最佳工艺条件为:反应温度90℃,反应时间90min,催化剂用量为2,2-二甲基-3-羟基丙醛(HPA)质量的3%。歧化反应中HPA转化率达90%以上,产品选择性达97%以上。粗产品经减压精馏,纯度达到99%,产品过程总收率达到80%以上。反应后催化剂经过滤即可分离回收利用,重复利用4次后,负载催化剂活性变化不明显,采用比表面积检测法(BET)和扫描电子显微镜对催化剂进行了表征,结果表明其催化性能稳定,可多次重复使用。

Synthesis of Hydroxypivalic Acid Neopentyl Glycol Monoesters Catalyzed by Supported MgO/SiO2

Using supported MgO/SiO2 as catalyst,the synthesis of hydroxypivalic acid neopentyl glycol monoesters(HPN) from industrial formaldehyde and isobutyraldehyde was studied.The effect of reaction temperature,reaction time and dosage of catalyst were investigated.The optimum conditions were obtained as follows: reaction temperature 90 ℃,reaction time 90 min,dosage of catalyst 3% of 2,2-dimethyl-3-hydroxy propionaldehyde(HPA).Under these conditions,the conversion of HPA reached 90%,and the selectivity of HPN reached 97%.The purity of the product reached 99% after vacuum distillation.The total yield of HPN was 80%.The supported MgO/SiO2 catalyst could easily be filt after the reaction.The supported catalysts were characterized by BET and SEM,and the results showed that the supported MgO/SiO2 catalyst could be reused up to 4 times with no apparent decrease in the conversion of HPA and yield of HPN.