摘要
With the application of chromium increasing, wastewater shows an increase of chromium pollution. In particular, Cr(Ⅵ) has become a major concern because of its high toxicity. Cr(Ⅵ) is recognized to be much more toxic than Cr(Ⅲ). Sugarcane residue is a byproduct of the sugar industry, and it is an important renewable biomass resource. In this paper, sugarcane residues were used to remove chromium ions from wastewater in order to develop cheap and efficient heavy metal adsorption materials. The effects of pH, sugarcane residue dosage, sugarcane residue particle size and chromium ion initial concentration on chromium ion removal and the kinetics of chromium ion removal at normal temperature were investigated. The results showed that the removal rate of Cr(Ⅵ) and Cr(Ⅲ) increased with an increase of sugarcane residue concentration, and decreased with an increase of particle size and the initial concentration of chromium. The removal effect of Cr(Ⅲ) increased with increasing pH, and the removal effect of Cr(Ⅵ) decreased with increasing pH. The removal kinetics of chromium fitted well with a pseudo-second-order-model. Sugarcane residues had a higher adsorption capacity for Cr(Ⅲ) than for Cr(Ⅵ). This paper provides a basis for the treatment of chromium containing wastewater or other heavy metal wastewater in the future.
With the application of chromium increasing, wastewater shows an increase of chromium pollution. In particular, Cr(Ⅵ) has become a major concern because of its high toxicity. Cr(Ⅵ) is recognized to be much more toxic than Cr(Ⅲ). Sugarcane residue is a byproduct of the sugar industry, and it is an important renewable biomass resource. In this paper, sugarcane residues were used to remove chromium ions from wastewater in order to develop cheap and efficient heavy metal adsorption materials. The effects of pH, sugarcane residue dosage, sugarcane residue particle size and chromium ion initial concentration on chromium ion removal and the kinetics of chromium ion removal at normal temperature were investigated. The results showed that the removal rate of Cr(Ⅵ) and Cr(Ⅲ) increased with an increase of sugarcane residue concentration, and decreased with an increase of particle size and the initial concentration of chromium. The removal effect of Cr(Ⅲ) increased with increasing pH, and the removal effect of Cr(Ⅵ) decreased with increasing pH. The removal kinetics of chromium fitted well with a pseudo-second-order-model. Sugarcane residues had a higher adsorption capacity for Cr(Ⅲ) than for Cr(Ⅵ). This paper provides a basis for the treatment of chromium containing wastewater or other heavy metal wastewater in the future.