Hydrochloric acid concentration and time to maximize lead and cadmium removal in laboratory wastewater

Abstract

The bioadsorption treatment was performed on the wastewater from a university chemical analysis laboratory using Chondracanthus chamissoi algae, commonly known as "mococho," as the biomass. The study factors included the concentration of hydrochloric acid ranging from 1 to 2 N and contact times ranging from 2 to 7 hours in a continuous flow bioreactor. The objective was to determine the combination of factors that maximizes the removal of Lead (Pb) and Cadmium (Cd). A 2k factorial design with central points and the response surface method were used. From the results, it was found that the combination of factors, hydrochloric acid concentration (HCl), and contact time that maximizes the removal of Pb ions is 2.5 N and 6.8 hours, while the combination of factors that maximizes the removal of Cd ions is 2.1 N and 22 hours. It was determined that the study factors generate statistically significant differences in the removal of Pb compared to Cd.