PTA is mainly used in the production of polyester products, ... ) 20 maxColor (APHA) 10 maxIron (ppm) 0.5 maxPara Toluic Acid (ppm) 120 maxTotal metals Fe, Mn, Co, Cr, Ni, ... 2 maxΔ Y 10 maxb-Color 1.5 max Applications PTA is mainly used in the production of polyester products, including ... container). Bulk container (up to 25MT per 20ft container).-------------------------- PTA (Purified Terephthalic Acid)