In present study aqueous extract of walnut husk was used for the simple, cost-effective synthesis of multiwalled carbon nanotubes (MWCNT) embedded with bimetallic iron-copper (Fe–Cu) nanoparticles, which exhibits adsorption capacity of 769.23 mg/g and 804.50 mg/g for Brilliant Blue (BB) dye and Direct Black (DB-19) dye respectively. The MWCNT@Fe–Cu were characterized by using FTIR, BET, FESEM, EDX, and XRD. The adsorption experiments were conducted by varying concentrations (50 ppm–200 ppm), pH (2.0–11.0), contact time (1 min–5 min), and temperature (30 °C–60 °C) to investigate their effect on adsorption. The adsorption data was best fit with the pseudo-second-order kinetics and Langmuir isotherm model, adsorption process was endothermic and spontaneous. The adsorption of each dye up to the 5th adsorption/desorption cycle was >95 %. From the 6th cycle to the 20th cycle the adsorption decreased from 97 % to 60.98 % and 95 % to56.76 % in the case of BB dye and DB-19 dye respectively. The unique feature of adsorbent is its pH independence as it showed more than 90 % removal efficiency in acidic as well basic medium. All findings underscore the effectiveness of synthesized MWCNT@Fe–Cu to be used as a potential adsorbent for organic dyes removal from industrial effluent.