Novel polymeric acidic ionic liquids as green catalysts for the preparation of polyoxymethylene dimethyl ethers from the acetalation of methylal with trioxane

Heyuan Song; Fuxiang Jin; Meirong Kang; Jing Chen

doi:10.1039/c9ra07765k

Novel polymeric acidic ionic liquids as green catalysts for the preparation of polyoxymethylene dimethyl ethers from the acetalation of methylal with trioxane

RSC Adv. 2019 Dec 9;9(69):40662-40669. doi: 10.1039/c9ra07765k. eCollection 2019 Dec 3.

Authors

Heyuan Song¹, Fuxiang Jin¹, Meirong Kang¹, Jing Chen¹

Affiliation

¹ State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences Lanzhou 730000 China chenj@licp.cas.cn +86-931-4968129 +86-931-4968068.

Abstract

A series of micro-mesoporous polymeric acidic ionic liquids (PAILs) have been successfully synthesized and subsequently characterized using Fourier transform-infrared spectroscopy, N₂ adsorption-desorption isotherms, scanning electron microscopy and thermogravimetry. Furthermore, the catalytic performance of the synthesized PAILs was investigated for the acetalation of methylal (DMM₁) with 1,3,5-trioxane (TOX), micro-mesoporous PAILs copolymerized by divinylbenzene with cations and anions exhibited moderate to excellent catalytic activities for the acetalation. In particular, VIMBs-AMPs-DVB, with higher specific surface area (25.51 m² g^-1) and total pore volume (0.15 cm³ g^-1) displayed an elevated conversion of formaldehyde (82.2%) and selectivity for polyoxymethylene dimethyl ethers (CH₃O(CH₂O) _n CH₃; PODE _n or DMM _n ) n = 3-8 (52.6%) at 130 °C, 3.0 MPa for 8 h. Moreover, the influence of various reaction parameters was investigated by employing VIMBs-AMPs-DVB as the catalyst and it demonstrated high thermal stability and easy recovery.