固载化ZnCl2催化合成3-甲基-3-丁烯-1-醇

Synthesis of 3-methy-3-buten-1-ol catalyzed by immobilized ZnCl2

    摘要
  • 摘要: 采用碾磨-活化法制备了SiO2-ZnCl2(Silzic)催化剂,并将其用于异丁烯与甲醛Prins缩合合成3-甲基-3-丁烯-1-醇(MBOH)。系统研究了温度、物料比、时间和催化剂的组成及用量对该反应的影响。结果表明,在不同的条件下,甲醛都保持着99%以上的高转化率;然而,不同的条件对MBOH的选择性和收率的影响程度不同,其中,反应温度、催化剂的酸量是影响该反应的关键因素;物料比和反应时间对MBOH的选择性和收率的影响相对较小。实验得到最佳的反应条件为,反应温度210 ℃、二氧六环8 g、三聚甲醛1.5 g、n(异丁烯)/n(三聚甲醛)=7:1、30 mg 1 mmol/g Silzic 和反应时间2 h,在此条件下MBOH的选择性和收率可分别达到93.8%和93.4%。当催化剂循环使用五次时,MBOH的收率降为85.2%,表明该催化剂具有一定的重复使用性。

     

    Abstract: Immobilized ZnCl2 (Silzic) catalyst was prepared and used in the synthesis of 3-methyl-3-buten-1-ol (MBOH) from isobutylene and formaldehyde; the effects of the reaction parameters, such as temperature, molar ratio of isobutene to formaldehyde, reaction time and catalyst content on the reaction behavior were investigated. The results showed that the conversion of formaldehyde is over 99% under various conditions. The reaction temperature as well as the catalyst acidity and the amount of the acid sites are dominant factors in influencing the selectivity to MBOH. Under the optimum reaction conditions, i.e. 210 ℃, 8 g 1,4-dioxane, 1.5 g polyoxymethylene, n(isobutylene)/n(polyoxymethylene) ratio of 7, 30 mg Silzic (1 mmol/g), and reaction time of 2 h, the selectivity and yield of MBOH reach 93.8% and 93.4%, respectively. The Silzic catalyst exhibits certain reusability; the yield of MBOH remains 85.2% after reusing the catalyst for 5 times.

     

    • HTML全文
    • 参考文献(24)
    • 相关文章
    • 施引文献
  • 资源附件(0)

/

返回文章
返回