My watch list  

Biomass as a source of raw materials

New process for obtaining alkanes from bio-oil


For the protection of the environment, and because of the limited amount of fossil fuels available, renewable resources, such as specially cultivated plants, wood scraps, and other plant waste, are becoming the focus of considerable attention. Processes such as pyrolysis or liquefaction allow the conversion of biomass into bio-oil, a highly promising renewable source of energy. A team of German and Chinese scientists led by Johannes A. Lercher at the Technical University of Munich has now developed a new catalytic process to convert components of bio-oil directly into alkanes and methanol. As reported in the journal Angewandte Chemie, the process is based on a "one-pot" reaction catalyzed by a precious metal on a carbon support combined with an inorganic acid.

Bio-oil is an aqueous, acidic, highly oxidized mixture. However, its high oxygen content and instability turn out to have a negative impact: bio-oil cannot be used directly as a liquid fuel. It would, however, be highly interesting as a source of basic raw materials if it were possible to convert it to alkanes. Alkanes, which are also commonly called paraffins, are saturated hydrocarbons; they are among the most important raw materials for chemical industry, and in particular as starting materials for the production of plastics. Furthermore, they are among the primary fuels in the world's economy.

Bio-oil contains a phenolic fraction consisting of compounds with the main framework being an aromatic ring made of six carbon atoms with some hydroxy (-OH) groups attached. With the new process, the phenolic components of bio-oil can be converted with high selectivity to cycloalkanes (ring-shaped alkanes) and methanol. The researchers were able to demonstrate this with various model substances. As catalyst, they used palladium metal on a carbon support, with phosphoric acid as the proton source for the reaction.

The reaction is a "one-pot" reaction, meaning a one-step reaction whose partial reactions (hydrogenation, hydrolysis, and dehydration) occur in the same reactor, with no intermediate work-up. The secret is in the catalyst, which works on all of these different reactions. The end result is a mixture of various alkanes that separates into a second phase, making it easy to separate from the aqueous bio-oil phase. The new process is a practical approach for the direct use of bio-oil for the production of alkanes.

Original publication: Johannes A. Lercher et al.; "Highly Selective Catalytic Conversion of Phenolic Bio-Oil to Alkanes"; Angewandte Chemie International Edition 2009, 48, No. 22, 4047-4050

More about Wiley
More about Angewandte Chemie
  • News

    Doped Photovoltaics

    Organic solar cells are made of cheap and abundant materials, but their efficiency and stability still lag behind those of silicon-based solar cells. A Chinese-German team of scientists has found a way to enhance the electric conductivity of organic solar cells, which increases their perfor ... more

    Analysis and Detoxification in One Step

    Many industrial and agriculture processes use chemicals that can be harmful for workers and the ecosystems where they accumulate. Researchers from Thailand have now developed a bioinspired method to detect and detoxify these chemicals in only one step. As they report in the journal Angewand ... more

    Striped Glow Sticks

    It may be possible to reach new levels of miniaturization, speed, and data processing with optical quantum computers, which use light to carry information. For this, we need materials that can absorb and transmit photons. In the journal Angewandte Chemie, Chinese scientists have introduced ... more

More about TU München
  • News

    Light in the nanoworld

    An international team headed up by Alexander Holleitner and Jonathan Finley, physicists at the Technical University of Munich (TUM), has succeeded in placing light sources in atomically thin material layers with an accuracy of just a few nanometers. The new method allows for a multitude of ... more

    Artificial neural network resolves puzzles from condensed matter physics

    For some phenomena in quantum many-body physics several competing theories exist. But which of them describes a quantum phenomenon best? A team of researchers from the Technical University of Munich (TUM) and Harvard University in the United States has now successfully deployed artificial n ... more

    Activity of fuel cell catalysts doubled

    An interdisciplinary research team at the Technical University of Munich (TUM) has built platinum nanoparticles for catalysis in fuel cells: The new size-optimized catalysts are twice as good as the best process commercially available today. Fuel cells may well replace batteries as the powe ... more

  • Videos

    Scientists pair up two stars from the world of chemistry

    Many scientists consider graphene to be a wonder material. Now, a team of researchers at the Technical University of Munich (TUM) has succeeded in linking graphene with another important chemical group, the porphyrins. These new hybrid structures could also be used in the field of molecular ... more

Your browser is not current. Microsoft Internet Explorer 6.0 does not support some functions on Chemie.DE