The effectiveness of activated carbon from nutmeg shell in reducing ammonia (NH3) levels in fish pond water

Abstract

Ammonia (NH₃) is one of the compounds found in water, and when it exceeds the threshold, it can become toxic, posing a problem for fish farmers. This research aims to reduce the ammonia (NH₃) levels using activated carbon adsorbents based on nutmeg shell. The activated carbon was produced using a 1 M HCl solution as an activator with temperature variations of 600 °C, 650 °C, and 700 °C. The activated carbon obtained complies with the SNI No.06–3730–1995 standard, with characteristics of 9.23 % moisture content, 8.45 % volatile matter content, 9.71 % ash content, and 81.84 % bound carbon content. The best sample was obtained with an adsorbent mass of 6 g at 700 °C, reducing Ammonia (NH₃) by 90 % with an adsorption capacity of 0.03 mg/g. Subsequently, the sample was subjected to Fourier Transform Infrared (FTIR), X-ray diffraction (XRD), and Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX) analysis. Functional carbon groups were identified, especially at wavenumbers 3745.22 cm⁻¹ and 3621.27 cm⁻¹, facilitating adsorption. The sample had an amorphous structure but contained crystalline carbon structures. The highest peak observed was at 29.57° with a miller index (201). The surface of the sample exhibited pores, predominantly composed of carbon and oxygen. The adsorption mechanism of ammonia (NH₃) on activated carbon occurs through intermolecular interactions. This research demonstrates the potential of a newly developed material for reducing NH₃.