Solid Superacid In The Rosin Esterification Deactivation And Regeneration Research

Rosin esterification is one of the most fundamental and important means inrosin modification. Rosinglyceride is a kind of rosin esterified product which is most widely used and is a very important chemical product in national economy. Solid superacid catalyst SO₄^2-/TiO₂-SiO₂ has more higher activity in rosin esterification reaction. The catalyst has simple and convenient preparation methods and alow catalyzing temperature along with many avantages such as not eroding metal, friendly to environment and high acid strength. But with the present research going on, the researchers have found out that although the catalyst has high activities, it also has a fast deactivation rate. Enhancing catalyst activities and life-span and seeking catalyst regeneration methods is importantly meaningful to chemical production. The whole research is divided into five parts which are as follows: (1)The Rosin esterification researchOn the base of our lab correlative research, the research has examined many factor respectively and educed the better preparative conditions of rosinglyceride: solid superacid catalyst is SO₄^2-/TiO₂-SiO₂, temperature i s 280℃, the mole proportion of rosin and glycerol is 0.75:1, and reactive time is 1h, the dosage of catalyst is 1.75% (2)The research of the deactivation causes of solid superacid catalyst The research has investigated catalytic physical properties by some analytical methods, such as IR, XRD, BET , TPD and so on. With contrast analyse and validating experimentation, the research has found out the deactivation cause of solid superacid catalyst is the decrease of solid superacid quantity viz. active center amounts induced by the accumulated carbon on catalyst, loss of active component and agglomeration. Among these factors, the accumulated carbon on catalyst has the most important influence on the deactivation of solid superacid catalyst and loss of active component takes second place. Moreover the deactivation catalyst induced by agglomeration can't be regenerated.(3)The research of prolonging catalyst life-spanOn the base of above-mentioned research, the reaserch has examined many factor respectively and used orthogonal experiments. By these experiments, we have educed the best reaction conditions of rosin glyceride for prolonging catalyst life-span: temperature is 290°C, the mole proportion of rosin and glycerol is 0. 75:1, and reactive time is 1. 5h, the dosage of catalyst is 1.75%. Under these conditions, the catalyst I ife-span can react 10 times, and the I ife-span is two times of that under the better preparative conditions of rosin glyceride (5 times). (4)the research of regeneration method of deactivation solid superacidThe research has used different regeneration methods to examine the deactivation solid superacid catalyst. Moreover the research has investigated catalytic physical properties by some analytical methods, such as IR, XRD, BET and so on. With contrast analyse and, the research has found out the best regenerat i on method: f i rst I y, bak i ng cata I yst under 500°C with 1h so as to recover active positions covered by accumulated carbon. Secondly, putting the catalyst in 1.5mol/L vitriolic solution with 2h. After this, taking the catalyst out of and dry it. Finaly baking catalyst under 400°C with 2h so as to make active positions formed on the catalyst. All of these make the deactivation catalyst into the regenerat i on one. The best generat i on cata I yst I i f e-span can react 7 t i mes and has favorable activity and stability...