Cationic dialdehyde cellulose microfibers for efficient removal of eriochrome black T from aqueous solution

[Display omitted] •An agroindustrial residue transformed into a new type of biosorbent.•From sugarcane bagasse to cationic dialdehyde cellulose (cDAC) by a simple method.•Efficient removal of emerging contaminant from water.•The interaction mechanism is explained by the non-linear Langmuir isotherm model.•Recyclable biosorbent, which can be applied efficiently 4 times. Materials based on cellulose have been widely used as a decontaminant agent of wastewater. However, it can not be found in the literature any application of the cationic dialdehyde cellulose (cDAC) in anionic dye removal. Therefore, this study aims a circular economy concept using sugarcane bagasse to obtain a functionalized cellulose by oxidation and cationization. cDAC was characterized by SEM, FT-IR, oxidation degree, and DSC. Adsorption capacity was evaluated by pH, kinetic, concentration effect, strength ionic tests, and recycling. The kinetic followed Elovich model (R2 = 0.92605 for EBT = 100 mg/L) and non-linear Langmuir model (R2 = 0.94542), which resulted in a maximum adsorption capacity of 563.30 mg/g. The cellulose adsorbent reached an efficient recyclability of 4 cycles. Thus, this work presents a potential material to become a new, clean, low-cost, recyclable, and environmentally friendly alternative for effluent decontamination-containing dyes.