The Techniques for Analysis of PTA/Coal-based EG Developed by SRIPT Passed Appraisal

Recently the research project “The system for analysis and assessment of polyester and its products” jointly undertaken by the SINOPEC Shanghai Research Institute of Petrochemical Technology (SRIPT), the Yizheng Chemical Fibers Company （YCFC）, and the Donghua University has passed the appraisal of technical achievements organized by the Sinopec Corp.The experts attending the appraisal meeting have recognized that the measurement and analysis methods and control scheme are innovative, and the overall technique has been on a par with the internationally advanced level, while the technology for analysis of pure terephthalic acid (PTA)and coal‐based ethylene glycol (EG) products has reached an international leading level.The experts have proposed to further popularize the application scope of relevant analytical methods, quality standards, and assessment system.

The said project has for the first time developed a high‐efficiency technique for identifying the structure of trace impurities in PTA through combining the super‐high‐efficiency liquid chromatography with high‐resolution mass spectrometry to distinguish several key impurities affecting the chromaticity of PTA and polyester products.The high‐quality PTA quality control scheme formed thereby is applied to the process improvement of PTA production unit at YCFC, which has apparently improved the quality of PTA products to help YCFC crank out the premium optical film and become the number one domestic optical film brand coupled with good economic benefits.

In the meantime this project also uses gas chromatography‐mass spectrometry, liquid chromatography‐mass spectrometry, inductively coupled plasma mass spectrometry (ICP‐MS) and other means to develop the methods for analysis of trace impurities existing in the coal‐based EG to form the scheme for quality control of coal‐based EG, which has been applied in the syngas‐to‐EG unit at the Hubei Chemical Fertilizer Plant, with the product quality conforming to the needs for quality control in polyester production process.