Chromium(VI) Heavy Metal Biosorption in Citarum River Water Sample Using Saccharomyces cerevisiae and Rhizopus oryzae Biomass

The Citarum River was regarded as the World’s dirtiest river in 2018, characterized by a Basin situated adjacent to several textile and electroplating industries. Hexavalent chromium metal (Cr 6+ ) is a toxic, carcinogenic heavy metal found in the wastes of these industries. Furthermore, biosorption with biological adsorbents, including Saccharomyces cerevisiae and Rhizopus or y zae , is an alternative method for treating water polluted with heavy metals. This study therefore aims to adsorb Cr 6 + heavy metals from Citarum River water using S. cerevisiae and R. or y zae biomass in two locations: Nanjung and Pangauban, with various biomass concentrations and stirring speeds. For this study, 0.25, 0.5, and 0.75 g of R . or yzae suspension, as well as 250, 500, and 750 µ of S. cerevisiae were used as adsorbent, while rotated at speeds of 250 rpm, 750 rpm and 1500 rpm. Subsequently, the Cr 6 + metal content was measured using a UV-Vis spectrophotometer at a wavelength of 525 nm, and calculated based on a standard curve. The results showed S. cerevisiae and R . or y zae are able to reduce the levels of Cr 6+ in Citarum river water. The most reduction was obtained with the highest concentration of the adsorbents, 750 µ for S. cerevisiae and 0.75 g for R. or y zae , at the speed of 1500 rpm. S. cerevisiae and R . or y zae have great potential as biosorbents for the in situ remediation of Citarum River contaminated with heavy metals.