Analysis And Control Of The Impurity Which Influence Acrylonitrile Polymer Outward Appearance

Acrylonitrile is an important monomer for three major synthetic materials(synthetic fibre, Synthetic resin and Synthetic Rubber). Propene ammoxidation method for the synthesis of acrylonitrile is the most mature technology and the most widely used production process in the world currently. The Polyacrylonitrile fiber, acrylonitrile-butadiene-styrene(ABS) resin, styrene-acrylonitrile copolymer(SAN) and acrylonitrile- butadiene rubber(NBR) that produced by Petrochina LanZhou Petrochemical Company have had long-standing problem with yellowish outward appearance. This thesis has expounded and proven that excessive oxazole in acrylonitrile was the basic reason for the problem. GC-MS to identify oxazole peak and a chromatography quantitative analysis method to detect oxazole content were finished. A lot of data about the oxazole content were collected and analysed with changing a large number of important parameters in production process. The experiments showed that temperature of TC-1233 in extractive distillation tower T-104 was the key factor to remove oxazole, which is reasonable technically. The method to reduce oxazole in acrylonitrile and to be quantitative control and the empirical formula to estimate oxazole content in acrylonitrile product were investigated. Finally oxazole content was suppressed lower than threshold successfully and the long-standing problem of yellowish outward appearance of polymer products of own company was solved. The quantification of oxazole content in this study explored the broad application prospects in the similar devices.