| 摘要 |
<p>PURPOSE:To continuously, safely and conveniently treat a nitrogen fluoride- contg. waste gas for a long time without by-producing a highly toxic gas such as oxygen difluoride by bringing the gas into contact with boron nitride at a specified temp. CONSTITUTION:The waste gas contg. the nitrogen fluoride of the used nitrogen trifluoride necessary for the production of a VLSI, etc., is brought into contact with boron nitride at 100-600 deg.C or preferably at 200-400 deg.C. The waste gas is then brought into contact with water, an aq. alkaline soln. and an aq. mineral acid soln. to remove the contained nitrogen fluoride. The nitrogen fluoride in the waste gas is rendered harmless extremely efficiently and economically in this way.</p> |
