Ammonia (NH3) is a well-known, widely spread air pollutant, which is present almost everywhere in low ppm/ppb concentrations. So this chemical can be found in various processes, where gases are the basic media, such as steam crackers producing gaseous hydrocarbons for further production steps like polymerization. Gases like this are for example Ethylene, Propylene and even so called cracker gas, which is mostly a mixture of above mentioned gases as well as Water and Hydrogen. The gases of interest are separated and afterwards fed into a pipeline which is serving other chemical plants, producing Polyethylene f.i.


NH3 in processes like this can be a problem in terms of process efficiency, quality control and avoidance of damages, which cause the need to replace very expensive equipment such as catalysts. The fast, accurate and quantitative measurement of NH3 in Hydrocarbon streams is a growing need in plastics manufacturing. A NH3 amount which is higher than 5 ppm can poison catalysts and is influencing the quality of the produced polymers in an unacceptable way.


The IMS-Analyzer is capable of detecting and quantifying NH3 directly from f.i. Ethylene or even in the process step of steam cracking beforehand to avoid technical problems as well as ensuring the quality and efficiency. The outstanding sensitivity and resolution as well as the almost immediate response to concentration changes make the IMS-Analyzer to one of the most suitable process monitoring techniques available. Compared to other methods used in that field like process gas chromatographs, IMS is relatively cheap.

The IMS-Analyzer as IMS and GC-IMS are based on a field proven Ion Mobility Spectrometry (IMS) technique that is highly selective and sensitive to Ammonia. IMS is an atmospheric pressure, time of flight (TOF) detection technique. The sensitivity, selectivity and speed of response make the technique superior in many aspects to other monitoring methods. Unlike electrochemical devices, the IMS units are impervious to extreme temperature or humidity conditions. In addition, in contrast to paper tape detection methods, the IMS units are designed for long term, continuous measurements with little or no maintenance and few consumables. The electronics are completely solid-state without moving parts or optics to require alignment.