<p>In India large quantity of Jujube (Ber) fruits is produced but the kernels of this fruit are typically discarded in open areas. This investigation aims to pyrolyze these waste kernels for the preparation of non-activated and KOH-activated biochar and utilise the resultant biochar as adsorbent for the removal of Amido Black 10B (AB-10B) and Eosin Blue (EB) dye from binary synthetic solutions. Simultaneously comparative analysis of dye adsorption efficiency between the non-activated and activated Ber biochar were also performed. Both dyes belongs to the mutagenic and carcinogenic acid dye group, causing threats to aquatic life, plants, and human health. The batch adsorption experiments were performed using the operating parameters like dye concentrations, adsorbent dosage, pH, temperature, and contact time to optimize the removal efficiency. The non-activated and activated Ber kernel biochar were underwent various characterizations using techniques such as Thermal Gravimetric Analysis (TGA), Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDS), zeta-potential, Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction (XRD) for both before and after adsorption. The behavior and mechanism of the process was assessed through kinetics models, isotherms, and thermodynamics. The KOH-activated biochar derived from Ber kernels has highly porous structure and different functional groups which enhances its capacity to adsorb dyes. It offered superior adsorptive capability for the elimination of AB-10B dye (98%) and EB dye (89%) from binary dye solution in comparision to non-activated biochar (AB-10B = 40% and EB = 36%). Hence, this biochar can be an eco-friendly, affordable, and sustainable alternative adsorbent for the treatment of industrial wastewater.</p> Graphical abstract <p></p>