Weissenstein process

Lowenstein-Riedel An electrolytic process for making hydrogen peroxide by the electrolysis of a solution of sulfuric acid and ammonium sulfate. Ammonium peroxodisulfate, (NH4)2S208, is an intermediate. This, and the Weissenstein process were made obsolete with the invention of the AO process. 

Another preparative method involves electrolytic conversion of aqueous sulfuric acid to peroxydisulfate followed by hydrolysis to H2O2 (Weissenstein process). The reaction steps are as follows ... 

The first hydrogen peroxide plant to go on-stream based on the electrochemical process was in 1908 at the Osterreichische Chemische Werke in Weissenstein. The Weissenstein process was adapted in 1910 to afford the Miincher process developed by Pietzsch and Adolph at the Elecktrochemische Werke, Munich. In 1924, Reidel and Lowenstein used ammonium sulfate under the conditions of electrolysis instead of sulfuric acid, and the resulting ammonium peroxodisulfate (Reidel-Lowenstein process) or potassium peroxo-disulfate (Pietzsch-Adolph process) was hydrolysed to hydrogen peroxide. As a result of this process, production of hydrogen peroxide as 100% m/m rose to approximately 35 000 metric tonnes per annum.5... 

Figure 25 shows a single cell of a bipolar electrolyzer, consisting of 26 such elements, for the production of (NH/O2S2O8 from (NH4)2SC>4 as an example [60, 61]. Other cells used today origine from the former Weissenstein process (see next page). Their basic layout is described in [57]. 

First operated in 1908 at the Osterreichische Chemische Werke, Weissenstein, Austria, and then by Degussa, Germany. This process, as well as the other electrolytic processes, was made obsolete by the invention of the AO process. 

Alternative, albeit minor processes for the production of hydrogen peroxide include other autoxidation processes, notably the 2-Propanol Process (Shell Process) and electrochemical processes, including the Degussa-Weissenstein, Munchner, and Riedel-Loewenstein Processes. See, (a) Harris, C.R. (1945) Production of hydrogen peroxide by partial oxidation of alcohols. US Patent 2,479,1 llA, filed Jun. 29, 1945 and issued Aug. 16, 1949 (E. I. du Pont de Nemours) (b) Rust, F.F. (1955) Manufacture of hydrogen peroxide. US Patent 2,871,104A, filed Jan. 31, 1955 and issued Jan. 27, 1959 (Shell Dev) (c)N. 

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