Study On The Reactor For Synthesis Of Antioxidant 1010 Based On Chemical Reaction Engineering

Pentaerythrityl tetrakis-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (antioxidant 1010) is one of the most excellent main antioxidant of polyolefine, which is usually produced by transesterifying a lower alkyl 3-(3,5-di-tert-butyl-4-hydroxyphenl ) propionate with pentaerythritol. The device of Ningbo Jinhai Albemarle Chemical and Industry Co., Ltd., used to synthesize antioxidant 1010 by two-step method using organo-tin compounds as catalyst, has a low inventory rating and a large power consumption so as to have a poor economic performance. And that become a problem to be urgently solved.In this paper, the equations of reaction kinetics were obtained based on the study on the experiment of thermal model. Pitched turbine impeller was chosen as the preferred impeller of the device by the cold model experiment in which the power and the mixing effect of anchor impeller, pitched turbine impeller and turbine impeller were evaluated. From the viewpoint of chemical reaction engineering, a commercial test was also carried out to find out the regularity of the transesterification reaction of synthesis of antioxidant 1010. The result will provide a fundamental basis for industrial design.Firstly, based on the assumptions that the reaction generating mono-ester was controlled by the solution rate of pentaerythritol, that di-ester conversed to tri-ester rapidly and that all the reverse reactions and side reactions were omitted, the equations of reaction kinetics were obtained. At the same time, rate constants at different temperatures and the data of activation energy and pre-exponential factor were determined.Secondly, pitched turbine impeller was chosen as the preferred impeller of the device by the cold model experiment based on the evaluation criterion of energy conservation and mixing effect of the axial direction. According to the same evaluation criterion, the main structure and dimension of the present agitated batch reactor werechecked and redesigned. The same result as above was obtained.Finally, the drawbacks of the present device were a low inventory rating and a large power consumption, against which a commercial test increasing the inventory rating and slowing down the speed of agitator was carried out. From the viewpoint of chemical reaction engineering, the conclusion that it is necessary to increase the area of heat transmission and to improve the agitation condition in order to obtain the expectative content of antioxidant 1010 within the specified time was drew. And the wrong viewpoint that agitation is the only reason determining the reaction effective was corrected.