Catalyst

Esters and Esterification

TiTAS titanates are understood as Lewis acids suitable for esterification, trans-esterification and polyesterification catalyst usage.

Direct esterification is the reaction between a carboxylic acid and an alcohol to produce an ester plus water as showing below equation. With TiTAS titanates, esterification is conducted at 220˚C efficiently and catalyst is easily removed by water washing out.

In a trans-esterification reaction, a preformed ester exchanges alkoxy group with another alcohol to produce a new ester as below.

Polyesterification is an extension of either or both of the above reactions. Polyesters are produced by the interaction of a dibasic acid or its lower alkyl ester with a glycol or polyol, i.e. by direct or  transesterification reactions.

Advantages of TiTAS Titanates

TiTAS titanates are neutral compounds and it is this neutrality that gives titanates many of their advantages over acidic and basic catalysts. Acids and bases cause side reactions and degradation of the reactants. This leads to poor color and contamination of both the product ester and any excess reactant. TiTAS titanates minimize these side reactions. It is therefore possible to use larger excesses of reactant alcohols, which can be recycled without intermediate purification. This in turn leads to higher conversions and yields of purer products. Effluent treatment is minimized or eliminated.

Other metallo-organic catalysts are available, for example, certain derivatives of tin, magnesium and aluminum. However, it is usually found that these are either more prone than titanates to cause side reactions or are less cost- effective.

Physical Properties

Application Field

TiTAS titanates are the most successful brand in plasticizer industries, but not limited to these. The ranges are also widely used in fatty ester, polyester polyol, polyester including PET and PBT, and polyolefin industries around the world.