Using gas mixtures of CO, CO and H as microbial substrates: the do's and don'ts of successful technology transfer from laboratory to production scale.

The reduction of CO emissions is a global effort which is not only supported by the society and politicians but also by the industry. Chemical producers worldwide follow the strategic goal to reduce CO emissions by replacing existing fossil-based production routes with sustainable alternatives. The smart use of CO and CO /H mixtures even allows to produce important chemical building blocks consuming the said gases as substrates in carboxydotrophic fermentations with acetogenic bacteria. However, existing industrial infrastructure and market demands impose constraints on microbes, bioprocesses and products that require careful consideration to ensure technical and economic success. The mini review provides scientific and industrial facets finally to enable the successful implementation of gas fermentation technologies in the industrial scale.