Evaluating coffee husk biochar as a sustainable and novel adsorbent for lead and copper in wastewater
摘要
The physicochemical characteristics of the coffee husk (CFH) biochar and its adsorption capacities for lead and copper ions were examined in this study. With a CFH biochar dosage of 2.0 g/L and heavy metals concentration of 5.0 mg/L, the adsorption process reached equilibrium approximately 180 min. The adsorption isotherms were explained by the Langmuir, Freundlich, and Temkin models. More precisely, the Langmuir model was most appropriate for the monometallic system, while the Freundlich model was most appropriate for the simultaneous two-metal system. With the maximum adsorption capacity (Qmax) determined by the Langmuir model to be 10.02 mg/g for lead and 13.08 mg/g for copper in the monometallic system, the CFH biochar demonstrated significant adsorption capacities for these two metals. Adsorption isotherms indicated competitive adsorption between the two metals in the mixed-metal system, with the CFH biochar showing preferential adsorption for lead over copper ions. The pseudo-second-order kinetic model accurately represented the adsorption kinetics of two metals onto the CFH biochar. The environmental sustainability issues surrounding the use of CFH biochar in wastewater treatment could be resolved with more investigation into the life-cycle assessment and its uses. Even though some biochar is inexpensive and biodegradable, incorrect handling and disposal of remaining biochar that is contaminated with pollutants harm water bodies, necessitating further cooperative research into sustainable management and disposal of biochar. Overall, the use of CFH biochar as a heavy metal adsorbent lowers the expenses associated with treating agriculture wastes and produces reasonably priced materials that effectively and ecologically friendly adsorb water pollutants.