微波辐射改性可膨胀石墨催化合成苯甲醛乙二醇缩醛

以改性可膨胀石墨为催化剂,微波辐射下制备了苯甲醛乙二醇缩醛。通过正交实验考察了合成苯甲醛乙二醇缩醛的影响因素。结果表明,当n(苯甲醛)∶n(乙二醇)=1∶2.5,催化剂占反应物总质量的2.04%,微波辐射功率300 W,辐射时间20 min,带水剂环己烷6 mL时,缩醛的收率可达87.6%;并且催化剂重复使用4次后活性基本不变。通过对催化剂进行SEM和XRD测试表明,H2SO4分子已插入到石墨层中形成层间化合物。

Synthesis of Benzaldehyde Glycol Acetal by the Modified Expandable Graphite under Microwave Irradiation

Expandable graphite modified under microwave irradiation was prepared and then used as catalyst in the synthesis of benzaldehyde glycol acetal.The influencing factors in the synthesis process were investigated through orthogonal experiment.The optimum conditions were as follows: molar ratio of benzyladehyde to glycol 1∶2.5,mass ratio of the catalyst to the total reactants 2.04%,microwave irradiation power 300 W,irradiation time 20.0 min,and the amount of cyclohexane was 6 mL.Under such optimum conditions,the yield of acetal reached 87.6%,and the activity of the catalyst remained basically unchanged after being used for 4 times.The catalyst was studied by SEM and XRD,and the results show that an interlayer compound was instituted by sulfuric acid molecules inserted into the graphite′s layers.