Alternative Use for Biogas Plants – Producing Waxes from Biogas for the Cosmetics Industry

Synthesis of high-quality biowaxes from biogas at laboratory scale
Professor of Reaction Engineering at the Institute of Energy Process Engineering and Chemical Engineering at TU Bergakademie Freiberg develops new catalysts for Fischer-Tropsch synthesis.

Initiated in April 2017, a collaborative project between TU Bergakademie Freiberg, the Fraunhofer Institute for Ceramic Technologies and Systems (IKTS)and four companies from Saxony is aimed at demonstrating the production of biowaxes from a biogas plant, while evaluating the economic viability of the system.

Until now, biogas was simply burned to produce electricity, or transformed into biomethane and fed into the gas network. As the feed-in tariffs are heavily dependent on governmental funding policy frameworks, the additional manufacture of biowaxes from biogas could provide subsidy-independent income perspectives for the 270 biogas plants currently operating in Saxony.

Currently, over 8,000 biogas plants are in operation in Germany. The higher costs involved in producing electricity from biogas (in comparison to electricity produced from fossil fuels) are offset by feed-in tariffs defined under Germany’s Renewable Energy Act (EEG). Over the last 20 years, this regulatory framework has led to significant growth in the number of biogas plants in Germany. However, their economic viability remains closely linked to the feed-in tariff. A reduction in the tariff – as proposed in a recent amendment to the EEG – could spell economic disaster for many existing biogas plants.

Economic independence through alternative biogas utilization

Concepts that could lead to subsidy-independent viability are, therefore, of considerable interest to both biogas plant manufacturers and operators. “One possible concept is the alternative use of biogas for the manufacture of high-quality chemical products,” says Dr. Erik Reichelt, a scientist at Fraunhofer IKTS. “The transformation of biogas to biowaxes represents a promising future option for existing plants.”

Biogas consists of methane and carbon dioxide, with the CO² long regarded as an unusable byproduct of the process. This could change, however, if the carbon dioxide in biogas can be used in the synthesis of waxes. The first step is the production of a so-called “syngas”, or synthesis gas. This is realized in a biogas reformer at very high temperatures and with catalytic support. Subsequently, the Fischer-Tropsch process is used to synthesize high-value, high-quality waxes that could even be labeled as organic. “The development of appropriate catalysts– meaning that they are efficient and exhibit sufficient long-term durability – is a particularly great challenge, and we are taking on that challenge as part of this task,” says Prof. Dr. Sven Kureti from TU Bergakademie Freiberg.

Use of biowaxes in cosmetic products and as lubricants

Because of their high degree of purity, these waxes are particularly suitable for the cosmetic industry. Most commercially available creams are based on petroleum derivatives, which in some cases can trigger allergies or intolerances. In contrast, biowaxes are much more compatible with the human body, as they are free of impurities. Therefore, biowaxes could find lucrative fields of application – and especially in the natural cosmetics industry.

In addition, biowaxes can be used as lubricants. The purity of the waxes guarantees constant product composition and, therefore, reliable characteristics – qualities that are not fully achievable with mineral oil-based lubricants. Product quality is an important criterion in consumers’ purchasing decisions, and a “Biosiegel” (organic label) can provide a significant competitive advantage in this industry.

Field testing the biowax process and analysis of its economic viability

Within the framework of the three-year project – supported by the Development Bank of Saxony (SAB) and with EDRF funding – this promising process technology will now be examined in detail. In particular, the project will focus on the setting-up and operation of a pilot plant for the production of wax at a biogas plant. The viability of the concept will then be evaluated on the basis of the process data obtained.

Flasche und Schale mit "Diesel" und "Wachs"

This collaborative project will bring together a range of companies, universities and research institutes from across Saxony. As a company specializing in gas-specific technologies, DBI Gas- und Umwelttechnik GmbH will be concerned with the development of the gas reformer. The reformer may be regarded as the heart of the processing plant, together with the Fischer-Tropsch reactor developed by the Fraunhofer IKTS – for which the Chair of Reaction Engineering at the Institute of Energy Process Engineering and Chemical Engineering, TU Bergakademie Freiberg is developing new catalysts. The facility will be planned and built by Advanced Machinery & Technology Chemnitz GmbH. In order to demonstrate the process, Oekotec Anlagenbau GmbH will incorporate their know-how and operate the plant at one of their existing biogas plants. Sunfire GmbH will undertake the economic evaluation of the concept as a whole.

“With the successful completion of the project, we will be in a position to offer a technology that will provide our customers with a choice, for the first time, between the production of energy and the manufacture of sustainable products,” says Gerhard Wilhelm, Managing Director of Oekotec Anlagenbau GmbH. “This will open up new perspectives for the biogas industry. For our company, this innovation signifies not only the expansion of our product portfolio with a new unique selling point, but the considerable strengthening of the company.”

(Amended press release from Fraunhofer IKTS, 23. May 2017)

Prof. Dr. Sven Kureti, Tel. +49 3731 39-4551,