A cost effective and sensitive method for the determination of ammonia concentration in nanocrystal mordenite

Document Type: Reasearch Paper


1 Department of Chemistry, Faculty of science, Islamic Azad University, Rasht Branch, Rasht, Iran.

2 Department of Chemistry, Faculty of Science, University of Mohaghegh Ardabili, Ardabil, Iran.



The reduction capacity of ammonia while present even at ppm level can be demonstrated by the increased encounter probability between ammonia and methylene blue dye (MB+) incorporated in nanomordenite and Na-MOR zeolites. The rate of reduction methylene blue dye by ammonia on the surface nanomordenite zeolite is faster than Na-mordenite (Na-MOR) zeolite.Because nanomordenite zeolite with high silica (Si/Al=15) and surface area 400 (m2/g) is referred to as hydrophobic support with respect to Na-MOR zeolite (Si/Al=6.5). On the other hand, the rate of color bleaching of MB+ by ammonia was found to be fastest in proton form of nanomordenite and mordenite zeolites. The results obtained with the zeolites were also compared with non-ionic micelle (TX-100). The calibration graph is valid for wide range of concentrations in nanomordenite zeolite. The limit of detection (LOD) is 0.12 mg ml-1. This method is simple, sensitive and easy to carry out. By using only a UV-visible spectroscopy, ammonia can be quantified.