Ruhrchemie

For a short time at the beginning of the 20th century, one of the first German airports seemed to be built in the Holtener Bruch, which had been largely drained by the canalization of the Emscher river.

However, it remained with air shows and training flights; the course and outcome of the First World War prevented the airport project from being realized.

In 1938, Otto Roelen developed the oxo synthesis of aldehydes, which are used to produce polyols, carboxylic acids, esters and solvents, among other things.

[1] After 1945, the Allies banned the production of synthetic fuels and dismantled the corresponding plants, which had been badly damaged in the war.

[4] From 2007 to 2020 it was part of Oxea GmbH, which was formed in March 2007 from the merger of European Oxo and selected business units of Celanese Chemicals.