Study on the synthesis of dop catalyzed by the composite solid superacid PO_4~(3-)/Ti-La-O

The composite solid superacid PO 4 3- /Ti La O has high catalytic activity on the synthesis of DOP. The conversion of phthalic anhydride is not less than 99% after three hours. The conditions of synthesis of DOP have been studied: the octanol is 140ml, the phthalic anhydride is 30g, the quantity of catalyst is 1.0g, the absorbite is 0.2g, the time of reaction is 4h. The best technology condition has been found. This kind of solid superacid has many advantages, such as being able to use several, recovery very easy, high water resistibility, less corrosion for the equipment and less pollution to the environment.