Abstract: The ketalization of glycerol with acetone was conducted over an ionic liquid[P(C₄H₉)₃C₁₄H₂₉][TsO] (TTPT) in a batch reactor. A scheme to obtain the purified product using TTPT as a homogeneous catalyst is proposed and a maximum solketal yield of 86% is achieved at acetone/glycerol molar ratio of 6/1, reaction time of 0.5 h, reaction temperature of 303 K, catalyst amount of 5 wt% of glycerol. TTPT was recycled and reused for ten times without obvious losses in terms of quantity and activity. Furthermore, effects of various experimental parameters (stirring speed, catalyst loadings, temperature and reactant composition) on the reaction kinetics are investigated. In terms of kinetics modeling, K_γ is fitted by reactant composition at the temperature range 298 K-323 K, which was a concise strategy that showed good precision in the kinetics fitting. The activation energy for this ketalization reaction was evaluated to be 28.2 kJ·mol^-1. In addition, the kinetics of the reaction at a temperature exceeding the boiling point of acetone were also studied. We believe that all the results are important for further development of a technology for the continuous synthesis of solketal.

Key words: Ionic liquid, Ketalization, Solketal, Glycerol, Reaction kinetics, Reactive distillation

摘要： The ketalization of glycerol with acetone was conducted over an ionic liquid[P(C₄H₉)₃C₁₄H₂₉][TsO] (TTPT) in a batch reactor. A scheme to obtain the purified product using TTPT as a homogeneous catalyst is proposed and a maximum solketal yield of 86% is achieved at acetone/glycerol molar ratio of 6/1, reaction time of 0.5 h, reaction temperature of 303 K, catalyst amount of 5 wt% of glycerol. TTPT was recycled and reused for ten times without obvious losses in terms of quantity and activity. Furthermore, effects of various experimental parameters (stirring speed, catalyst loadings, temperature and reactant composition) on the reaction kinetics are investigated. In terms of kinetics modeling, K_γ is fitted by reactant composition at the temperature range 298 K-323 K, which was a concise strategy that showed good precision in the kinetics fitting. The activation energy for this ketalization reaction was evaluated to be 28.2 kJ·mol^-1. In addition, the kinetics of the reaction at a temperature exceeding the boiling point of acetone were also studied. We believe that all the results are important for further development of a technology for the continuous synthesis of solketal.

关键词: Ionic liquid, Ketalization, Solketal, Glycerol, Reaction kinetics, Reactive distillation