Safety, purity, and cost comparison: membrane reformer-based hydrogen generators, versus hydrogen cylenders and electrolysis.

A main safety advantage of the membrane reformer-based hydrogen generators comes about because the hydrogen output is limited. The output with the smaller generators is small enough that, if your lab is reasonably ventilated, you can never get enough hydrogen in an area to form an explosive mixture. With a cylinder, by contrast, there is always the worry that someone will mis-tighten a fitting or open the wrong valve, and will dump the entire cylinder of gas into one corner of the lab where it will reach explosive composition. The explosive limits of hydrogen in air occur where the hydrogen content is above 4.5% and below 75% for air at room temperatures.

The cost and convenience advantage of membrane reactor hydrogen appears mostly for larger delivery volumes. Hydrogen in cylinders cost, in Detroit where we are, about $60 for 135 scf of 99.98% pure hydrogen. If you use this much every hour, for example, you will find that our largest generator, the Me150, will save you about $1.5 MM over three years. You also won't have to switch out cylinders as often, and you will have a safety and zoning advantage of not having large quantities of explosive hydrogen on site. The cost advantage over electrolyzer hydrogen is smaller, but real. Click here for a price/flux comparison.

As a final advantage, hydrogen from these membrane reactors tends to be purer than hydrogen from cylinders or from electrolyzers since we filter it through a metal membrane. Depending on the fittings we use, the delivered hydrogen can be 99.9999% pure or purer. By contrast, unfiltered cylinder hydrogen is generally 99.98 to 99.999% pure. For customers who would prefer to use cylinder hydrogen, we sell membrane purifiers used to increase the purity of cylinder gas to 99.99999% purity.