The physiochemical properties of Natural Bentonite Clay (NBC) were modified in this work to increase its adsorption performance. The NBC was mined from Fika town in Yobe State and thereafter subjected to beneficiation to obtain various particle sizes. The modified NBC and Activated Bentonite Clay (ABC) were characterized using X-ray fluorescence to determine the elemental assay of the samples, Fourier transform infrared (FTIR) spectroscopy for the determination of the effect of acid attack and the adsorbate Braunner-Emmet-Teller (BET) method for surface area determination was conducted on the clay sample before and after modification procedure. The surface areas of the adsorbents before and after modification were found to be 160.40 m2/g and 126.50 m2/g for ABC and NBC respectively. The raw and the modified samples had an adsorption capacity of 12.55 and 74.98 mg/g which were used to purify the simulated textile wastewater to investigate their adsorptive performance. The equilibrium data were fitted in Langmuir, Freundlich and Temkin adsorption isotherm models with the aid of origin 9 software using two statistical parameters- the correlation coefficient R and Sum of Square Errors SSE. Results showed the experimental data was best fitted in the Langmuir isotherm model where R values of ABC was consistently higher for dye 1-dye 4 than that of NBC. The SSE of ABC was also found to be consistently lower for all dye adsorption than that of corresponding ABC.