Simultaneous Removal of Toxic Ammonia (NH3/NH4+) from Aqueous Solutions Using New Geomaterial Adsorbent: Application to Aquaculture Effluents

This study evaluates the performance of a new geomaterial (GEOM) based on sodium montmorillonite clay (Na-Mt), local activated carbon (CAC) and fine powder local cement (Chlef plant western Algeria) to remove ammonia from fish farming in a recirculating aquaculture system. The aqueous ammonium (NH4+/NH3) adsorption efficiency of GEOM was compared with its two principals' constituents (Na-Mt and CAC) and another commercial activated carbon (CAG). The results of X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy were used to assess the chemical and physicochemical properties of studied adsorbents. The maximum adsorption capacity of NH4+ on GEOM of about 15.57 mg. g-1 seems to be similar to that of Na-Mt 16.82 mg. g(-1). The study of solution pH showed that the best NH4+/NH3 removal efficiency was at pH=6 for both GEOM and Na-Mt. The efficiency of GEOM for ammoniacal nitrogen (NH4+/NH3) removal was 79.3% in ultrapure water, 94.05% in seawater and 97.5% in real aquaculture wastewater. Thus, the proposed material, GEOM, can be used as a filter material in a bio-filtration process to treat aquaculture wastewater in a real-world context.