December 08 2008 / by Garry Golden
Category: Energy Year: 2020 Rating: 1
Have you ever held natural gas in your hand?
“It ('dry water') looks like a powder, but if you wipe it on your skin, it smears and feels cold” says Andrew Cooper University of Liverpool, UK
Chemists at the University of Liverpool have developed a reliable way of converting methane gas into a powder form in order to make it more transportable.
The researchers use a white powder material made of a mixture of silica and water to soak up large quantities of methane molecules.
Liverpool researchers believe that instead of shipping methane as a 'gas' or 'liquid' (LNG) we can transport it as a powder. It is also possible to use solid natural gas storage being used for electric vehicles that use fuel cells that convert natural gas (on board) into electricity.
Easier method to make store methane in a powder
It does not make sense to store all natural gas as a solid, but the market opportunities are significant. The challenge of methane gas hydrate has been that it is formed at a very slow rate when methane reacts with water under pressure. "To counteract these difficulties we used a method to break water up into tiny droplets to increase the surface area in contact with the gas. We did this by mixing water with a special form of silica – a similar material to sand – which stops the water droplets from coalescing.
This 'dry water' powder soaks up large quantities of methane quite rapidly at around water's normal freezing point."The team also found that 'dry water' could be more economical than other potential products because it is made from cheap raw materials.
Why is this important to the future?
Storing gas as a solid?
First, ask why natural gas - and a review of the basics of energy.
The modern world exists because we capture the energy released when chemical (hydrocarbon) bonds break apart. The more hydrogen molecules involved the better the fuel. If you don't use these hydrocarbons for energy, then they make a great feedstock for materials and 'petroproducts'.
Methane is a hydrogen rich source of energy, but difficult to transport. [Pure H2 is also difficult to transport, and we've written extensively on the notion of storing hydrogen as a solid based on materials with high surface area that can easily bind and release hydrogen molecules.]
Energy industry analysts often describe natural gas as the 'fuel of the 21st century', or if not the 'fuel', it will be a major materials feedstock of the next 50 years.
There are those who believe that the world has tremendous natural gas resources, and those who believe that 'peak' natural gas is likely within 50 years.
But everyone agrees that it is hard to transport!
Methane gas hydrate forms naturally when water is mixed with methane at high pressure and low temperature. Huge deposits of the crystalline substance exist in the deep sea, where they could provide vast fuel reserves.
"This is a very important issue", says E. Dendy Sloan, a specialist in natural hydrates at the Colorado School of Mines in Golden, who was not connected with the research. About 70% of the world's natural-gas stores, says Sloan, are in small, remote reservoirs from which it is not economical to run a pipeline.
Image Credit - Liverpool