Purified Terephthalic Acid
Purified terephthalic acid, often known simply as PTA, is in high demand as the key raw material for the manufacture of polyester fiber, resin and film. Two proposed ASTM standards are currently being developed that will be used to find major impurities in PTA product.
The two proposed standards are WK36121, Test Method for Determination of p-Toluic Acid and 4-Carboxybenzaldehyde in Purified Terephthalic Acid by High Performance Liquid Chromatography; and, WK36122, Test Method for Determination of p-Toluic Acid and 4-Carboxybenzaldehyde in Purified Terephthalic Acid by High Performance Capillary Electrophoresis. Both proposed standards are being developed by Subcommittee D16.02 on Oxygenated Aromatics, part of ASTM International Committee D16 on Aromatic Hydrocarbons and Related Chemicals.
According to Yuhong Zhang, an analytical technical specialist at the China Petrochemical Corp., and chair, D16.02, there are several reasons for the development of WK36121 and WK36122:
- Global supply, demand and trade for PTA is very strong and will continue to be throughout the next decade.
- 4-carboxybenzaldehyde and p-Toluic acid are the two major impurities in PTA product and need to be well-controlled.
- Current lack of international standards has caused inconvenience and high testing costs in PTA trade.
“The two proposed test methods will be used by PTA producers for quality control,” says Zhang. “Global adoption of the proposed standard will facilitate world trade and diminish technical barriers.”
All interested parties are encouraged to join Committee D16 in its standards developing activities.
CONTACT Technical Information: Yuhong Zhang, China Petrochemical Corp. • Shanghai, China • Phone: 86-21-68462281 | ASTM Staff: Christine DeJong • Phone: 610-832-9736 | Upcoming Meeting: Jan. 30-31, 2013 • January Committee Week • Jacksonville, Fla.