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A small type of rotating disk generator (Autodisk) for O2(1(Delta) )--based on the chemical reaction between basic hydrogen peroxide (BHP) and chlorine--has been examined with respect to the variation of several parameters: the type of inert gas (Ar, He, Ne) added to the chlorine, the flowrate of chlorine at a constant ratio nCl(subscript 2)/nHe, the flowrate of helium at a constant chlorine flow rate and the composition of the BHP. In addition the material of the disks (nickel, polycarbonate, plexiglass) and the number of disks was varied in order to estimate the influence of surface effects on the O2(1(Delta) )-yield. The type of buffer gas did not affect the O2(1(Delta) )-yield (up to 55%) with a 7.4/0.6 BHP mixture (i.e. 7.4 M KOH and 0.6 M H2O2 in excess) and flowrates of chlorine and buffergas of 1 mmol/s and 3 mmol/s, respectively. Here, the chlorine utilization of 86%. Long time operation of 25 min has been achieved with BHP concentration of 6.8/0.6 resulting in the same O2(1(Delta) )-yield but in lower chlorine utilizations (78%). Replacement of the heavy nickel disks by lighter plastic disks with lower moment of inertia made the operation of the Autodisk much more flexible. The chlorine utilization was slightly affected by the material of the disks and dropped about 2% (Cl2/He-flowrates: 1/3). The variation of the reacting surface had a nonlinear influence on the utilization of chlorine (1 mmol/s; 6 polycarbonate disks: 69%, 10 disks: 84%, 17 disks: 93%). It is assumed that the smaller separation of the disks increased the amount of BHP in the free space between the disks. This reduced the available reaction surface and the chlorine transit time in the generator.
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