Extending the life of oil reserves
Greener, cheaper more efficient oil extraction made possible at ISIS
A research team led by the University of Bristol has used STFC's ISIS Neutron Source to come up with a new way to treat carbon dioxide (CO2), so that it can be used in efficient and environmentally friendly methods for extracting oil. These new CO2 soluble additives can also be used to reduce the environmental damage caused by every day industrial processes such as food processing and the manufacture of electronics. The results of this work are published in the journal Langmuir.
L to R: Azmi Mohamed, Stephen Cummings and Masanubo Sagisaka (all University of Bristol) with instrument scientist Dr Sarah Rogers (ISIS), with the sample pressure cell for the Sans2d instrument.
The researchers have developed a soap-like additive for CO2 that turns it into a viable solvent for commercial-scale enhanced oil recovery to increase the amount of crude oil that can be extracted from oil fields.
“Carbon dioxide is useful in enhanced oil recovery as it is able to flow through the pores in the rock much more easily than water,” said Professor Julian Eastoe from the University of Bristol. “The additive, a surfactant, will help thicken the carbon dioxide, which is vital for this process, allowing it to flow through the rock more efficiently. There is also a useful side effect of our ability to use CO2 in this way, as in the future the process will take carbon dioxide generated by industrial activity from the atmosphere and lock it deep underground. Getting longer life out of existing oil reserves will also give more time for research into replacements into non-carbon energy sources such as solar or hydrogen.”
Minister for Science and Universities David Willetts said: “This shows what science can do for the environment. It’s why the Government has protected the science budget. In particular it shows how financing core science facilities can lead to many different projects with valuable applications.
Instrument scientist Dr Sarah Rogers(ISIS), releasing CO2 into a pressure cell at the sample position on the Sans2d instrument.
Liquid CO2 is increasingly being used industrially to replace common petrochemical solvents because it requires less processing and it can be easily recycled. The difficulty has been that in order to operate effectively as a solvent, carbon dioxide needs additives, many of which are in themselves, damaging to the environment. This new development by an international team including scientists from Bristol University led by Professor Julian Eastoe, from the University of Pittsburgh led by Professor Bob Enick and ISIS scientists Dr Sarah Rogers and Dr Richard Heenan provides a solution. The project has been funded by the UK Engineering and Physical Sciences Research Council (EPSRC) and the US Department of Energy to explore using high pressure CO2 to extract residual oil retained in the pores of rock.
“The quest to find a chemical capable of modifying the properties of CO2 to make it suitable for widespread use as a solvent in enhanced oil recovery has been long,” said Professor Bob Enick. “Previous advances have involved surfactants containing fluorine, which although highly soluble in CO2, are very environmentally damaging. The new additive, surfactant TC14, contains no fluorine at all and is a harmless hydrocarbon.”
CO2 offers an efficient, cheap, non-toxic, non-flammable and environmentally responsible alternative to conventional petrochemical solvents. Even water as a solvent for example, comes with its own set of problems; after being used to flush out oil from rocks it then requires cleaning before it can be used again, whereas liquid CO2 can be re-used immediately.
The paper published in the Langmuir is the first to come from Sans2d, one of seven new neutron instruments built at the ISIS second target station, a £145 million expansion to the facility completed last year. It is also one of the first to be published using data collected at the new target station.
The new additive, surfactant TC14 enables small pockets to form in the liquid CO2 called reverse micelles causing the liquid to thicken. Neutron scattering at ISIS allowed the structure of the reverse micelles to be studied in the CO2 as they formed under high pressure. The neutron instruments giving this molecular level viewpoint are often described as ‘super-microscopes’.
“Beams of neutrons are able to penetrate deep inside samples giving unique information about the location and arrangement of the micelles at a molecular level,” said ISIS scientist Dr Sarah Rogers.
“By altering the pressure in a specially constructed experimental cell, dissolved material can easily be separated and removed leaving the carbon dioxide for the next use. It would be difficult to look at this system using any other technique as the CO2 needs to be kept under high pressure. Only under the scrutiny of neutron beams can you fully reveal its actions and properties.”
“Experiments on Sans2d are particularly fast and accurate in comparison to some older neutron scattering instruments. This development of neutron instrument technology is part of what makes ISIS a world leading science facility,” said Professor Eastoe.
Notes to editors
The research is published in the journal Langmuir:
“Universal Surfactant for Water, Oils, and CO2”
Azmi Mohamed, Kieran Trickett, Swee Yee Chin, Stephen Cummings, Masanobu Sagisaka, Laura Hudson, Sandrine Nave, Robert Dyer, Sarah E. Rogers, Richard K. Heenan, and Julian Eastoe
Vol. 26, No. 17, 13861–13866, DOI: 10.1021/la102303q
The project has been funded by the UK Engineering and Physical Sciences Research Council (EPSRC) (link opens in a new window) and the US Department of Energy (link opens in a new window).
Dr Masanobu’s contribution was made possible by an award from the Japan Society for Promotion (JSPS) of Science. One of the JSPS's missions is to promote international collaboration in science by providing overseas fellowship opportunities for promising young Japanese researchers who will lead Japan's next scientific generation. The JSPS award "Excellent Young Researcher Overseas Visit Program" granted to Dr. Masanobu Sagisaka enabled him to contribute to this cutting-edge project at the University of Bristol, and to collaborate with other UK and US partners.
More images of the scientists working on the Sans2d instrument are available. Please contact the Press Office for more details
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About the ISIS Neutron Source
ISIS (link opens in a new window) is a world-leading centre for research in physical and life sciences operated by the STFC at the Rutherford Appleton Laboratory, Didcot, Oxfordshire, UK.
ISIS produces beams of neutrons and muons that allow scientists to study materials at the atomic level using a suite of instruments, often described as ‘super-microscopes’. ISIS supports an international community of over 2000 scientists who use neutrons and muons for research in physics, chemistry, materials science, geology, engineering and biology. It is the most productive research centre of its type in the world.
The £145 million ISIS Second Target Station Project was completed in August 2009. The experimental programme at the new target station complements the facilities already operating at ISIS and enables the science programme to expand into the key research areas of soft matter, advanced materials and bio-science.
About Neutron Scattering
Neutron scattering is a vital research and analysis technique in exploring the structure and dynamics of materials and molecules. It provides unique and complementary information to that available from synchrotron light sources.
At ISIS, a synchrotron accelerator speeds a proton beam to 84 percent the speed of light before it is fired at a small tungsten target to make neutrons. The neutrons released from the target are then channeled along evacuated beampipes into the material being examined.
Neutrons have no electric charge and penetrate deep inside materials. By looking at how neutrons scatter off the atoms inside materials, they reveal the atomic structure of the material under study. This enables researchers to correlate the structure of materials with their properties and understand how they behave in different circumstances.
The University of Bristol
The University of Bristol (link opens in a new window) is consistently ranked among the leaders in UK higher education. According to The Times Higher Education World University Rankings 2009, it is among the top 35 universities in the world.
Research-intensive and with an international reputation for quality and innovation, the University has 17,000 students from over 100 countries, together with more than 5,500 staff. In terms of the number of applications per undergraduate place, Bristol is arguably the most popular university in the country.
The University of Pittsburgh
More information can be found on the University of Pittsburgh (link opens in a new window) website.
The Engineering and Physical Sciences Research Council (link opens in a new window) (EPSRC) is the main UK government agency for funding research and training in engineering and the physical sciences, investing more than £850 million a year in a broad range of subjects – from mathematics to materials science, and from information technology to structural engineering.