Fats and oils as renewable feedstock for chemistry

Agenda 21, the comprehensive plan of action for a sustainable development in the 21 century which was adopted by more than 180 governments in Rio de Janeiro in 1992, is encouraging the environmentally sound and sustainable use of renewable natural resources, interestingly in chapter 4 “Changing consumption patterns”[1]. It was estimated that about 120 billion tons carbon in biomass, equivalent to .80 billion tons of oil equivalents (toe), are generated globally year by year by photosynthesis [2]. About 5% are presently used by man. The global primary energy supply was in 2004 11.2 billion toe and was estimated to be in 2030 20.6 billion toe [3]. Obviously, there seems to be plenty of biomass available, continually generated by photosynthesis year after year. Moreover, mankind has been degrading, in historical times, some billion hectares of areas originally forested and covered with vegetation. Reforestation of these degraded areas is the greatest challenge on the way to a sustainable development. Neglect of reforestation implies that desertification will further progress, transforming more and more of the areas prone to desertification into new deserts [4]. Thus, there is enough land available for the production of biomass to be used as renewable feedstock. Chemists have much to contribute to meet this challenge [5, 6]. From a chemical point of view, about 75% of biomass is carbohydrates, 20% lignins and only about 5% fats and others. Obviously, the detailed knowledge of the chemistry of these biomolecules will be absolutely necessary on the way to a sustainable usage of biomass as renewable feedstock. At present, the feedstocks of the chemical industry are predominantly depleting fossil feedstocks – oil and natural gas – and only a small percentage are renewables, in Germany about 12%. Thus, the chemical industry will have to change its consumption pattern. The German Chemical Society stated in 2002, on the occasion of the World summit on sustainable development in Johannesburg: “Most products obtainable from renewable raw materials may at present not be able to compete with the products of the petrochemical industry, but this will change as oil becomes scarcer and oil prices rise” [7]. This is currently going on. Some examples of this breathtaking process will be discussed in this paper focused on polyols and middleand long-chain dicarboxylic acids. Moreover, the importance of cultivating new oil plants for chemical usage of the oil will be discussed shortly.