Synthesis and performance of piperidinium-based ionic liquids as catalyst for alkylation of p-xylene with 1-hexadecene
作者:Ge, SJ (Ge, Sujuan) [1] ; Zhou, YM (Zhou, Yuming) [1] ; Sheng, XL (Sheng, Xiaoli) [1] ; Mao, CF (Ma
关键字:alkylationpiperidinium-based ionic liquidsreaction performancerecyclability
论文来源:期刊
发表时间:2021年
Piperidinium-based ionic liquids (ILs) were synthesized under mild conditions by coordinating N-alkyl-N-methylpiperidinium bromide ([Pip(1,x)]Br) with anhydrous AlCl3. The weak basicity of N-methylpiperidine had little impact on downstream problems from proton impurities and catalyst poisoning. The results of Fourier transform infrared (FT-IR), electrospray ionization mass spectrometry (ESI-MS), and nuclear magnetic resonance (Al-27 NMR) confirmed that the active components in [Pip(1,x)]Br-2AlCl(3) (chi = 0.67) were [Al3Cl9Br](-) and [Al2Cl6Br](-). Besides, the reaction performance of [Pip(1,8)]Br-2AlCl(3) under different conditions was carried out by single-factor experiment and further confirmed by orthogonal experimental method. Among these reaction conditions, the optimal combination was the reaction temperature of 40 degrees C, ILs/O molar ratio of 0.2:1, px/O molar ratio of 12:1, and the reaction time of 30 min. Furthermore, [Pip(1,8)]Br-2AlCl(3) had excellent stability and can be recycled 14 times. It was the high-efficiency catalytic activity and prominent recyclability that made continuous industrial production possible.