Innovation in Acid Mine Drainage Remediation Using Coffee Waste Biochar in Michiquillay, 2025

Abstract

This research aims to remove heavy metals from Acid Mine Drainage (AMD) using activated carbon from coffee waste. To do this, 0.5 g, 1 g, and 1.5 g of biochar were applied in triplicate in 250 mL beakers each; the tests were conducted at 15-minute intervals for a total time of one hour. The results showed the initial presence of copper (3.9185 mg/L), zinc (18.2 mg/L), and iron (0.215 mg/L); after the treatment process, the final concentrations were 0.0155 mg/L, 1.49833 mg/L, and 0.0309 mg/L, respectively. Additionally, an increase in the average pH was recorded from 4.77 to 7.67, achieving a neutral pH. These results demonstrate that coffee biochar, due to its high porosity when activated, has a remarkable absorption capacity. Ultimately, 99% copper, 85% zinc, and 91% iron were removed, confirming the high efficiency of this activated agroindustrial waste and meeting Environmental Quality Standards.