Sequential Injection Analysis for Determination of Ammonia in Livestock Wastewater Using Acetoacetanilide as Hantzsch Reaction Reagent

Abstract

Ammonia is a dangerous chemical compound in high concentrations. About 80-90% of ammonia total emissions come from animal fertilizer that produced from livestock, such as cattle farming. Based on the Minister of Environment Regulation Number 5 of 2014, the ammonia level in waste water standards for livestock activities is 25 mg/L. Some of the most common methods that used for determining ammonia are selective spectrophotometry and selective electrode, but the method has a disadvantage such as time consuming and low sensitivity. To overcome this problem, the aim of this study was to determine the dissolved ammonia levels in the liquid waste stream of cattle farms using the Sequential Injection Analysis (SIA) method by UV-Vis spectrophotometry at a wavelength of 307 nm based on the Hantzsch reaction using acetoacetanilide and formaldehyde reagents in acetate solution to form Dihydropyridine derivatives. The optimum condition of product formation occured in the order of reagents and sample segmentation of formaldehyde (R)-ammonia (S)-AAA(R) acetate with the volume ratio 75μL: 50μL: 100μL, respectively. The optimum conditions of the proposed method are 0.06 M of AAA concentration, 15% of formaldehyde concentration, reaction time of 40 s, and flow rate of 175 μL. High sensitivity (LOD:0.122 mg/L), fast analysis (175 s/sample) and high accuracy (recovery test > 94%), less and harmless waste could be attributed as advantages of the proposed SIA method.