BioFacts

The most important at least partially bio-based surfactants in washing powder and detergents, in dishwashing and car cleaning are alkyl polyglycosides (APGs) or non-ionic surfactants. APGs are a chemical compound of sugars and alcohols. The fatty alcohols used are based either on fossil raw materials or on short-chain fatty acids, which are usually obtained from palm kernel or coconut oil. APGs are relatively more expensive due to the high demand for these oils and their costly production – in the case of petroleum-based alcohols. What’s more, the use of the initial products is unsustainable. In the BioFacts project, Fraunhofer UMISCHT uses a newly developed process to produce the alcohols required for APGs from ethanol at a competitive price. Ethanol is available worldwide in large quantities and is currently already produced from sustainable raw materials such as straw and wood that do not compete with food.

Not only is it costly to produce the fatty alcohols currently used but, depending on the initial product, they are also in direct food competition. This can be avoided with the aid of the new process that catalytically couples ethanol. The result is low-cost fatty alcohols that enable completely bio-based APGs to be produced.

In a first step, non-food ethanol is coupled in continuous operation to form a mixture of longer, linear, and branched alcohols. The APGs are produced during the next step. The mixture is reacted with a sugar. Depending on the extent of branching in the alcohols used, the end products tend to foam to varying degrees, which has an influence on the area of application. Highly foaming products, for example, are mainly used in the household-related sector. These include car washes, tank cleaning, and dishwashing detergents. Products that foam less are primarily found in the industrial cleaning and cosmetics sectors.

Proximity to the end consumer plays a particular role, especially in household-related applications. The direct perceptibility of the new product among customers strengthens marketing and can accelerate the establishment of bio-based products.

The use of non-food ethanol to produce AGPs offers a recycling alternative to already established bio-based processes – for example, in the fuel market, for which ethanol is mainly produced today. Due to higher margins and sustainability, material use is preferable. New recycling methods must also be opened up for the German ethanol market because of the falling customs barriers for ethanol.