Efficiency of Pre-Treated Immobilized Chara Algae (C. vulgaris) for Biosorption of Copper and Lead from Aqueous Solutions

Abstract

The present study evaluates the potential of chemically modified, immobilized Chara algae (C. vulgaris) to remove copper and lead from aqueous solutions. Chara algae were prepared and studied for their ability to remove heavy metal ions prepared solutions. In a batch mode, several factors affecting the adsorption process such pH, temperature, contacting period and algal dose on adsorption efficiency were studied. Results showed that the metal adsorption process takes place quickly at pH values (5.0-6.0), temperature level (25-30) oC and the order of the accumulated metal ions is Cu>pb.The results showed that the handling with low concentration of nitric acid at 0.05 normality was effective in the process of desorbing metal ions. So as for regeneration of algae, 0.2 M sodium hydroxide is very effective. The regenerative algae were used for five cycles of biosorption, without losing its demineralization efficacy. FTIR absorption spectroscopic analyzes showed that all groups that present in the algae are responsible for the main biological absorption of metal ions.Adsorption process specifications are more effective when using modification processes, as the maximum adsorption of algae for both lead and copper was within a range of 6.5-10.3 mg per gram of algae when using the alkaline treatment. While the acid treatment reduced the amount of adsorbent by 4.2-5.8 mg per gram algae; The adsorption process is fast and occurs by 90% within the first 15 min. Heavy metal adsorption was observed at very low levels at pH values as low as 2.0. Algae are effective in removing lead, copper and other light metal ions from wastewater.