Removal of Formaldehyde by the Cost-Effective Untreated Biosorbent of Chlorella Vulgaris Microalgae

Chlorella vulgaris green microalgae live cells show great potential for removal of pollutant. In this study, the potential of the Chlorella vulgaris microalga as an inexpensive biosorbent was investigated for the removal of formaldehyde (FA). The experimental conditions including pH, contact time, and temperature on the removal of FA were considered and optimized. The sorption thermodynamics and kinetics of FA on biosorbent were studied using linear and nonlinear regressions. Chlorella vulgaris as biosorbent was able to remove 98% of FA within 22 minutes at the pH of 6.0. The sorption isotherm fitted well to the Langmuir isotherm and the sorption kinetics followed the pseudo-second-order model. Based on the Langmuir model, the maximum capacity of the monolayer sorption of Chlorella vulgaris for FA was found to be 180 mg g-1. The rapid and relatively high capacity of natural and untreated Chlorella vulgaris is the main advantage of this biosorbent for wastewater treatment.