| Rosin ester if icat ion is one of the most fundamental means in rosin modification .At present ,all kinds of rosin ester ified products account for over 60% in rosin modified products , and rosin glyceride is a kind of rosin esterified product which is most widely used , it is used in dope, furniture,printing ink.rubber .coherent agent and so on . It is a very important chemical product in national economy . ZnO is the best catalyst to produce rosin glycercide in industry. However, the catalytic activity of ZnO is not very high and it is very difficult to separate from products. Therefore , deve I op i ng a k i nd of cata I yst which has high activity and is not dissolve in rosin glyceride is very necessary .In this paper , advanced nano-techno I ogy has been applied to catalytic preparation .high activity and nonhomogeneous solid superacid catalyst used in rosin esterifed reaction has been developed , and the craftwork and mechanism of rosin esterification and the structure and property of the catalyst have been researched. The whole process is divided into five parts which are as follows:1)The examination of catalytic preparation and property. We have examined the catalytic kinds, preparative methods and preparative conditions, and have found that SO42-/TiO2-SiO2 solid superacid catalyst prepared by sol-gel method has the highest activity. By orthogonal experiments, we have educed SO42-/Ti02-Si02 catalytic best preparative conditions : the mole proportion of TiO2 and Si02 is A4, vitriolic concentration is B2 mol/L, the baking temperature is C2C and the baking time is D2 h. The mole proportion of Ti02 and Si 02 is the maximal influencing factor for catalytic activity of catalysts .2) The discussion of rosin glyceride's preparation. By examining the preparative craftwork of rosin glyceride and orthogonal experiments, we have educed the best preparative conditions of rosin glyceride: the mole proportion of rosin and glycerol is 2:1, reactive temperature is 270C, reactive time is 1h and the dosage of catalyst is 0.75%. The mole proportion of rosin and glycerol is the maximal influencing factor for reactive velocity.3)We have investigated catalytic physical properties by some analytical methods, such as TEM, SEM, XRD and so on. Then we have drawn a conclusion: the size of the particles of SO42-/TiO2-SiO2 solid superacid catalyst is 10nm. The maximal acid strength is -14.5. The stronger the catalyt ic acid strength i s, the higer the catalytic act ivity is. Noncrystal Ti02 or Noncrystal Si02 can not get sol id superacid catalyst. The acid centre model of SO42-/TiO2-SiO2 is chelate structure.4)By discussing the mechanism of catalytic losing activity ,we have cone I uded that the ma i n I os i ng act i v i ty reason of so I i d superac i d cata I ysts used in ester if ied reaction between rosin and glycerol is the accumulated carbon of catalytic surface.5)By primarily researching the mechanism of the ester ified reaction between rosin and glycerol, we have drawn a conclusion :when the mole proport i on of ros i n and g I ycero I i s d i f f erent , i ts react i ve k i net i c mod I e is different. When the mole proportion of Ti02 and Si02 is less than 3, the reaction of rosin ester ification is a zero-grade reaction; when the mole proportion of TiO2 and Si02 is not less than 3, the reaction of rosin ester ification is a two-grade reaction, its kinetic equation is r=kc2glycarol, the relationship between balanceable constant, and temperature is:Lnk=-1948. 5/T-O. 62, the activation energy E.= 162KJ.mol-1. |
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