Search Results for spent-coffee

Abstract

This study focuses on reuse of biowaste material locally available as spend coffee to synthesis high surface area biochar and evaluate its potential to remove dyes with acidic and basic in nature, as Acid Fuchsin and Methylene Blue dyes. The biochar was fabricated using chemical activation with various concentrating (20, 30, 50) vol. % of phosphoric acid (H3PO4). The pyrolysis process carried out in a tubular furnace under flow of nitrogen (N2) at 600°C for 3 hours. The final prepped biochar was analyzed using various techniques such as XRD, SEM, FTIR, TGA, EDX, N2-adsorption, BET, and pore volume (Vpore). Furthermore, batch adsorption experiments were conducted to remove Acid Fuchsin and Methylene Blue dyes from aqueous solutions under different variables of pH of solution (2-8), contact time (0-240) min, initial dye concentration (20-200) ppm, and weight of dosage (0.1-0.5) g/L. The results show that the best surface area and pore volume has been archived for the prepared biochar at 30% H3PO4 concentration were (1385.269 m2/g and 1.12 cm3/g) respectively. As well as, the maximum removal percentage was 92.5% for Fuchsin dye and 90% for Methylene Blue dye achieved at 180 minutes of adsorbing time, with maximum removal achieved with initial dye concentration of 20 ppm, 6.5 pH solution, and 0.3 g/L adsorbent. The study found that Freundlich isotherm and kinetic adsorption models fit well with the batch experimental data, which indicates homogenous distribution and limiting active sites with adsorption capacity (384.61) mg/g and (357.14) mg/g for Acid Fuchsin and Methylene Blue dyes, respectively. While, the pseudo-second-order kinetic model indicates a physic-sorption is the limiting step.