"Polyester" refers to in each molecule contains a class of many ester compounds, poly (ethylene terephthalate) (PET) is the most important type of polyester. It is widely used in the production of packaging materials, beverage bottles and textile and clothing products. Polyester catalyst is used in the process of condensation reaction of "PTA/EG - polyester chip", which promotes the condensation reaction and improves the ability of condensation polymerization. There are many kinds of catalysts used in the polymerization of polyester production, and the main catalysts are antimony, germanium and so on. Because antimony catalyst in condensation process can greatly promote the condensation reaction, and the thermal degradation reaction to promote to a lesser extent, so the current polyester industry commonly used antimony based catalysts, the main varieties have ethylene glycol antimony (SB2 (eg) 3), three oxidation antimony trioxide (Sb2O3), antimony acetate and so on.