Teledyne T201 Manuel D’Utilisation

T201 Ammonia Analyzer 

Analyzer Operator Manual 

10 

07271B DCN6646 

  

The Teledyne-API Model T201 analyzer measures ammonia by oxidizing

 

it to nitric oxide by the following reaction: 

4NH

3

 + 5O

2

   

  4NO + 6H

2

O 

The resulting nitric oxide is then measured by the chemiluminescent 
reaction with ozone.  Consult Section 10.1 in the T200 manual (provided 
with this instrument) for more details on the nitric oxide measurement. 

The analyzer uses two converters to oxidize the different sample gases.  A 
high temperature catalytic converter, the M501 NH

3

, converts NH

3

 and 

NOx into NO creating the TN

x

 channel. A second converter, housed inside 

the T201 analyzer and consisting of heated molybdenum, converts all of 
the NO

x

 in the sample to NO producing the NO

x

 channel. The nitric oxide 

channel is measured while bypassing both the M501 NH

3

 and 

molybdenum converter. A Nafion® drier operated in reflux mode, is 
installed prior to the molybdenum converter and the AutoZero valve. The 
drier removes ammonia and water from the switched stream. The 
ammonia would have otherwise been converted by the molybdenum and 
registered as NO

x

. This location provides the drier with continuous flow, 

thereby allowing it to stabilize faster.  

The calculated gas concentrations, ammonia and nitrogen dioxide, are 
computed from the differences between the measured channels, as 
outlined in the following equations: 

NO (Nitric Oxide) Concentration = Measured 

 (Total Nitrogen) Concentration = Measured (NH

3

 + NO

2

 + NO) 

 (Total Nitrogen – Ammonia) Concentration =  

Measured 

(NO

2

 + NO) 

 (Ammonia) Concentration = Calculated as follows: 

[(TNx - NOx) / (NH

3

_CE_FACTOR1)] 

 (Nitrogen Dioxide) Concentration = Calculated as follows: 

[(NOx – NO) / (NO

2

_CE_FACTOR1)]