Adsorption of Cr (Ⅲ) by Sodium Alginate in Aqueous Solution

摘要

The present study was undertaken to develop a cheap effective adsorbent and adsorption process involved in the adsorption of heavy mental-contaminated industrial wastewater using the developed adsorbent. Sodium alginate is the excellent adsorbent for the adsorption efficiency of the chromium (Ⅲ). Operational parameters such as pH, agitation time and adsorbent dosage, initial ion concentration and temperature were also studied. The optimal pH value for Cr3+ adsorption was 6.0. The maximum adsorption capacity of sodium alginate for Cr3+ was 3.12 mmol/g. Adsorption data fitted well with the Langmuir and Freundlich models. However, Langmuir isotherm displayed a better fitting model than Freundlich isotherm because of the higher correlation coefficient than the former exhibited. Desorption studies were carried out with HCl, HNO3, EDTA, Sodium carbonate and deionization water, and quantitative recovery of the metal was evident. The result shows sodium alginate is the excellent adsorbent for Cr3+.