Study on the peroxidation of cumene catalyzed by metal-chelated copolymer

In this work, metal(II) coordinated with copoly(2-methylacrylic acid 3-(bis-carboxymethylamino)-2-hydroxy-propyl ester-styrene-acrylnitrile- divinylbenzene) was synthesized and used as a catalyst for cumene peroxidation. The fractions of chelating groups in all the copolymer supports were ranged from 6.7 to 10.4 mol% from elemental analysis, whereas the metal chelating capacity for Co(II), Cu(II), Ce(II), and Mn(II) were located at 0.46 and 0.94 meq/g from the ICP detection. According to BET measurements, the surface areas of the polymer support were in the range from 0.02467 to 0.9700 m²/g, sufficient to provide reaction sites for both reactant and active groups. The reaction rate was up to 0.821 × 10^-3 M/m² min at 80 °C in the initial stage without any inductive period for this system. Meanwhile, the selectivity to cumene peroxide is maintained at 100% over 1.5 h of reaction. As the reaction has proceeded for 10 h, the conversion of cumene and the selectivity to cumene peroxide were 38% and 51%, respectively. The result was better than that ever reported in the literature. In addition, the order of catalytic activity for various metal ions is Mn(II)Ce(IV)Co(II)Cu(II). However, the selectivity of cumene peroxide decreased with the increase in conversion owing to the side reaction. Fortunately, increasing the oxygen flow rate was one of the practical methods to inhibit the side reaction and promote the selectivity of cumene peroxide.