公开(公告)号：EP1106990A2

公开(公告)日：2001-06-13

申请号：EP00126959.6

申请日：2000-12-08

Applicant: Showa Denko Kabushiki Kaisha

Inventor： Itou, Taizou, c/o Kawasaki Plant ,  Hayashida, Hideki, c/o Kawasaki Plant ,  Kosuge, Yasuhiro, c/o Kawasaki Plant ,  Ishigaki, Fumiyasu, c/o Kawasaki Plant

IPC: G01N21/35

CPC classification number: G01N21/3554 ,  C01B21/06 ,  C01B21/0632 ,  C01C1/003 ,  C01C1/024 ,  C01P2006/82 ,  C23C16/301 ,  C23C16/4402 ,  G01N21/031 ,  G01N21/3504 ,  G01N2021/354

Abstract: Method and apparatus for measuring a water concentration in ammonia, comprising using ammonia having a water concentration of 10 ppm or less as a reference gas, introducing the ammonia at a constant flow rate into a multi-reflection long optical path gas cell, and measuring infrared absorption intensity of water at at least one measurement wave number in the range of from 3,500 to 4,000 cm -1 , from 2,600 to 3,100 cm -1 , or from 1,900 to 2,400 cm -1 at which infrared absorptions of ammonia and water do not overlap.
According to the present invention, analysis of water in a low concentration range of 10 ppm or less in ammonia gas and liquefied ammonia can be performed in a simple and convenient manner.