Effect of adsorbent activation conditions from spent coffee ground (SCG) using H2SO4 on Cr (VI) adsorption

The electroplating industry produces chromium Cr (IV) metal waste which causes environmental problems such as poor water quality, damage to aquatic ecosystems, and health impacts on humans. The chromium Cr (IV) levels must be reduced first through the adsorption process before the chromium Cr (IV) metal waste is discharged into the environment. The adsorption process is an environmentally friendly and inexpensive process that researchers demand. Utilization of spent coffee grounds (SCG) as an adsorbent in the adsorption process will utilize coffee grounds biomass waste and produce good absorption efficiency of chromium metal in industrial waste. This study aims to improve the performance of spent coffee grounds adsorbent for the adsorption process of chromium Cr (IV). Spent coffee grounds (SCG) as much as 25 g will be activated first with sulfuric acid activator with an activation time of 1 hour, 2 hours, and 3 hours using a ratio of spent coffee grounds with activator 1:4, 1:5, and 1:6. The best condition for the percentage of spent coffee grounds adsorbent removal was at the activation time of 3 hours with a ratio of 1:6 of 88.50%.