Removal of bromophenol blue dye from water onto biomass, activated carbon, biochar, polymer, nanoparticle, and composite adsorbents

Bromophenol blue is a toxic triphenylmethane dye that is widely used in various industries. The dye-contaminated wastewater released from the industries results in substantial water pollution, causing several health problems and having severe negative consequences for the ecosystem. As a result, its toxic presence in environmental water is a cause for serious concern. Therefore, the removal of wastewater is vital to preserving environmental quality. The adsorption process stands out among several water treatment techniques due to its low cost, efficiency, simplicity, selectivity, and recyclability. Thus, several adsorbents have been applied for the treatment of bromophenol blue-contaminated water via the adsorption technique. This review presents the adsorption of bromophenol blue onto bio-based adsorbents such as biomass, activated carbon, and biochar as well as other potent materials like nanoparticles, polymers, and composite. The isotherm, kinetics, thermodynamics, and mechanism of the adsorption process were all discussed. We also considered the regeneration of the adsorbents and their reusability in the treatment process. Moreover, research gaps in many aspects were discovered, and future research proposals were offered.