Production of Colourless Glass in Tank Furnaces with Reference to use of Selenium

JSGT 1922 V06 T168-T181

The production of colourless glass in tank furnaces several years ago in America passed out of the experimental into the commercial stage. In this country colourless glass had only been made up to three or four years ago in pot furnaces. There has, however, been a rapid development in the use and manufacture of colourless glass containers and the demands of the public have already led, and will lead in the future, to the conversion of former green glass tank furnaces into those producing colourless glass. The success of the process has been made possible through the introduction of selenium, either in the form of elementary selenium, or as a salt such as sodium selenate or selenite. Selenium differs in its action from manganese dioxide in several ways, more particularly, however, for the reason that it functions in the presence of reducing agents, whereas manganese dioxide requires just the opposite conditions. The atmosphere of a tank furnace is, therefore, not normally very suitable for manganese dioxide, although to a limited extent it is applied. For selenium, however, tank furnace conditions are appropriate.

A. Cousen & W. E. S. Turner