Anti Depression Guide

Many energy experts expect hydrogen to replace fossil fuels in future. But one problem standing in the way of a hydrogen economy is that the polymer exchange membranes used to generate electricity from the conversion of hydrogen and oxygen to water are easily contaminated by gases such as carbon monoxide and methane.

This contamination reduces the membranes' lifetime to such an extent that they cannot compete economically with fossil fuels.

So Timothy Golden of Air Products and Chemicals, a supplier of gases based in Pennsylvania, US, has come up with a way to remove contaminants from hydrogen by pumping the gas through an adsorbent material known as CaLSX – calcium low silica x-zeolite – at pressures of up to 1000 atmospheres.

This removes poisonous gases such as carbon monoxide and other gases like water vapour, oxygen, and nitrogen to leave pure hydrogen, which could significantly increase the lifetime of polymer exchange membranes. The team says that could provide a much needed kick-start to the hydrogen economy.

Read the full hydrogen purifier patent application.

Justin Mullins.

Methanol fuel cells are increasingly touted as potential replacements for conventional batteries in everything from cellphones to laptops. They work by allowing protons from the methanol to flow across a membrane to generate current.

But the membranes they employ have a significant disadvantage – in addition to protons, they allow methanol to cross over as well. This dramatically reduces the efficiency of the fuel cell, not least because the methanol that passes through is wasted.

NowFred Wudl, an organic chemist at the University of California, Los Angeles, US, and colleagues say it is possible to block the passage of methanol through the membrane by plugging gaps within its structure using buckyballs – nanosopic spheres of carbon.

The buckyballs – also called fullerenes – would have chemical groups attached to them that shuttle the protons across the membrane while blocking the progress of methanol molecules.

Membranes made this way would have the potential to dramatically improve the efficiency of Methanol fuel cells, Wudl says.

Read the full buckyball membrane patent application.

Justin Mullins