The Linde Process for Preparing Hydrogen from Water-gas.

Progress, Volume VI, Issue 9, 1 July 1911, Page 718

The Linde Process for Preparing Hydrogen from Water-gas.

(Translated for Progress.)

For some time past hydrogen, of the purity and lifting power requisite for aviation purposes, has been manufactured from water-gas, which contains about 50 per cent, of hydrogen. The favourite method hitherto has been to pass watergas and steam over lime heated to 500 deg., thereby eliminating the impurities of the water-gas, and producing pure hydrogen The new process of Linde has proved both cheaper and more effectual. It is an application of a method originally devised and still used for extracting pure oxygen and nitrogen from air. It consists of a coil of two concentric tubes, the outer of which opens into a small bulb, from which the liquified gas is ultimately drawn off. The inner tube ends in a fine jet. The purified gas is compressed and cooled, and then led through the inner tube at a pressure of about 30001bs. to the square inch. On issuing at the jet it expands and consequently cools, and passes on up the outer tube. In doing so it lowers the tem-

perature of the gas passing down the inner tube, which in its turn expands and cools in the bulb, and passes into the outer tube. The continuance of this process results in the ultimate liquefaction of carbonic oxide at a temperature of 200 deg. C. below zero. The hydrogen in a practically pure gaseous state passes on through the outer tube. This hydrogen can be still further purified by very simple means, until one obtains a gas containing 99.5 p.c. hydrogen, which fully satisfies the demands of aviation. At the same time, a fairly pure carbonoxide is procured, with which the gasmotor used in compressing the water-gas can be driven. The maximum cost is thus greatly reduced, and as coke and water are the only materials needed, the preparation of hydrogen by this method entails comparatively small expense. Previous to _ the discovery of this method, the lifting power of the hydrogen obtained was 1.981b5. per cubic yard whereas now hydrogen, with a lifting power of 2.0091b5. per cubic yard, can be prepared.— ‘ £ Frankfort Zeitung. ”