Biosorption of chromium(III) by Sargassum sp. biomass
Electronic Journal of Biotechnology
Chromium is present in different types of industrial effluents, being responsible for environmental pollution. Traditionally, the chromium removal is made by chemical precipitation. However, this method is not completely feasible to reduce the chromium concentration to levels as low as required by environmental legislation. Biosorption is a process in which solids of natural origin are employed for binding heavy metals. It is a promising alternative method to treat industrial effluents, mainly
... effluents, mainly because of its low cost and high metal binding capacity. In this work the chromium biosorption process by Sargassum sp. seaweed biomass is studied. Sargassum sp. seaweed, which is abundant in the Brazilian coast, has been utilized with and without milling. The work considered the determination of chromium-biomass equilibrium data in batch system. These studies were carried out in order to determine some operational parameters of chromium sorption such as the time required for the metal-biosorbent equilibrium, the effects of biomass size, pH and temperature. The results showed that pH has an important effect on chromium biosorption capacity. The biosorbent size did not affect chromium *Corresponding author biosorption rate and capacity. Mining activities, agricultural run off, industrial and domestic effluents are mainly responsible for the increase of the metallic species released into the environment. Contrary to toxic organics, that in many cases can be degraded, the metallic species that are released into the environment tend to persist indefinitely, accumulating in living tissues throughout the food chain. A complete understanding about noxious effects caused by the release of toxic metals into the environment and the emergence of more severe environmental protection laws, have encouraged studies about removal/recovery of heavy metals from aqueous solutions using biosorption. Conventional methods as precipitation, oxidation/reduction, ion exchange, filtration, membranes and evaporation are extremely expensive or inefficient for metal removal from diluted solutions containing from 1 to 100 mg/L of dissolved metal. In this context, the biosorption process has been recently evaluated (Volesky, 1990) .