磁性纳米颗粒负载离子液体催化合成聚甲醛二甲醚

摘要

Magnetic nanoparticle supported ionic liquid catalysts were prepared.XRD, TEM and FT-IR were used for the characterization of the catalysts.The results show that ionic liquid was well supported on magnetic nanoparticles.Polyoxymethylene dimethyl ethers (PODEn) was synthesized via the reaction catalyzed by the magnetic nanoparticle supported ionic liquid catalyst.The influences of catalyst dosage, the mole ratio of methanol to trioxane, reaction temperature and reaction time on catalytic activity were investigated.The optimum operating conditions were obtained:reaction temperature 110℃, reaction time 3 h, n (methanol) ∶n (trioxane) =2∶1, catalyst dosage 2.0％.Under these conditions, the conversion rate of trioxane was 99.8％ and selectivity of PODE3～8 reached 37.96％, catalyst still remained highly active even after being reused four times.%制备了磁性纳米颗粒负载离子液体催化剂, 使用XRD、TEM、FT-IR等手段对催化剂进行分析表征, 结果表明离子液体较好地负载在磁性纳米颗粒上.将其用于催化合成聚甲醛二甲醚 (PODEn) 的反应中, 考察了催化剂用量、醇醛比、反应温度和时间等因素对催化活性的影响, 得出了最佳工艺条件:催化剂的质量分数为2.0％, 甲醇与三聚甲醛物质的量比2∶1, 反应温度110℃, 反应时间3h.在该条件下, 三聚甲醛的转化率为99.8％, PODE3～5的选择性达到37.96％, 催化剂重复使用4次后仍有较高催化活性.