The economical production of functionalized Ashe juniper derived-biochar with high hazardous dye removal efficiency

High adsorption capacity is crucial for the commercial application of biochar in contaminant removal. Here, we produced a functionalized biochar with high adsorption capacity for high concentration dye chemicals higher than 300 mg/L in which sulfuric acid treatment was implicated for functionalization. This study presents the effects of the concentration of sulfuric acids (50, 70, and 90%) on the physical and chemical properties of the biochar produced by conventional pyrolysis from Ashe juniper. We found that the high concentration of sulfuric acid was crucial for developing biochar with a high degree of sulfonation and oxidation on the biochar surface and highly developed porosity, resulting in approximately 200 times improved adsorption capacity compared to raw biochar. The implications of the design of experiment (DOE) confirm the significant effects of dosage which also have quadratic effect and initial dye concentration on the adsorption capacity. An adsorption isotherm study revealed that the methylene blue adsorption followed Langmuir isotherm, meaning that the homogeneous surface of the functionalized biochar. By multicomponent adsorption experiment, the functionalized biochar showed a higher affinity to methylene blue than methyl orange, indicating the potential of our products as a promising separator of methylene blue. Furthermore, techno-economic analysis revealed the economic feasibility of functionalized biochar for a dye chemical removal from aqueous solution.