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

Document Type: Reasearch Paper

Authors

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.

10.7508/ijnd.2010.02.007

Abstract

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.

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