Chemistry

Handbag

Leather production: hazardous to health and harmful to the environment

Some steps in leather production are extremely unsavory. In order to be able to process and preserve the hide, it has to be tanned. Classical tanning processes use substances that are harmful to health and pollute soils and waters considerably. In addition to the harmful substances, animal farming is also problematic, because not every animal skin is a waste product.

Fertilizer from bagasse ash

Along with soya and corn, sugar cane is one of the most important crops in Brazil. It is used to produce not only sugar but also biofuels such as ethanol. However, processing produces enormous amounts of bagasse - fibrous remains - which up to now were not used efficiently. Instead, the lignocellulosic residual material is burnt in inefficient incinerators and usually disposed of in landfills or scattered on fields. But ash is more than just burned biomass. It contains nutrients such as phosphorus, which are essential for plant growth.

An on-farm biorefinery

If it were up to Andrea Kruse, every farmer would have his own biorefinery. Waste materials such as grass, straw or wood would be broken down into their components in a mini plant and converted into new products such as platform chemicals. The idea of the Hohenheim chemist is by no means utopian. Such an on-farm plant was inaugurated at the end of October on the site of the experimental station at the University of Hohenheim on Unteren Lindenhof. "We still need about three years before all teething troubles are resolved.

Deruster

Counteracting rust

The brown coating is formed when iron oxidizes. Rust is not only unattractive, it also causes damage because it continues to decompose the metal. Conventional rust solvents contain acids as an effective component, usually phosphoric or hydrochloric acid. These reverse the process and stop the formation of rust. Acids, however, are dangerous to handle and pollute the environment.

Running shoes

Ideal properties

As synthetic materials are much easier to care for than leather and also resistant to moisture, they are increasingly being used as uppers for running shoes. adidas uses a very special material in its new "Futurecraft Biofabric Shoe". The upper of the shoe is made entirely of artificial spider silk. Spider silk is extremely robust. The threads are thinner than a hair, yet more tear-resistant than steel, more elastic than rubber and also ultra-light.

Engine cover

Castor oil protects the engine

Components in the engine compartment of a car must be able to withstand extreme heat loads of over 200 degrees Celsius. Daimler uses biopolyamide engine covers for the Mercedes A-Class. While conventional plastic is produced from crude oil, the cover consists largely of castor oil. The oil is extracted from the seeds of the castor oil plant Ricinus communis, which belongs to the spurge family.

Cleaner

Straw to alcohol

Alcohol has fat and dirt dissolving properties, therefore it is particularly well suited as an additive to cleaners. In cooperation with the chemical company Clariant, the family-owned company Werner & Mertz, known for its ecological and environmentally friendly “Frosch”-products has tested the use of bioethanol based on straw in washing and cleaning agents. 

Trainers

Sustainable remake

The rice husks replace a part of the rubber used for the outsoles, thereby decreasing the quantity of petroleum-based rubber in the shoe. Compared to conventional products, the `Re-Suede´ reduces CO2 emissions by 80%. This is because not just the outsole is made from waste materials. The synthetic Ultrasuede upper material is also comprised of recycled polyester fibres. The remake of Puma’s classic trainer ‘Suede’ was designed as an eco-product based mainly on recycling.

Smart molecular building blocks

Our bodies, windows or plastic bottles – all of them are made up of different molecules. The big difference however: while the molecules in the human body or other living organisms are in constant exchange with their surroundings, artificially produced material is not. This in turn directly affects their ability to break down after being used.

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