Abstract International Seminar-2008:

Biosorption of heavy metal ions by Spirogyra subsalsa biomass: effect of immobilized biomass within sodium silikat Mawardi 1), Edison Munaf 2), Soleh Kosela 3) , Widayanti Wibowo3) 1) Laboratory of Analytical Chemistry, Faculty of Mathematics and Science, State University Padang, Padang 25131, Indonesia 2) Laboratory of Analytical Environmental Chemistry, Faculty of Mathematics and Science, Andalas University, Padang 25163, Indonesia 3) Laboratory of Chemistry, Faculty of Mathematics and Science, Indonesia University, Depok 16424, Indonesia

Abstract In this research were learned about biosorption heavy metal cations, by green algae S. subsalsa biomass were immobilized within polysilicate matrix (sodium silicate) was examined in a continuous packed-bed column. The effects of operating parameters, such as flow rate, influent pH and infuent metals concentration were investigated. Significanly, the immobilized biomass showed IR spectrum not deference with free elgae biomass. The biosrption process were a rapid process, wherein more than 50% of the final uptake value occur at rate flow 1.5 mL/minute. The biosorption capacities of biomass for cations increase rapidly with pH between pH 2,0-3,0 then the maximum sorption was seen at pH 4,0. The biosorptive capacity increased with initial concentartion in the range 50—200 mg/L. A comparison of the biosorption of each Pb2+, Cu2+, Cd2+ and Zn2+ cations by immobilized and free algae biomass showed an increase in uptake of over 4,25; 15,95; 8,84 and 3,49%. respectively. The immobilized biomass could be regenerated using nitrate acid, HNO3, and significantly proportional with used nitrate acid concentration, with up to 89 % Pb2+ recovery by 0,5 M HNO3, while Cu2+ at 0,05 M HNO3 have desorbed about 60% and Cd2+ and Zn2+ cations recovery more than 80% by HNO3 0,5 M. This study suggeststhat such an immobilized biosorbent system has the potential to be used in the industrial removal and recovery of Pb2+, Cu2+, Cd2+ and Zn2+ cations from aqueous solution. . Keyword : S. subsalsa, biosorption, desorption, sodium silicate, nitrate acid Corresponding Author: E-Mail: [email protected]