Effects of lonenes on structure and catalytic activity of cobaltphthalocyanine, part 4. Reaction mechanism and immobilization of the catalyst on latex particles

Abstract

The catalytic oxidation of 2‐mercaptoethanol was investigated kinetically for the system cobalt(II)phthalocyanine‐tetra (sodium sulphonate) in the presence of poly(quaternary ammonium salts) at pH = 8.85. From a comparison with other kinetic data a reaction mechanism could be proposed in which the specific effects of the polyelectrolyte become manifest. The effect of ionic strength on the catalytic activity was also studied. The soluble catalytic system was immobilized on latex particles by using a polymeric soap containing quaternary ammonium groups. The latex particles with the ammonium groups at the surface were used to bond the cobalt catalyst by ionogenic interaction. Using this latex supported polymeric catalyst the activity of its homogeneous counterpart could be maintained while at the same time immobilization was accomplished.

Synthesis and Cocatalytic Properties of Polystyrene-Ionene-Stabilized Lattices

“…These results point to simple Michaelis-Menten kinetics according to eq 1 (zeroth reaction order in O2). 29 The minimum turnover frequency for thiol conversion, k', and the apparent Michaelis constant, K'm, calculated by plotting HR vs 1/[ME], a so-called Lineweaver-Burk plot, are (1.2 ± 0.2) x 103 mol ME-(mol of CoPc-(NaSOsk's)™1 and (2.4 ± 0.8) x 10-3 mol of ME-dm"3, respectively. Therefore, we can conclude that the polystyrene-ionene-stabilized latices exhibit Michaelis-Menten kinetics in the mercaptoethanol autoxidation.…”

Catalytic activity of cationic latices prepared according to the shot-growth method

“…The coupling can be described by a Table 3 respectively. Consideration to the occurrence of maxima in these curves is given elsewhere [19,20]. The dependence of reaction rate on thioi concentration at optimum pH and [N +] conditions is depicted in Fig.…”

Effects of complexation of oppositely charged water-soluble cobaltphthalocyanines on the catalytic mercaptoethanol autoxidation

“…Resuming, an adaptation of the reaction mechanism for a CoPc (NaSO,),/ 2,4-ionene system, based on the reductive cycle of Zwart [ 391 and further developed by Van Herk et al [40], is presented in Scheme 1. The catalyst is predominantly present in its dimeric form and leads to a faster ligation of thiolate anions, the subsequent reduction of Co (II) to Co (I), and the simultaneous oxidation of the thiolate anion to a thiol radical.…”