DeterminationofTotalNitrogeninWasteWaterwithOxidativeCatalyticCombustionandChemiluminesenceDetection

Introduction

Nitrogen is a type of nutrient pollution that comes from the microbial digestion of animal wastes or nitrogenbased fertilizers. High levels of nitrogen in bodies of water can result in harmful algae blooms, which reduces nursery habitats, kills fish and forms oxygen-starved "dead" zones. Drinking water containing high concentration of nitrite (NO₂^-) or nitrate (NO₃^-) can also adversely affect infants and children as it results in methemoglobinemia, a blood disorder that interferes with the body's processes for carrying oxygen to cells and tissues. Hence, it is important to monitor nitrogen level in drinking water and waste water. This application news demonstrates the analysis of total nitrogen (TN) in Certified Reference Materials (CRM) waste water samples using Shimadzu TOC-LCSH coupled with TNM-L TN analyser. The TOC-LCSH and TNM-L measure TN according to BS EN 12260. The nitrogen compounds in water that can be measured comprises of free ammonia, ammonium, nitrite, nitrate and organic compounds. Dissolved or gaseous nitrogen (N₂) cannot be determined using this method. The TN in test solution undergoes oxidative catalytic combustion at 720^oC to nitrogen oxides. After the nitrogen oxides reacts with ozone, the nitrogen dioxides are measured by a chemiluminescence detector.

November 19, 2014 GMT