**5. Conclusion**

The adsorption of Ni(II) metal ions from synthetic aqueous solutions is investigated using BGMA as a low-cost adsorbent. At a pH of 6, 2 g of biomass input, and an agitation speed of 120 rpm, the greatest adsorption capacity of BGMA was determined to be 42.056 mg/g. Because the ionic strength decreases with increasing initial Ni(II) metal ion concentration, the percentage elimination decreases and the equilibrium metal absorption (qeq) increases. The equilibrium experimental data suggests that the isotherm has a L shape, indicating that solvent and Ni(II) are competing for the active sites of BGMA. Furthermore, it suggests that the BGMA has a restricted capacity for

*Removal of Divalent Nickel from Aqueous Solution Using Blue Green Marine Algae… DOI: http://dx.doi.org/10.5772/intechopen.103940*

Ni adsorption(II). Furthermore, the efficacy of various isotherms for modelling is investigated using a 1-parameter isotherm, a 13-parameter isotherm, a 16-3-parameter isotherm, a 4-4-parameter isotherm, and a 1-5-parameter isotherm. The experiences are graphically depicted. The Fritz-Schlunder-V isotherm model is obviously relevant in characterising the mechanism of Ni(II) adsorption under the conditions utilised in this work, which was followed by Freundlich. The qmax of 41.89 mg/g for this model reveals its significance even more clearly.
