A test campaign was carried out to generate renewable hydrogen based on wood gas derived from the commercial biomass steam gasification plant in Oberwart, Austria. The implemented process consisted of four operation units: (I) catalyzed water−gas shift (WGS) reaction, (II) gas drying and cleaning in a wet scrubber, (III) hydrogen purification by pressure swing adsorption, and (IV) use of the generated biohydrogen (BioH 2 ) in a proton exchange membrane (PEM) fuel cell. For almost 250 h, a reliable and continuous operation was achieved. A total of 560 (L n dry basis (db) )/h of wood gas were extracted to produce 280 (L n db )/h of BioH 2 with a purity of 99.97 vol % db . The catalyzed WGS reaction enabled a hydrogen recovery of 128% (nḂ ioH 2 )/(nḢ 2 ,wood gas ) over the whole process chain. An extensive chemical analysis of the main gas components and trace components (sulfur, C x H y , and ammonia) was carried out. No PEM fuel cell poisons were measured in the generated BioH 2 . The only detectable impurities in the product were 0.02 vol % db of O 2 and 0.01 vol % db of N 2 .

The oxidation of several phenothiazine drugs (phenothiazine, promethazine hydrochloride, promazine hydrochloride, trimeprazine hydrochloride and ethopropazine hydrochloride) has been carried out in aqueous acidic media by electrochemical, chemical and enzymatic methods. The chemical oxidation was performed in acetic acid with hydrogen peroxide or in formate buffers using persulfate. The enzymatic oxidation was performed in acetate or ammonium formate buffer by the enzyme horseradish peroxidase in the presence of H 2 O 2 . Molecules with, in the lateral chain, two carbon atoms (2C) separating the ring nitrogen and the terminal nitrogen, showed two parallel oxidation pathways, that is (i) formation of the corresponding sulfoxide and (ii) cleavage of the lateral chain with liberation of phenothiazine (PHZ) oxidized products (PHZ sulfoxide and PHZ quinone imine). Molecules with three carbon atoms (3C) separating the two nitrogens were oxidized to the corresponding sulfoxide. The chemical oxidation of all the studied molecules by hydrogen peroxide resulted in the corresponding sulfoxide with no break of the lateral chain. Oxidation by persulfate yielded, for the 3C derivatives, only the corresponding sulfoxide, but it produced cleavage of the lateral chain for the 2C derivatives. The origin of the distinct oxidation pattern between 2C and 3C molecules might be related to steric effects due to the lateral chain. The data are of interest in drug metabolism studies, especially for the early search. In the case of 2C phenothiazines, the results predict the possibility of an in vivo cleavage of the lateral chain with liberation of phenothiazine oxidized products which are known to produce several adverse side effects.

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