【摘 要】
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Polyoxymethylene dimethyl ethers(PODE)with the formula CH3O(CH2O)nCH3,when n= 3-8,have been considered as the potential diesel additive owing to their highp
【机 构】
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State Key Laboratory for Oxo Synthesis and Selective Oxidation,Lanzhou Institute of Chemical Physics
论文部分内容阅读
Polyoxymethylene dimethyl ethers(PODE)with the formula CH3O(CH2O)nCH3,when n= 3-8,have been considered as the potential diesel additive owing to their highperformance in improving the thermal efficiency and reducing the emission of COx and NOx.Recently,SO3H-functionalized ionic liquids were found show excellent catalytic activity toward the synthesis of PODE from trioxane and methanol.To elucidate the origin of the high catalytic activity of SO3H-functionalized ionic liquids and gain more insight into the chain propagation process of PODE,a mechanistic study has been conducted by performing density functional theory calculations.The calculated results indicate:1)SO3H-functionalized ionic liquids not only play as the acid catalysts,but also stabilize the intermediates formed in the chain propagation process,such as the protonated formaldehyde,carbocation; 2)the reaction proceeds along two pathways,hemiacetal mechanism and carbocation mechanism.
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