3555.     ---------------.  [VELDE, H.]  [Relation of Octane Number and Peroxide Content of Synthetic (Fischer-Tropsch) Gasoline.]  Oel. u. Kohle, vol. 40, 1944, pp. 10-15; Petrol. Refiner, vol. 25, No. 6, 1946, pp. 137-140; Chem. Abs., vol. 38, 1944, p. 5067.

        Storage tests in brown and transparent bottles with and without exposure to light showed a considerable accelerating effect of light on the peroxide formation, peroxides determined by the method of Yule and Wilson, in primary synthetic gasoline (I), vapor-phase cracked synthetic gasoline (II), and a 1:1 blend of (I) and (II), (III).  All the gasolines were obtained by the Fischer-Tropsch synthesis, (abs. 1018 and 1021) or by processing material primarily made by this process.  The octane numbers of samples containing an appreciable amount of peroxides decreased noticeably; the research octane number of (I) dropped from 58.0 to 37.0 when the peroxide content had reached 325 mg. O₂ per l., the octane no. of (II) fell from 68.1 to 45.0 at a peroxide content of 350 mg. O₂ per l., and (III) decreased from 65.0 to 38.5 at a peroxide number of 305 mg. O₂ per l.  The same gasolines with and without the addition of alcohol, cresol, PbEt₄, or a mixture of all these additives were stored in Fe drums, and it was found that cresol inhibited the peroxide formation almost completely during a storage period of 2 yr.  A definite inhibitor effect was found for alcohol with (I) and (III), PbEt₄ acted as inhibitor for gasolines stored in galvanized Fe drums but was without effect in bare Fe drums.  The relation of octane no. and peroxide no. for the types of gasolines tested is shown in a diagram.  Removal of peroxides by acidic FeSO₄ solution did not completely restore the original octane no.