Agricultural byproducts like rice husks and peanut shells are widely accessible. Rice Husk Peanut Shell Biochar (RHPSB), a new bio-adsorbent, is used in this study to remove methylene blue dye from the textile industry effluent. This minimizes the environmental impact of waste disposal. The biochar was synthesized through pyrolysis, a relatively low-cost and energy-efficient process in a muffle furnace at 500 °C. A reactor containing an aqueous solution of MB dye (50 ml) was loaded with the desired concentration (0.25, 0.50, 0.75, 1.5, 3.0 gm/50 ml) of RHPSB powder, and adsorption was facilitated. The mixture was incubated at room temperature in an incubator shaker at 120 rpm until equilibrium was reached. The pH level was kept constant at 8.3. The removal efficiencies of MB by RHPSB in a batch experiment were 73.0–98.9% at conditions, pH (6.0–11.0); Biochar dosage (0.5–6.0 g/100 mL) for 5 days. Thus, RHPSB is a more effective adsorbent for dye removal. Isotherm profiling, Adsorption kinetics, and Morphological Analysis by Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were also done to ensure the efficiency of the biochar. The PHz value was 7.8 for the RHPSB. The best adsorption isotherm and kinetics data best matched for Langmuir (R2 0.9981) and pseudo-second-order equation (R2 0.9986). The results of this study demonstrate that RHPSB is a highly effective adsorbent for the removal of methylene blue dye from textile industry effluent, opening up intriguing possibilities for long-term and sustainable wastewater treatment solutions.