Adsorption properties of the bamboo-charcoal for chromium(VI)

The adsorption properties of bamboo-charcoal for Cr(Ⅵ) ion in water solution were studied.Effects of some factors,such as particle size and quantity of bamboo charcoal,pH and initial concentration of the solution,absorbing time,temperature,on the removing of Cr(Ⅵ) ion from water solution were investigated.The results show that the adsorption capacity of bamboo-charcoal particles reduces with the increase of their diameter.The adsorption behavior of bamboo-charcoal properly adapts to the changing of the initial concentration of Cr(Ⅵ) ion when Cr(Ⅵ) ion is in acid condition,especially when pH value is less than 3.So that it can keep the absorption for Cr(Ⅵ) ion in a good level and the absorption will bring into equilibrium within 120min.The removal rate can reach to 87.8% or much more if the mass ratio of bamboo-charcoal to Cr(Ⅵ) ion is 1200∶1.The isothermal adsorption behaviors of the bamboo-charcoal for Cr(Ⅵ) ion obey the Freundlich equation.Meanwhile,the adsorption of bamboo-charcoal for Cr(Ⅵ) ion is easier below 20℃,coming with better adsorption effects.So,the bamboo-charcoal is an ideal absorption material for the removing of Cr(Ⅵ) ion.