Given their specific solvent properties, butanol and its derivatives are important ingredients of many paints and varnishes. While the use of solvent has, in general, declined due to a shift towards water-borne paints and varnishes, products based on butanol can also be used as coupling agent in water-borne formulations. Global demand for butanol rose by, on average, 2.7% p.a. between 2005 and 2013.
Various Solvents are Dominating ApplicationButanol is a higher alcohol that is mainly produced through oxo-synthesis of propylene. Almost 12% of total global butanol output are directly used as solvent. The largest share, amounting to almost 1.5 million tonnes in 2013, however, is consumed in manufacturing acrylate, which is used in water-borne paints but also detergents, adhesives, and textiles. The second most important application is the production of acetate, which is used as solvent in automotive coatings or as ingredient in a range of cosmetics and pharmaceutical drugs. Glycol ethers based on butanol are highly suitable for the use as solvent in water-borne varnishes, given their miscibility with water. Also, phthalates manufactured from butanol are playing an important role as plasticizer in the processing of PVC.
Growth Market BiobutanolBesides the commercial use of butanol in chemical applications, this alcohol is also deemed to offer significant potential for the biofuel industry. Already existing and progressing technologies to produce biobutanol by the fermentation of biomass are increasingly becoming the center of attention. Butanol offers a range of advantages when compared to conventional biofuel made from ethanol: Butanol has a higher energy content and is easily miscible with diesel and gasoline. In addition, it can be combusted in conventional Otto-cycle engines without modifying the engine. Bioethanol, however, already is an established biofuel in Europe and North America, and a changeover of production facilities to manufacture biobutanol would be expensive. Another possibility is converting the bioethanol that is being produced into butanol. Adequate technologies, however, are still in the initial stages of development.