WATER HYACINTH (EICHHORNIA CRASSIPES) AS A PROMISING BIOSORBENT IN REMOVAL OF HEAVY METALS.

Water hyacinth (Eichhorniacrassipes) is a naturally abundant plant having substantial heavy metal adsorptive capacity. E. crassipes is considered to be a noxious weed in many parts of the world due to its proficiency to grow and depletion of nutrients and oxygen from water bodies. Nonetheless, several studies have shown E. crassipesas a candidate for the treatment of wastewater contaminated with heavy metals. The present review aims to compile in a single paper the numerous studies conducted on the use of water hyacinth species for the removal of heavy metals in solution. The methods include a binder material produced either from the roots, shoots, fibers, pellets, the whole biomass, biochar or activated carbon derived from the water hyacinth biomass,and involve a process of binding such as biosorption, pyrolysis, immobilization with micro algae, or modification with nanoparticles. The paper also specifies with each method the extent of removal of metal ions and discusses about a specific disposal method of the metal contaminated biomass. Regardless the ability to act as an invasive aquatic species, E. crassipes has a great potential to be used as an in situ cost effective biosorbentphytotechnology for the amelioration of contaminated wastewaters with heavy metals