Keggin型十二钨磷酸盐@g-C_(3)N_(4)皮克林乳液微反应器促进苯甲醛高效氧化

Keggin-Type Tungstophosphate@G-C_(3)N_(4)Pickering Emulsion Microreactor for Efficient Oxidation of Benzaldehyde

改进设计了一个12学时的综合化学实验。在现行教材Keggin型多酸合成与苯甲醛氧化反应基础上,引入双亲性二维材料g-C_(3)N_(4),构筑Keggin型多酸@皮克林乳液微反应器,通过实验改进促进了苯甲醛氧化反应的高效进行,实现了反应场所的优化设计。同时,Keggin型多酸的选择由十二钼磷酸(H_(3)PMo_(12)O_(40))改进为十二钨磷酸钾(K_(3)PW_(12)O_(40)),利用钨系多酸独特的抗氧化特性,促进催化反应的快速进行。K_(3)PW_(12)O_(40)的合成过程简单、原料绿色易得,避免了易燃溶剂(如乙醚)的使用。双亲性g-C_(3)N_(4)材料具有较大的比表面,亲水基团和共轭骨架结构可以同时吸附多酸分子、过氧化氢分子和苯甲醛分子,促进过氧化氢和苯甲醛的等摩尔比高效快速转化。相较于原教材内容,改进实验更加符合绿色化学“原子经济性”的特点,实验中红外光谱和薄层色谱表征技术的使用,加强了理论学习与实践操作的融合。该实验充分体现了成果导向(OBE)教育理念,以创新型人才培养为目标导向,将学科前沿研究成果引入本科生实验教学,培养化学类大学生的创新意识以及提升他们综合分析、解决问题的能力。

In this work,a 12-h comprehensive chemical experiment was designed.Based on the synthesis of Keggintype polyoxometalate(POM)and the oxidation reaction of benzaldehyde in current textbooks,an amphiphilic twodimensional material,g-C_(3)N_(4),was introduced to construct a Keggin-type POM@Pickering emulsion microreactor,promoting the efficient oxidation of benzaldehyde and optimally designing the reaction site.Different from the original content,the selection of Keggin-type POM was improved from H_(3)PMo_(12)O_(40) to K_(3)PW_(12)O_(40).The unique antioxidant properties of K_(3)PW_(12)O_(40)can promote the catalytic oxidation reaction.Importantly,the synthesis process of K_(3)PW_(12)O_(40)is simple,raw materials are environmentally friendly and easy to obtain,and flammable solvents(such as diethyl ether)are not used.The amphiphilic g-C_(3)N_(4)material with large specific surfaces,the hydrophilic group and conjugated skeleton in its structure,can simultaneously adsorb POM molecules,hydrogen peroxide,and benzaldehyde molecules,promoting the equimolar ratio conversion of hydrogen peroxide and benzaldehyde.The improved experiment is more consistent with the characteristics of“atomic economy”in green chemistry.Moreover,the combination of infrared spectroscopy and thin layer chromatography detection technologies can strengthen the integration of theoretical learning and practical operation.This work embodies the development of outcome based education(OBE)education for the cultivation of creative talents by introducing the frontier research into undergraduate experimental teaching,which is conducive to cultivate innovative consciousness of students and to improve their ability of comprehensive analysis and solving practical problems.