Production of anhydrous ammonia and aqua ammonia enriched in 15N from (15NH4)2SO4

• Autor(a) principal: Bendassolli, José Albertino
• Data de Publicação: 2002
• Outros Autores: Trivelin, Paulo Cesar Ocheuze, Ignoto, Raquel de Fátima
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Scientia Agrícola (Online)
• Texto Completo: https://www.revistas.usp.br/sa/article/view/21773
• topic: ammonia-15N; nitrogen-15N; stable isotope; amônia-15N; nitrogênio-15; isótopo estável

In Brazil aqua ammonia is an important fertilizer for soil fertilization of the sugarcane crop. The efficiency of the use of nitrogen fertilizers (EUF) by crops is a factor that has influence on agricultural productivity. The isotope technique of 15N labeled fertilizer is used for EUF determinations. In this paper the methods for production, in a same system, of anhydrous ammonia (15NH3) and aqua ammonia (15NH3aq), both enriched in the heavy stable isotope of nitrogen, using ammonium sulfate (AS) labeled with 15N [(15NH4)2SO4 ] as raw material, are presented. The parameters evaluated in the processes were: temperature (60, 70 e 75°C); reaction time (90, 120, 150, 165, 210 e 255 minutes), flow of N2 carrier gas (140, 180 e 220 mL min-1) and mass of AS (40, 72.6, 106, 132 e 200 g). The best conditions related to the production of the 15NH3 e 15NH3aq, were obtained at a temperature of 70°C, flow of N2 carrier gas of 180 mL min-1 and a reaction time of 210 minutes. The N concentration of the 15NH3aq was between 15-20% (w/w), with the 15NH3aq production of 280 mL with concentrations around 15% (w/w) for each batch. The overall yield of the process ranged from 91 to 99% and was directly related to the mass of AS. The unrecovered 15NH3 was very low.