Research On Esterification Catalysted By Room Temperature Ionic Liquid

In modern chemical engineering manufacture, most of chemical reactions need catalyst. Catalyst choice and applications are the key techniques in the chemical engineering process. Developing new green catalyst is a heal research area now.Room temperature ionic liquid is a kind of liquid catalyst material that appears just in the last few years. As a substitute of volatility organic solvents, room temperature ionic liquids are attracting more scientists' attention. The main advantage of the ionic liquid lies in green environment and the plasticity of the structure. We can change its cation and anion to synthesize special catalyst for certain reaction.In this paper, we study the applications of some BrΦnstod acidic ionic liquid in esterificat ion reaction start from the function of ionic liquid. Some new ionic liquids, [Hmim]GS0₄,, [Hmim]₂SO₄, [Hmim]H₂PO₄, [Hmim]₄PO₄,, [Hnmp]HSO₄ , [Hnmp]H₂PO₄, [Hnmp]BF₄, [Hmim]BF₄, are synthesized and some of their properties are measured. [Hnmp] HSO₄ is water-solubility, density 1. 4055g/L, viscidity 2. 451 Pa. s (25℃ ) . Taking the esterifieation reaction of n-butyl acetate as model reaction, we studied the catalyst activity of the 10 ionic liquids which were synthesized first time by us, and find that the catalyst activity of [Hnmp]HSO₄, is very good, even better than that of H₂SO₄, Then we investigate the reaction temperature, time and catalyst quantity of esterification reaction. We find that the main factors which influence the reaction are temperature, time and catalyst, quantity. The orthogonal experiment were done, the result shows that the producing rate of reaction is the highest when reaction time is 3h, temperature is 96℃ and catalyst quantity is 0. 5% (mol % ) . We also studied the recycle ability of catalyst and find out that its catalytic activity is constant alter used 6 times. At last, in order to study the catalyst activity of these catalyst further, we research the esterification of ethanol, l-propanol , benzalcohol , n-heptanol, l-octanol,cyclohexanol with aceticacid, and find...