Study On Process Technology For Production Of High Reactivity Polyisobutene

High reactivity polyisobutene has wide use in many fields, such as lubricant and fuel additives, emulsive explosives, surfactants, detergents and anti-rust agent etc. Jilin Petrochemical Branch Company in China National Petroleum Corporation has possessed their own proprietary technology in producing high reactivity poly-isobutene products and has already set up two industrial plants for producing high reactivity poly-isobutylene. The production capacity of each plant was up to 20000t/a, which shared 90% of the gross domestic market. The development and improvement for this technique possessed great importance and potential application prospect.In this paper, the continuous cationic polymerization was performed over a boron tri-fluoride catalyst at low-temperature from small scale, large scale to industrial scale. Polymer grade isobutylene was used as raw material in order to produce high reactivity poly-isobutylene. The experiment results from the small scale and large scale indicated that the optimized process parameters for producing polyisobutene with 1000 of molecular weight were as follows:the concentration of isobutene in isobutene/hexane mixture feed was 23～45%,0.2～0.8% of catalyst load,-30℃～-5℃of the reaction temperature,0.1～0.3Mpa of the reaction pressure and 25～30 minutes of reaction time. Under these reaction conditions, the terminate olefin content of the obtained polyisobutene was 60%-85%. In addition, the small scale and large scale can provide the products with the same quality if the process parameters are the same. This will lay the fundation for the later scale-up. The industrial apparatus employs the distiguished polymerization process, that is, continuous twin autoclaves and external cycle operation. The process insures the reaction stablility, easy controlling and good products quality.