A comprehensive comparative study on methylene blue removal from aqueous solution using biochars produced from rapeseed, whitewood, and seaweed via different thermal conversion technologies

• Production of biochars from three distinct UK-based biomasses via different thermal conversion technologies. Application in methylene blue removal wastewater. Seaweed-based exhibited the greatest potential MB adsorption. Pseudo-second-order kinetic model explains adsorption over seaweed-based biochars. The process was described well by Langmuir isotherms for This paper presents, first time, a comprehensive comparative analysis using distinctly UK-sourced biomass feedstocks, produced processing techniques, to adsorb dye. Biochars were made rapeseed, whitewood, and seaweed ( Laminaria Digitata ), hydrothermal conversion, pyrolysis, torrefaction. Adsorption models developed each biochar at temperatures, pH initial dye concentrations. Relatively high levels capacity achieved (?150 mg/g), with reasonable rapeseed-based (?60 whilst found be relatively low whitewood-based (<30 mg/g). A provided best fit experimental results. isotherm showed better biochars, while Freundlich maximum (Q o ) biochars; ?175 mg/g seaweed-Torrefaction ? 117 seaweed-Pyrolysis. Negative Gibbs free energy (?G°) values observed < seaweed-Pyrolysis 0, which indicates that could thermodynamically favourable due spontaneous nature Our investigation has shown wastewater application as part holistic whole life cycle valorisation pathway. However, it is not suitable all types emphasises need tailoring unique pathways biomasses.