Raw biomass does not perform efficiently in its natural form
Raw biomass does not perform efficiently in its natural form (Volesky, 1990) but requires pre-treatment. (Sinha, 2003) reported that activated carbon prepared from water hyacinth gave better fluoride removal efficiency than the non-carbonized plant. Pre-treatment techniques can range from cutting or grinding of dry biomass to acid or base washing (Michalak I. &.-K., 2013). Pre-treatment can also include modification of surface area, pore-size distribution and surface functional groups. The physical pre-treatment methods include heating, boiling, freezing, thawing, drying, lyophilization and autoclaving. Chemical pre-treatment methods on the other hand include washing with various organic and inorganic compounds, such as acids, organic solvents, and alkalis (Gautam, 2014). Alkaline treatments on biomass have been reported to enhance the metal ion adsorption capacity in many cases (Gautam, 2014). Acid treatment of biomass on the other hand almost has no influence on metal biosorption (Wang, 2009). (Babalola, 2008) used 150 size mesh screen B. alba biosorbent that was dried and pulverized. This resulted in 86%, and 59% of Pb and Cd removal respectively.