Design of regenerable brewer's spent grain biochar-embedded xanthan gum/alginate double-network hybrid gel and biosorptive decolorization.

Access to safe and clean water has become a global challenge due to the growing pollution caused by toxic and non-biodegradable synthetic dyes. Treatment systems based on the use of affordable, readily produced, and effective materials are of critical importance. An eco-friendly treatment approach was developed by integrating brewer's spent grain biochar (BSGBio), xanthan gum (XG), and alginate (Alg) into a novel biocomposite sorbent (BSGBio@XG-Alg) for the efficient removal of Basic Blue 12 (BB12) from aqueous solutions and real wastewater. The biosorption performance of BSGBio@XG-Alg was investigated under both batch and dynamic flow systems. The effects of critical parameters, including solution pH, biosorbent amount, contact time, initial dye concentration, and flow rate, were investigated. Under optimized batch and column conditions, the suggested biocomposite achieved decolorization efficiency of nearly 100%. The maximum biosorption capacity was determined to be 310.73 mg g-1. Kinetic and equilibrium studies indicated that the biosorption process was well described by the pseudo-second-order kinetic model and the Langmuir isotherm model. The properties of the biosorbent were investigated using FTIR, SEM, and EDX analyses. The results confirmed effective interactions between BB12 molecules and the biocomposite. The regeneration tests demonstrated that BSGBio@XG-Alg exhibited high stability and reusability during repeated usage cycles. BSGBio@XG-Alg achieved a treatment efficiency of 94.38% when tested on a wastewater sample. Because of its remarkable biosorption effectiveness, stability, reusability, and environmental friendliness, BSGBio@XG-Alg is a highly promising option for treating dye-contaminated waters.