Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Coal Liquefaction

09.01.2006


Hydration in the presence of borane or iodine catalysts smoothes the way for the liquefaction of semianthracite coal



The tightening of worldwide oil reserves is causing the price of oil to escalate — and makes coal, which is much more abundantly available, an interesting starting material for liquid fuels and chemical raw materials. Researchers at the Max Planck Institute for Coal Research in Mülheim on the Ruhr have developed a new process that makes it possible to liquefy high-grade bituminous coal (semianthracite coal) for the first time. This type of coal has previously been used exclusively in combustion and gasification processes.

“Methods of coal liquefaction have been available since the beginning of the last century, but the cost has caused us to search for more effective new processes,” explains Matthias W. Haenel. Coal is a complicated, difficult to analyze mixture of organic components. In what is called the Bergius process for direct coal liquefaction, the coal is treated with hydrogen under pressure (>30 MPa) at 450 °C in the presence of a solvent and an iron oxide catalyst. The activity of this catalyst is low, however, because the solid iron oxide cannot enter the macromolecular network structure of the insoluble coal. Semianthracite coal, which only contains a small amount of volatile components, cannot be converted by this process at all. Haenel and his team hoped that a soluble catalyst would serve them better. They thought the family of borane catalysts, boron–hydrogen compounds known to transfer hydrogen atoms to organic molecules, seemed especially promising. Their studies of a German Magerkohle (low-volatile bituminous coal) showed that a mixture of sodium borohydride and iodine, which formed an iodine–borane catalyst in the reaction mixture, is particularly effective. Surprisingly, under the drastic reaction conditions used (25 MPa hydrogen pressure, 350 °C), iodine alone is catalytically active, though boron triiodide is best.


The solubility of the coal in pyridine is drastically increased by this treatment. One reason for this is that carbon–carbon bonds between aromatic and nonaromatic (aliphatic) parts of the molecules are broken and the free “bonding arms” are saturated with hydrogen (hydrated); the network structure of the coal is disrupted. In addition, the double bonds of the aromatic ring systems are partially hydrated so that the aliphatic content rises at the cost of the aromatic. The new process is the first “true” coal hydration in the sense of hydrogen being added to unsaturated structures. Once prepared in this way, high-rank coals could now be liquefied in a subsequent conventional hydrocracking process for the first time.

Author: Matthias W. Haenel, Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr (Germany), http://www.mpi-muelheim.mpg.de/kofo/institut/arbeitsbereiche/haenel/haenel_d.html

Title: The First Liquefaction of High-Grade Bituminous Coals by Preceding Hydrogenation with Homogeneous Borane or Iodine Catalysts

Angewandte Chemie International Edition, doi: 10.1002/anie.200502614

| Angewandte Chemie
Further information:
http://www.mpi-muelheim.mpg.de/kofo/institut/arbeitsbereiche/haenel/haenel_d.html
http://www.angewandte.de

More articles from Life Sciences:

nachricht A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Biocompatible 3-D tracking system has potential to improve robot-assisted surgery

17.02.2017 | Medical Engineering

Real-time MRI analysis powered by supercomputers

17.02.2017 | Medical Engineering

Antibiotic effective against drug-resistant bacteria in pediatric skin infections

17.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>