Hoechst Aktiengesellschaft

Harald Haberlein, Deceased

Frank Ebmeyer

Manfred Gscheidmeier

By Hans Haberlein, Heir

Jorg Thomas Haberlein, Heir

By Jorg Haberlein, Heir

Mark Christian Haberlein, Heir

Holger Mohn

Hans Harald Haberlein, Heir

By Mark Haberlein, Heir

Process for the preparation of camphene by the rearrangement of .alpha.-pinene A process for the preparation of camphene by the rearrangement of .alpha.-pinene in the presence of a titanium oxide hydrate catalyst under the action of heat, wherein .alpha.-pinene is refluxed until the content of .alpha.-pinene in the reaction mixture is still at least 3% by weight, and the rearrangement is then brought to completion in a secondary reaction at a temperature below 160.degree. C. By carrying out the process in this way--refluxing to a relatively high residual content of .alpha.-pinene and performing a secondary reaction at a lower temperature--the formation of polymeric by-products is reduced. This process moreover increases the yield of camphene in that recycled tricyclene, concentrated in the distillation of the crude product, is partially rearranged to camphene or the formation of more tricyclene is reduced.

Process for the preparation of camphene by the rearrangement of a-pinene

The present invention relates to a process for preparing a particularly pure glycolic acid by saponification with chloroacetic acid with an excess of alkali metal hydroxide, with the resulting alkali metal chloride being filtered off, and the 20 to 70% strength by weight glycolic acid solution being subsequently subjected to an electrodialysis at 20.degree. to 40.degree. C. and a cell voltage of 0.5 to 2.5 V per cell pair. The process of the invention permits optimum removal of sodium chloride and chloroacetic acid as necessary for preparing a particularly pure glycolic acid. Other organic acids, nitrogen compounds, aldehydes and salts are not produced in this process and thus do not affect the product quality.

Process for preparing a particularly pure glycolic acid

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Neusass, Germany

Harald Haberlein, Deceased